FM 6310, 6320 Combustible Gas Detectors

Approval Standard forCombustible Gas Detectors Class Number 6310, 6320 January 2001 Based in part on ANSI/ISA-12.13.01-2000, Performance Requirements for Combustible Gas Detectors. ©2002 FM Approvals LLC. Portions© ISA. All rights reserved. Foreword FM Approvals are intended to verify that the products and services described will meet stated conditions of performance, safety and quality useful to the ends of property conservation. The purpose of FM Approval Standards is to present the criteria for FM Approval of various types of products and services, as guidance for FM Approvals personnel, manufacturers, users and authorities having jurisdiction. Products submitted for Approval shall demonstrate that they meet the intent of the Approval Standard, and that quality control in manufacturing and/or applications shall ensure a consistently uniform and reliable product or service. FM Approval Standards strive to be performance-oriented and to facilitate technological development. For examining equipment, materials and services, FM Approval Standards: a) must be useful to the ends of property conservation by preventing, limiting or not causing damage under the conditions stated by the Approval listing; and b) must be readily identifiable. Continuance of Approval and Listing depends on compliance with the Approval agreement, satisfactory performance in the field, on successful re-examinations of equipment, materials, and services as appropriate, and on periodic follow-up audits of the manufacturing facility or service/application. FM Approvals LLC reserves the right in its sole judgement to change or revise its standards, criteria, methods, or procedures. TABLE OF CONTENTS 1. INTRODUCTION ..................................................................................................................................................................... 1 1.1 Purpose .............................................................................................................................................................................. 1 1.2 Scope ................................................................................................................................................................................. 1 1.3 Basis for Requirements ..................................................................................................................................................... 2 1.4 Basis for FM Approval ..................................................................................................................................................... 2 1.5 Basis for Continued Approval .......................................................................................................................................... 3 1.6 Effective Date .................................................................................................................................................................... 3 1.7 System of Units .................................................................................................................................................................. 3 1.8 Applicable Standards ......................................................................................................................................................... 3 1.9 Definitions ......................................................................................................................................................................... 3 2. GENERAL REQUIREMENTS ............................................................................................................................................... 6 2.1 Review of Documentation ................................................................................................................................................ 6 2.2 Markings ............................................................................................................................................................................ 6 2.3 Manufacturer’s Installation and Operation Manuals ........................................................................................................ 7 2.4 Construction and Functions ............................................................................................................................................ 10 2.5 Test Equipment Calibration ............................................................................................................................................ 12 3. PERFORMANCE REQUIREMENTS ................................................................................................................................. 12 3.1 General ............................................................................................................................................................................. 12 3.2 Samples and Sequence .................................................................................................................................................... 13 3.3 Preparation of instrument ................................................................................................................................................ 13 3.4 Conditions for test and test area ..................................................................................................................................... 13 3.5 Selectable gas/range instruments .................................................................................................................................... 15 3.6 Un-powered preconditioning storage .............................................................................................................................. 15 3.7 Drop test .......................................................................................................................................................................... 16 3.8 Vibration .......................................................................................................................................................................... 16 3.9 Calibration ....................................................................................................................................................................... 16 3.10 Accuracy ........................................................................................................................................................................ 17 3.11 Temperature ................................................................................................................................................................... 17 3.12 Step change response .................................................................................................................................................... 18 3.13 Humidity variation ........................................................................................................................................................ 18 3.14 Air velocity variation .................................................................................................................................................... 19 3.15 Supply voltage variation ............................................................................................................................................... 19 3.16 Electromagnetic Interference (EMI) ............................................................................................................................. 20 3.17 Long-term stability ........................................................................................................................................................ 20 3.18 Flooding with undiluted gas ......................................................................................................................................... 22 3.19 Additional Tests ............................................................................................................................................................. 22 4. OPERATIONS REQUIREMENTS ....................................................................................................................................... 23 4.1 Demonstrated Quality Control Program ......................................................................................................................... 23 4.2 Facilities and Procedures Audit (F&PA) ........................................................................................................................ 23 APPENDIX A: GENERAL INFORMATION .......................................................................................................................... 24 A-1 Approval Application Requirements ............................................................................................................................. 24 A-2 Requirements for Samples for Examination ................................................................................................................. 25 APPENDIX B: UNITS OF MEASUREMENT ......................................................................................................................... 26 . January 2001 6310. This does not preclude instruments intended for higher concentration ranges.1 This standard is concerned with the details of construction. and flammable gases or vapor concentrations in air. or stationary-type instruments supplied by battery of a non-rechargeable (primary) type or a rechargeable (secondary) type. AND REGULAR MAINTENANCE. 1. marking requirements. INTRODUCTION 1. this standard applies only to systems which utilize defined associated intrinsically safe apparatus (protective barrier assemblies). USE. 1.1. mobile and stationary electrical instruments that sense the presence of combustible gas or vapor concentrations in air. audit of quality assurance procedures.2. or instruments used for residential purposes. Based on associated requirements specified in Section 3. THEY DO NOT NECESSARILY WARN OF TOXIC GAS RELEASES.6 This standard is written for gas detection instruments that are intended to detect gas concentrations in air in the range from zero up to the lower flammable limit (LFL). 1. the purpose of which is to give warning of potential hazard. this standard applies only to the portion of the instrument sensing the flammable gases or vapor concentrations in air. and to portable.1 Purpose 1. performance and testing of portable. this standard considers the suitability of the instruments or parts thereof for use in Class I.7 For instruments used for sensing the presence of oxygen. IT IS ALSO STRESSED THAT FINAL AND LONG-TERM EFFECTIVENESS OF ANY COMBUSTIBLE GAS DETECTION EQUIPMENT DEPENDS HEAVILY UPON THE USER.2 FM Approval criteria may include.5 This standard does not address gas detection instruments of the laboratory or scientific type used for analysis or measurement. WHO MUST BE RESPONSIBLE FOR ITS PROPER APPLICATION.4 This standard addresses combustible gas detection instruments intended to provide an indication or alarm.1 This standard provides minimum requirements for combustible gas detection instruments for FM Approval.2 This standard applies to line-voltage operated instruments rated at 250V nominal or less. open path (line of sight) area monitors.2 Scope 1.2. ‘‘Entity’’ concept does not apply to the performance Approval of combustible gas detectors.2.3 For intrinsically safe instruments. mobile. instruments used for process control and process monitoring purposes. hazardous (classified) locations as defined by the National Electrical Code® (ANSI/NFPA 70). performance requirements. and a follow-up program.2. 1. 1. FM APPROVALS 1 . NOTE: IT IS STRESSED THAT ALTHOUGH COMBUSTIBLE GAS DETECTORS WARN OF AN EXPLOSION. such as those intended to warn of a drop in concentration from a high value down to the upper flammable limit (UFL). 1.2. examination of manufacturing facility(ies). 1.2. 1. since this is the most commonly used range for instruments intended to measure or monitor the degree of explosion hazard. 6320 1.1. non-flammable toxic gases. INSTALLATION.2. but are not limited to. 9.13. Part I — 2000. The advice of manufacturers.8 FM Approval is limited to instrument applications where: (a) calibration is performed using either the gas to be monitored or another gas for which response conversion data appears in the instruction manual. and/or the standards of other national and international organizations. and (b) the instrument alarm set point is within 10% LFL of the calibration concentration of the gas to be monitored.4.4. trade associations.1 The requirements of this Standard are based on experience.g.6310.1 Examination and tests on production samples shall be performed to evaluate • the suitability of the product • the proper operation and performance of the product as specified by the manufacturer and required by FM Approvals.4 Basis for FM Approval FM Approval is based upon satisfactory evaluation of the product and the manufacturer in the following major areas: 1. for an alarm set point value of 50% LFL.3. gas detectors which do meet all the requirements identified in this standard may not be Approved if other conditions which adversely affect performance exist or if the intent of this standard is not met. 1.3. research and testing. the calibration concentration must be between 40% LFL and 60% LFL. and the marking procedures used to identify the product. testing and marking required by this standard correspond.2. AS SPECIFIED IN SECTION 3. NOTE 1: INSTRUMENT PERFORMANCE TESTING ON COMBUSTIBLE GAS DETECTORS DURING A FM APPROVAL EXAMINATION IS CONDUCTED USING A SINGLE GAS.3. ‘‘Performance Requirements. users. or if the intent of the standard is met.3.2 The construction. 1. jurisdictions and/or loss control specialists has also been considered. Combustible Gas Detectors’’. and strict conformity is not always mandatory.3. • the durability and reliability of the product. 1. 6320 January 2001 1. Combustible gas detectors having characteristics not anticipated by this standard may be Approved if performance equal or superior to that required by this standard is demonstrated.2 An examination of the manufacturing facilities and audit of quality control procedures shall be made to evaluate the manufacturer ’s ability to produce a product identical to that which was examined and tested. These requirements are intended primarily as guides. to ISA S12. 1. These examinations are repeated as part of FM Approvals’ product follow-up program. e.3 Basis for Requirements 1. Alternatively. 2 FM APPROVALS .3 The requirements of this standard reflect tests and practices used to examine characteristics of combustible gas detectors for the purpose of obtaining FM Approval.01. 1. and as far as practical. in general. NOTE 2: IT IS THE RESPONSIBILITY OF THE INSTRUMENT MANUFACTURER TO DEMONSTRATE THE VALIDITY OF RESPONSE CONVERSION DATA DURING THE APPROVAL EXAMINATION PER SECTION 1. INSTRUMENTS WHICH UTILIZE FLAMEPROOF (d) EITHER ENTIRELY OR IN CONJUNCTION WITH INTRINSIC SAFETY.6 Effective Date The effective date of an Approval standard mandates that all products tested for Approval after the effective date shall satisfy the requirements of that standard. ZONE 0. NOTE 1: IN ACCORDANCE WITH THE NATIONAL ELECTRICAL CODE® (ANSI/NFPA 70). Also. visual or physical presentation designed to alert the instrument user that a specific level of combustible gas concentration has been reached or exceeded. FM APPROVALS 3 .) Customary units.8. CANNOT BE APPROVED FOR USE IN CLASS I.8 Applicable Standards 1. and • examination of production samples for continued conformity to requirements. 1. 1.9. Appendix B lists conversion formulas for equivalents in United States (U.8. ONLY INSTRUMENTS WHICH UTILIZE INTRINSIC SAFETY (ia) CAN BE APPROVED FOR USE IN CLASS I. 1. the following terms apply: 1.1 This standard is intended to be used in conjunction with FM Approval Standard 3600 which includes the general requirements that apply to all types of protection for hazardous (classified) locations. 2005 for compliance with all requirements. • the continued use of acceptable quality assurance procedures. as a condition of retaining Approval.9 Definitions For purposes of this standard.S.January 2001 6310. Division 1 or 2 or Class I. • compliance with the terms stipulated in the Approval Agreement. 1. Products Approved under a previous edition shall comply with the new version by the effective date or forfeit Approval.5 Basis for Continued Approval Continued Approval is based upon: • production or availability of the product as currently Approved. The effective date of this Standard is January 1.2 Any portion of a gas detection instrument that is intended for installation or use in a location where gas or vapor concentration is to be detected shall be suitable for use in Class I.1 Alarm: An audible.7 System of Units Units of measurement in this standard are International System (SI) units. ZONE 0. Zone 0. manufacturers may not change a product or service without prior authorization by FM Approvals. 1 or 2 hazardous locations in accordance with the group classification of the gas. 6320 1. • satisfactory field experience. 1. See FM Approval Standard 3600. 9.11 Detector head: The gas responsive portion of a gas detection instrument located in the area where sensing the presence of gas is desired. 1.9. 1.6310. 1. alarm.9. FOR EASE OF REFERENCE. 6320 January 2001 1. THE SHORTER TERM ‘‘GAS’’ MAY BE USED AS AN ABBREVIATION FOR ‘‘COMBUSTIBLE GAS OR VAPOR’’ WITHIN THIS DOCUMENT. can become the fuel for an explosion or fire hazard. in sufficient concentration by volume in air. IT SHOULD BE RECOGNIZED THAT PARTICULAR AUTHORITIES HAVING JURISDICTION MAY PREFER THE USE OF ONE OF THE SETS OF TERMS AND NOT THE OTHER. NOTE: FOR CONVENIENCE. 1. 1. 1. and alarm set point. This unit produces the output function when such gas is present at the detector head location.13 Flammable range: The range of flammable vapor concentrations or gas-air mixtures in which propagation of flame will occur on contact with a source of ignition.10 Control unit: That portion of a gas detection instrument that is not directly responsive to the combustible gas.2 Alarm only instrument: An instrument providing an alarm(s). 1. CIRCUITRY SUCH AS SIGNAL PROCESSING AND AMPLIFYING COMPONENTS IN ADDITION TO THE GAS SENSING ELEMENT (SENSOR).12 Diffusion: A method by which an atmosphere being monitored gains access to the gas sensing element by nature of molecular movement or natural convection.9 Combustible gas: Any flammable gas or vapor that.9. 1.7 Class 6310: FM Approvals designation for all portable gas detectors. 1.9.6 Clean air: Air that is free of combustible gases. THE TERMS ‘‘UPPER FLAMMABLE LIMIT (UFL)’’ AND ‘‘UPPER EXPLOSIVE LIMIT (UEL)’’ ARE DEEMED TO BE SYNONYMOUS. NOTE 1: THE TERMS ‘‘LOWER FLAMMABLE LIMIT (LFL)’’ AND ‘‘LOWER EXPLOSIVE LIMIT (LEL)’’ ARE DEEMED TO BE SYNONYMOUS. 4 FM APPROVALS .9. Materials that cannot produce sufficient gas or vapor to form a flammable mixture at ambient or operating temperatures and mists formed by the mechanical atomization of combustible liquids are NOT considered to be combustible gases.8 Class 6320: FM Approvals designation for all stationary gas detectors.3 Alarm set-point: The selected gas concentration level(s) at which an indication. THE TWO ABBREVIATIONS ‘‘LFL’’ AND ‘‘UFL’’ ARE USED HEREINAFTER TO DENOTE THESE TWO SETS OF TERMS. This procedure is repeated frequently by the instrument user and included in certain tests called for in this standard. vapors or contaminating substances.4 Calibration: The act of adjusting an instrument to ‘‘zero’’ and setting the desired ‘‘span’’.9.9.9. It may be integral with or removed from its control unit. but which does not have an integral meter or other readout device indicating current combustible gas concentration levels. 1.9. or other output function is initiated.9. This may necessitate adjustment of zero. 1. span.9.5 Calibration gas concentration: The concentration of the combustible gas in ambient air used to set the instrument span or alarm set point. but which responds to the electrical signal obtained from one or more detector heads. NOTE: THE DETECTOR HEAD MAY INCORPORATE. IN THE SAME HOUSING. It verifies that the response of an instrument to a known gas concentration is within performance requirements of this standard. supplied and explained in the instrument instruction manual. 1.24 Sample draw: Method by which the atmosphere being monitored is made to flow to the gas sensing element. intermittent-duty instrument: A battery-operated portable or transportable instrument intended for operation during periods of only a few minutes at irregular intervals. FM APPROVALS 5 . gas detection instruments.18 Mobile instrument: A continuously monitoring instrument mounted on a vehicle such as. continuous-duty instrument: A battery-operated portable or transportable instrument intended to operate continuously for 8 hours or more.9. but not limited to. or other output function. normally clean air. FOR EXAMPLE. 1.9. enabling the instrument user to determine the concentration of the gas to be monitored that will produce the same response as a known concentration of another gas used for calibration. personal instrument: Gas detection instrument refers to a batteryoperated. alarm. THE TERM ‘‘INSTRUMENT’’ IS USED AS AN ABBREVIATION FOR ‘‘GAS DETECTION INSTRUMENT’’ WITHIN THIS DOCUMENT.9.9.29 Zero: The lower calibration value.9.21 Portable. 1.25 Span: The algebraic difference between the upper and lower values of a range.20 Portable.January 2001 6310. 1. FLAMMABILITY CHARACTERISTICS OF COMBUSTIBLE GASES OR VAPORS. 1. 1.9. 6320 NOTE 2: THE ACTUAL GAS CONCENTRATION CORRESPONDING TO THE LOWER FLAMMABLE LIMIT OF THE SPECIFIC GAS SHALL BE THE VALUE SHOWN FOR THAT GAS IN THE LATEST EDITION OF NATIONALLY RECOGNIZED DOCUMENTS. 1.22 Range: The operable concentration region of the instrument or a selected subdivision of that region.28 Stationary instrument: A gas detection instrument intended for permanent installation in a fixed location. a mining machine or fork lift truck.16 Gas-sensing element (sensor): The primary element in the gas detection system that responds to the presence of a combustible gas — including any reference or compensating unit. 1.9. 1.9.14 Full-scale gas concentration: The gas concentration that equals maximum scale indication. This may involve a manual aspirator. or other similar systems in which the instrument provides a conditioned electronic signal or output indication to systems of the aforementioned type that typically process information from various locations and sources including. 1.9. signal processing data acquisition.27 Stand-alone detector head: Detector head that is utilized with unspecified control apparatus. an electrical pump or some other means. 1. 1. 1. 1.9. NOTE: FOR CONVENIENCE.9.23 Response conversion data: Information.9.9.9. Such instruments are intended to be interfaced to separate control unit.9. alarm only instrument intended to be operator-worn and to operate continuously for 8 hours or more.9. 1. central monitoring. 1. where applicable.17 Latching alarms: Alarms that once actuated require intentional manual action to reset.26 Stand-alone control unit: Control unit that is utilized with unspecified stand-alone detector head(s). continuous-duty. NATIONAL FIRE PROTECTION ASSOCIATION (NFPA) 325.19 Portable. but not limited to.15 Gas detection instrument: An assembly of electrical and mechanical components (either a single integrated unit or a system comprised of two or more physically separate but interconnected component parts) which senses the presence of combustible gas and responds by providing an indication. the manufacturer ’s specifications and details shall be reviewed to assess the ease and practicality of installation and use. 2. frequency.2 The model or type identification shall correspond to the manufacturer ’s catalog designation and shall uniquely identify the product as Approved.1 In addition to the marking required for general-purpose equipment and by FM Approval Standard 3600.2. Alternatively.4 All markings shall be legible and durable. and 2.2.5 The marking required in 2. All claims not tested and verified by FM Approvals as part of the Approval investigation must be clearly identified as such in the product’s installation and operation manual. features.7 shall appear in a clearly legible. 2.) • Instrument’s operating ambient temperature range • Hazardous location information • FM Approval Mark. etc. the marking shall appear both on the outside surface of the instrument and on its carrying case.1 Review of Documentation During the initial investigation and prior to physical testing. the tests shall be conducted under the conditions for which the claims apply. visible. and permanent manner on each gas detection instrument in the following manner.2.3 The FM Approval Mark shall be displayed visibly on the product and/or packaging as appropriate. the equipment shall be marked with the information required in this Section.7.2. 2. if the latter obscures the marking as required in 2. functions and restrictions included in the FM Approval.2.2.6 and 2. which include the following: • Manufacturer ’s name or trademark and address • Specific model designation and serial number • Instrument’s ratings (voltage. the marking required in 2. The manufacturer shall not use this Mark on any other product unless such product is covered by separate agreement with FM Approvals. The word ‘‘APPROVED’’ associated with the Mark may be supplemented as follows: APPROVED FOR PERFORMANCE AND HAZARDOUS (CLASSIFIED) LOCATIONS 2.2 Markings 2.2. GENERAL REQUIREMENTS 2. 6320 January 2001 2. If any of the manufacturer ’s published claims exceed any of the test condition extremes described in Section 3.6.2.2.6310.6 shall appear in a location where it will be visible after installation and in direct sight during the routine periodic re-calibration and adjustment of set point(s). as applicable: a) For portable instruments.2. b) For stationary instruments. 6 FM APPROVALS . the manufacturer may include a section or appendix in the manual which clearly itemizes the specifications. 2. current or power. 2. installation and periodic servicing of the instrument. Where the design or special nature of the instrument requires additional instructions that are in contradiction of.3 shall be included as applicable.3 that are not intrinsically safe shall be marked: ‘‘CAUTION — THIS AREA MUST BE KNOWN TO BE FREE OF FLAMMABLE CONCENTRATIONS PRIOR TO OPENING THE ENCLOSURE’’ The wording shall be in capital letters at least 5. as close as possible to the control unit. except if routine re-calibration can be accomplished entirely by adjustments at the remote detector locations alone.’’ The word ‘‘CAUTION’’ of the preceding marking shall be in capital letters at least 3. 2.0 mm high and marked in a permanent manner.3. The balance of the wording shall be in capital letters at least 2. of oxygen-enriched or oxygen-deficient atmospheres shall also be included.2.g. FM APPROVALS 7 . Instructions shall be consistent with the markings required in Section 2. 2.5 mm high.8 Instruments of the type referred to in Section 2.5. the requirements of Sections 2.3. but the safety and instructional intent of this Section (2.1 A list of desensitizing or contaminating gases or substances known to the instrument manufacturer which may adversely affect proper operation of the instrument. 6320 NOTE 1: For gas detection instruments that comprise a control unit and remote detector head(s). the additions or revisions are allowed. The instruction manual shall contain clear and precise instructions for safe and proper operation.3.3.2.2 and 2. together with the instructions that it is to be attached by the user in a conspicuous location after installation.3. this marking shall appear both on the control unit and on the remote detector head..5 mm high.2.’’ The word ‘‘CAUTION’’ of the foregoing shall be in capital letters at least 3.3.2 and 2.3.0 mm high. NOTE 3: Where the design of a stationary control unit is such that there is insufficient space for this marking to appear on the portion of the unit that is visible after installation (e. NOTE 2: For modular control units comprising one or more control modules in a common enclosure or mounting assembly. if any.1 Each gas detection instrument shall be provided with an instruction manual. 2.7 Portable gas detection instruments having scales that indicate gas concentrations only below the flammable range shall be marked: ‘‘CAUTION — OFF-SCALE READINGS MAY INDICATE EXPLOSIVE CONCENTRATION. compact designs for close panel mounting). Warning as to the effects.2 The following requirements shall be incorporated in the manufacturer ’s instruction and operation manuals: 2.0 mm high.4.9 Where the design of special features of the instrument requires additional markings or a change in marking requirements.2. The balance of the wording shall be in capital letters at least 2. The requirements of Sections 2.January 2001 6310. 2. the marking required by 2.2) must be met.3 Manufacturer’s Installation and Operation Manuals 2. the marking need not be repeated on each module. provided that a second duplicate label (with an acceptable adhesive) bearing such marking is supplied with each such control unit (or assembly of control units). 2.2.6 is permitted to appear elsewhere on the control unit. furnished by the manufacturer.2.3. or in addition to. but may appear as a single marking on the common portion of the assembly. The marking shall be conspicuously visible prior to removal of the cover. 2.6 All gas detection instruments shall be marked: ‘‘CAUTION — READ AND UNDERSTAND INSTRUCTION MANUAL BEFORE OPERATING OR SERVICING. it is sufficient that this marking appear on the control unit only. this consideration may take precedence over these requirements. 2.13 For alarm only portable gas detection instruments. 2.3. accuracy. response. wording to provide for a clear indication that suitable flow proving devices must be provided at the time of installation. etc.3 Complete installation and initial start-up instructions. SENSITIVITY MUST BE TESTED ON A KNOWN CONCENTRATION OF (specify gas) EQUIVALENT TO 5% LFL ABOVE THE ALARM SET POINT OF THE INSTRUMENT.6310. not requiring special instruments.3. as applicable.3.8 For stationary and mobile sample-draw instruments.3. characteristics of nonlinear meters or indicators.10 For sample-draw continuous-duty portable instruments that are not provided with integral flow indicating devices.9 Wording to provide for a clear indication of the nature and significance of all alarms and trouble signals. wording such as: CAUTION — BEFORE EACH DAY’S USAGE. zero and span adjustments.) 2.2. 2.2.1 above and following exposure to concentrations causing operation of any alarm. 2. voltage range for line powered instruments (nominal voltage may be specified but the range must also be included). following exposure of any of the contaminants referred to in 2. battery charging.2.2. if applicable. SENSITIVITY MUST BE TESTED WITH A KNOWN CONCENTRATION OF (specify gas) EQUIVALENT TO 25% TO 50% OF FULLSCALE CONCENTRATION Also. sample-draw pressure and tubing size.2.2.3.11 For intermittent-duty portable gas detection instruments (of the catalytic detection type). 2. provisions which may be made for silencing or resetting alarms.2.2. as applicable.3. battery life and temperature limitations. and an indication of any alarm devices. OR CORRECTIVE ACTIVE TAKEN PER (specify adjustment procedures) 8 FM APPROVALS .2.2 Instructions of maintenance and calibration on a routine basis. response times.3. etc. outputs or contacts that are of the non-latching type.2.2. loop resistance.5 A list of instrument specifications to include as a minimum: maximum and minimum storage limits of all parts of the instrument. 2.3. alarm set point adjustment. sample-draw range of flow rates and lag times.4 A list of operating adjustments and instructions (e.2.12 For intermittent-duty and continuous-duty portable gas detection instruments. warm-up time. THE ALARM MUST BE ACTUATED DURING THIS CHECK.. sensor life limitation.2.3.6 A list of operational limitations which include. maximum length of lines. which will ensure that sample lines are intact and that proper flow is established.3. 6320 January 2001 2. 2. detailed instructions regarding one or more suitable techniques. air velocity limitations. pressure limits. wording such as: CAUTION — ANY RAPID UPSCALE READING FOLLOWED BY DECLINING OR ERRATIC READING MAY INDICATE A GAS CONCENTRATION BEYOND UPPER SCALE LIMIT WHICH MAY BE FLAMMABLE 2. wording on the action the user should take if after this test the indication is less than the actual concentration.g. duration of any time-limited or self-restoring alarms or signals. wording such as: CAUTION — BEFORE EACH DAY’S USAGE. alarm tolerances and set point limitations.3. 2.7 A statement to the user to be aware that extended exposure of a sensor to certain concentrations of combustible gases in air may introduce stress to the sensor that could seriously affect its performance and that calibration should be carried out and/or the sensor replaced after an alarm due to indication of a high concentration. and humidity and temperature operational limits for all parts of the instrument.3. and minimum wire size for wiring between the control unit and remote detector heads (s) needed for shielding of wiring. 2.3. include a list stating the specific gas family or chemically similar gases for each sensor. If the instrument is designated to monitor gases other than the one for which it is calibrated.3. 2. 2.3.3 (NOTE 2). 4-20 mA signal). the instruction manual shall provide graphs or other means to indicate the relationship between the input and the output.4 For stand-alone detector heads and instruments that provide measurement and alarm outputs (e. 75 and 100% of full-scale indication. In order to maintain an FM Approved system.2.2. the following shall appear in the instruction manual: ‘‘As part of this Approval. and recommendation of the storage type.3.18 If more than one type of sensor is supplied by the manufacturer. 2. This Approval.g. 4-20 mA signal.2. it was verified that optional communication functions of this gas detection instrument while operating at the maximum transaction rate do not adversely affect the gas detection operation and functions of the instrument.3..’’ 2. 25.3. does not include or imply Approval of the communications protocol or functions provided by the software of this instrument or of the communications apparatus or software connected to this instrument.2.3. wording such as: CAUTION — OFF-SCALE READING IN EITHER DIRECTION MAY INDICATE A FLAMMABLE CONCENTRATION 2. 6320 2. the manufacturer shall provide data showing the relationship between the output signal or indication of the instrument and gas concentrations corresponding to 0. As a minimum. Full-scale output shall be as specified by the manufacturer.6 Communication options For instruments providing communications options that are not included in the Approval examination but which comply with requirements of Section 3. the following shall appear in the instruction manual: ‘‘This Approval does not include or imply Approval of gas detector heads or other apparatus to which the subject instrument may connected.15 The type of calibration gas or vapor mixture to be used.2.16 An evaluation procedure to determine the possible sources of malfunction and the corrective action to be taken. specifications shall be supplied with the instrument that describe the relationship of the gas concentration detected by the instrument.17 A listing of consumable or replacement parts. 50. to the corresponding output signal or indication.g.3. relay contacts).19 For instruments which provide measurement outputs (e.14 For instruments provided with meters having scales only above or below the flammable range.January 2001 6310.’’ 2. Such specifications shall be detailed to the extent that the accuracy of the output or signal indication can be verified. In order to maintain an FM Approved system.. 2.’’ FM APPROVALS 9 .3.3 For stand-alone detector heads. 10.3.2. however. the apparatus to which this instrument is connected. the measurement input signal to which this instrument is connected must also be FM Approved. 2.3. must also be Approved by FM Approvals. environment and installation instructions. 2. the following shall appear in the instruction manual: ‘‘This Approval does not include or imply Approval of apparatus to which the subject instrumentation may be connected. include response conversion data with specific instructions as to its use.5 For stand-alone control units. 4.3. 2.1 General requirements 2.4. or that may produce corrosive by-products as a result of catalytic oxidation or other chemical process. or remote detector heads specifically intended for use in the presence of corrosive vapors or gases.4 A means shall be provided to alert the user that a gas concentration in excess of the measuring range of the instrument has been detected.2 Alarm devices or signals of the non-adjustable alarm set-point type shall be set to operate at a gas concentration not higher than 60% of the lower flammable limit. For alarm devices or signals of the adjustable alarm set-point type.3 Continuous-duty portable instruments of the sample-draw type shall incorporate a device to indicate adequate flow.2 Stationary and mobile sample-draw-type gas detection instruments shall be provided with flowproving devices (either integral or non-integral). 2. shall be constructed of materials resistant to or suitably protected against corrosion. If two or more set or alarm positions are provided. or d) down scale indication (below zero) equivalent to 10% nominal LFL or more.1 Gas detection instruments. 2.6310. NOTE: The latching requirement may be omitted or a defeating option permitted only when a clear and prominent statement in the instruction manual specifies that the instrument shall be connected to an auxiliary system which accomplishes the same purposes as latching 2. 2.4. or signal outputs (if provided as part of stationary instruments or continuous-duty portable instruments and intended to indicate a potentially flammable gas concentration) shall be of a latching-type requiring a deliberate manual action to reset.3 Alarm or output function 2. shall be stated in the instruction manual. b) loss of continuity in any one or more conductors to any remote detector head. 2. the means for adjustment shall not be capable of being set higher than 60% of the lower flammable limit.4.4.3.2. when used. c) loss of continuity of any gas-sensing element. which shall produce a trouble signal in the form of a contact transfer or signal transfer if a loss of flow occurs. the lower may be non-latching.3.4. Such signal or contact transfer shall be independent of any other alarm or shutdown signal or contact transfer.4. output contacts. 10 FM APPROVALS . their components.1 A stationary or mobile gas detection instrument shall provide for a signal transfer or contact transfer to produce a trouble signal if any of the following conditions occur: a) instrument power failure.1. indicators and outputs 2.2.4.2 Operational characteristics of nonlinear meters or indicators.4.4. except that such an indicating device may be omitted provided that the instruction manual contains detailed instructions as required by Section 2. 2.2.2.4.1.1 Stationary and continuous-duty portable gas detection instruments having an integral meter or indicator to indicate gas concentrations shall employ a meter having sufficient resolution to permit measurement with the precision required for the tests of Section 3. 2. 6320 January 2001 2. 2.4 Trouble signals 2.4 Construction and Functions 2.4.4.10.2 Meters.4.4.2.4.2 Portable instruments of the sample-draw type shall include the necessary sample-pumping mechanism.1 Alarm devices. that mechanism shall either trip the fault signal and produce a visual indication or provide a similar independent set of signals.6 Batteries 2. If the instrument is provided with a switch that must be manually held in the ‘‘On’’ position for the duration of the measurement.2.g. or controls that may be deliberately or accidentally operated during the calibration procedure shall involve only circuits meeting requirements for nonincendive circuits: and c) All un-insulated parts of circuits exceeding 30 V rms or 42. etc.4.5.5. etc. the duty cycle shall be reduced to 2 min ‘‘On’’ and 18 min ‘‘Off ’’ for a period of 8 h (total cumulative ‘‘On’’ time of 48 min)...) and indications of stand-alone control units or systems must have the ability to be calibrated for zero and span. 2.5. portable gas detection instruments shall be provided with an audible or visible indication of low battery condition.) of stand-alone detector heads must have the ability to be calibrated for zero and span.1 Continuous-duty portable gas detection instruments with fresh or fully charged batteries shall be capable of continuous non-alarming operation for a period of at least 8 h without replacing or recharging batteries. FM APPROVALS 11 . voltage.4. 4-20 mA.5 Controls and adjustments 2. and d) The enclosure shall be marked as described in Section 2. voltage.4.5.8.3 Fixed instruments housed in explosionproof or pressurized enclosures shall have all controls for normal operation accessible from outside the enclosures. and b) All adjustments. etc. current loop. current loop.4.5.5.6.4 V peak or 60 Vdc and of circuits 30 V rms or less that are not Class 2 power limited (as defined by Article 725 of the National Electrical Code® ANSI/NFPA 70) shall be protected from accidental contact by appropriate mechanical guards or partitions.4.4.g. 2.2 Intermittent-duty portable gas detection instruments with fresh or fully charged batteries shall be capable of non-alarming operation at a duty cycle of 10 minutes (min) ‘‘On’’ and 10 min ‘‘Off ’’ for a period of 8 h (total cumulative ‘‘On’’ time of 4 hours) without replacing or recharging the batteries. 2.) provided with detector heads or control units must have the ability to be individually calibrated for zero and span. The controls for routine calibration may be inside the enclosure.2 Calibration and alarm(s) setting shall be designed to discourage unauthorized or inadvertent interference with the setting(s). Examples of acceptable methods include mechanical devices (such as a cover requiring the use of a tool) and passwords (input by authorized users).4.4. 2.4. with or without the presence of a detector head (use of simulated detector head output is satisfactory). with or without the presence of a control unit (use of simulated control unit input is satisfactory).4 If the manufacturer provides a mechanism that will disable alarm outputs for maintenance or calibration purposes.4 Measurement indications and output signals (e.4. 2. provided all of the following requirements are met: a) The enclosure has a cover that can be readily opened or closed and that does not require removal and replacement of bolts or other securing devices in order to open and re-close the enclosure.1 All portable gas detection instruments shall be provided with means for facilitating calibration checks and adjustments as required.6 Auxiliary measurement output signals (e.4.4.3 Continuous-duty.6.5 Measurement input signals (e.4. switches. 2.g.4.January 2001 6310. voltage. 2. 6320 2. and the nature and purpose of either shall be clearly explained in the instruction manual. 2.. 2. . b) The instruments tested shall be fully representative of instruments intended for commercial production. 2.4.4.8 shall be satisfactorily completed prior to the start of tests required in this section and any modifications or changes resulting from those requirements shall be incorporated in the instruments under test. For example.8. intended for outdoor use as specified by the manufacturer shall be tested for such locations. 12 FM APPROVALS .7. 2. to continue combustible gas detection tests shall be considered a failure. including associated accessories. 2.6310. 6320 January 2001 2.1 Instrument enclosures. rain.4.5 Test Equipment Calibration All examinations and tests performed in evaluation to this Standard shall use calibrated measuring instruments traceable and certified to acceptable national standards. etc. hosedown. c) Unwarranted or false alarms shall be considered failure of the tests described below.) shall be considered as part of performance tests in Section 3.7. f) For multiple gas sensing instruments. PERFORMANCE REQUIREMENTS 3. corrosion tests.1 General a) The tests required in this section are in addition to the requirements of applicable standards referred to in Section 1.3 The effects of the tests required to verify the instrument’s suitability for specified locations (dust. etc.7. The converted value(s) shall be used for determination of all deviations from standard requirements. d) All output indications and signals. all unwarranted (false) alarms which require re-setting.4. 3. the conversion of a 4-20mA output to %LFL concentration shall be performed using the following formula: Measurement (%LFL) = [ Im – 4 16 ] Full-scale Where: Im is the measured 4-20 mA loop current in mA Full-scale is the instrument’s maximum range value e) Tests shall be conducted with all equipment installed as intended for use.7 Enclosures 2. NOTE: Examination and tests required in applicable standards in Section 1.2 All parts of the instrument subjected to the combustible gas atmosphere to be monitored shall be suitable for that location. re-adjusting. not directly scaled in %LFL. shall be converted to the applicable %LFL concentration readings. including all necessary interconnections and initial adjustments.12.e.12.15. 3. air velocity variation testing may not be applicable. 3. NOTE 2: For instruments having serial or parallel communications options. 3. 3. tests in Sections 3.4. tests in Sections 3..18 shall be performed with the maximum system communications transaction rate and activity level which would result from the largest and most complex system configuration. with fresh or fully charged batteries.9. Special apparatus may be used to simulate the system activity and must be provided by the manufacturer.4 Conditions for test and test area 3. NOTE 1: For instruments having remote detector heads. NOTE: For stationary or continuous-duty instruments of the sample-draw-type.2 Samples and Sequence One previously untested instrument including all optional or accessory parts to be used on the final Approved instrument shall be subjected to all tests applicable to that instrument type as described in the following sections. tests may be performed in ambient air having a relative humidity of any convenient value in the range of 30 to 70%.6 through 3.3 Preparation of instrument The instrument selected for testing shall be prepared as if for actual service.4.6) NOTE 3: For instruments that are part of a system evaluated for Approval.19. 3.11 through 3. Special apparatus may be used to simulate the communications activity and must be provided by the manufacturer.2 Ambient temperature Except as otherwise indicated herein.9. 6320 3. temperature. The sequence of tests shall correspond to the order of these sections. 3.3 Humidity Except as otherwise indicated herein. supply voltage. and EMI) may be performed at any time after the test described in Section 3.10. air velocity. 3. (See Section 2.10. all tests shall be performed with resistors (with temperature coefficients similar to those of the recommended interconnecting conductors) connected in the detector circuit to simulate the maximum line resistance specified by the instrument manufacturer.3. tests may be performed at conveniently available room ambient temperatures in the range of 18°C to 30°C. but before the test described in Section 3. 3.16 (i. The instrument tested shall be fully representative of instruments intended for commercial production. humidity.16 and 3. if applicable.10. 3.15.17. 3. all tests shall be performed at the nominal system voltage and frequency marked on the equipment.18 shall be performed with all communications ports connected to apparatus which initiates the maximum transaction rate and activity level specified by the instrument manufacturer. The same instrument shall be subjected to all tests applicable to that type of instrument described in Sections 3. EXCEPTION: The tests described in Sections 3. 3. in accordance with the manufacturer ’s instruction manual. FM APPROVALS 13 .1 Voltage Except as otherwise indicated herein. step change.January 2001 6310. 3.4. or.16 and 3. except where minimum line resistance offers a more stringent test. the instrument shall be allowed to stabilize under these new conditions (see note below) before measurements are taken for comparison purposes. including all normally attached diffusion devices or protective mechanical parts.4 Room air circulation Except as otherwise indicated herein.7 through 3.10 Stand-alone gas detection instruments for use with separate control units 3. data acquisition. 3. 3..5 Removal of parts For purposes of the tests in Sections 3. 3. 14 FM APPROVALS .6310.4.9 Instruments having alarms only Instruments having alarms only do not have any meter or other output indication that can be compared before and after the tests described in Section 3. central monitoring or other similar systems which typically process information from various locations and sources including. the alarm set point shall be set at 20% LFL and a tolerance of ±5% LFL applied for all tests.6 Multiple detector heads For stationary.13. Dummy electrical loads (e. 3.4.1 General Section 3. NOTE: An instrument shall be considered to be stabilized when three successive observations of the indication taken at 5-min intervals indicate no significant change.4. For purpose of the test.2 through 3.15. all other heads shall be exposed to normal. in the case of remote detector heads.18.4.4. only one detector head shall be so exposed.7 Re-calibration or adjustment The instrument under test may be adjusted or re-calibrated prior to the start of each test described in Sections 3.8 and 3.18. clean air and normal conditions for tests as described in Sections 3.14. tests are to be performed in relatively still air (not more than 1 meter per second [m/s]) except for those currents that may be induced by convection due to the natural heating of the equipment under test or caused by air-moving devices that are part of the equipment under test. 6320 January 2001 3.4. gas detection instrumentation.4. where reference is made to exposing the sensing head to specified gas mixtures or to other specified conditions. 3.10.10 includes instruments that provide a conditioned electronic signal or output indication intended to be used with separate signal processing. each time the instrument is subjected to a different test condition.4. for tests that call for the exposure of the remote detector head to a specified test gas or other specified set of conditions.4. but not limited to. the entire head.10 through 3.8 Stabilization time For the tests in Sections 3. shall be so exposed. and 3. mobile. 3. 3. However.4. 3. It should be noted that the output indication may differ under conditions of a stagnant sample (sample velocities of 0.1 m/s or less).4. no further adjustments or re-calibration shall be carried out for the duration of that test except where specifically permitted by the particular test procedure.4. fixed resistors) may be substituted for additional heads but if additional heads are used.11. or continuous-duty portable gas detection instruments intended to be used with more than one remote detector head.g. 3.19.4. the tests in Section 3. the performance shall be the same as for the least sensitive range. 3. 25%.11.2 Tests The control units shall be tested to the requirements of Sections 3.1 General Section 3.2. 3. 3.8.8 and 3.1 For instruments having more than one selectable range or scale for the same gas.6.2 For instruments having selectable ranges employing different detecting means. Full scale output shall also be as specified by the manufacturer.9.8. all of these tests shall be performed on each range.3 For instruments having specific ranges or scales for different gases: a) After only one vibration test performed per Section 3.11 includes those instruments to be used with stand-alone gas detection instruments (as defined in Section 3. b) The tests in Sections 3.5 Selectable gas/range instruments 3. As a minimum. equipment shall be provided by the manufacturer to interpret the output signal or indication which will enable the accuracy of the transfer function to be verified.2 Transfer function specification A specification shall be supplied with the instrument that describes the relationship of the gas concentration.4. the tests in Sections 3. If the manufacturer does not state the performance characteristics of the most sensitive scale where it is 25% of LFL or less.4.10.8. 3.11 Separate control units for use with stand-alone gas detection instruments 3. detected by the instrument.11.10 through 3.3 Provision for transfer function verification Where necessary. 3.15.19 using the parameters of the transfer function pertinent to the specific type of gas detector.19 shall be repeated at each selectable range for each gas. Such specification shall be detailed to the extent that the accuracy of this transfer function can be verified. except that if the most sensitive range has a full scale equal to or less than 25% of the LFL. 10%. all parts of the combustible gas detection instrument shall be exposed sequentially to the following conditions: a) Temperature of -35°C for 24 h b) Ambient temperature and humidity for at least 24 h c) Temperature of +55°C for 24 h d) Ambient temperature and humidity for at least 24 h FM APPROVALS 15 . 75% and 100% of full scale output indication. 3.4. 3.5. 50%.11 through 3.4.4. 3.10. 6320 3.3 shall be repeated at each selectable range for each gas.10.4.5.5. 3. to the corresponding output signal or indication (transfer function).18 shall be performed with the instrument operating at both the least and most sensitive ranges. the manufacturer shall provide data showing the relationship between the output signal and the gas concentrations corresponding to 0.10) to complete a ‘‘performance evaluated’’ combustible gas detection system.11.16 and 3.January 2001 6310. 3. the performance shall be that specified by the manufacturer in the instruction manual.6 Un-powered preconditioning storage Prior to tests in Sections 3. 3.9 through 3. 3. there shall be no loose components or damage to the enclosure that could cause a hazard. The instrument shall be vibrated over a frequency range of 10 Hz to 30 Hz at a total excursion of 0. In lieu of the test criteria above. as required by the test procedure described in Section 3. 3.7.2 shall be performed three separate times. capable of producing a vibration of variable frequency and variable constant excursion (or variable constant acceleration peak) with the instrument under test mounted in place. carrier.2 Procedures The remote detector head. the control unit. 3. NOTE: Failures resulting from this test may not become apparent until subsequent tests are conducted. The combustible gas to be used shall be as follows: Methane for instruments intended for sensing methane specifically. 3. or holding devices that are provided as a standard part of the instrument.7.1 This test is applicable only to portable instruments 3.8.7. each time released with a different surface.5 For the tests in Section 3.3 Test criteria The instruments shall not give any false alarms. the control unit. instruments incorporating alarms only shall be actuated by a 24.1 Apparatus The vibration test machine shall consist of a vibrating table. multi-range instruments need to be tested only on one range.6310. 3. 6320 January 2001 3. respectively parallel to the edges of the instrument.9 Calibration The instrument shall be calibrated for testing in accordance with this standard using manufacturer ’s calibration fixture and specified calibration procedures.8. and.to 16-% LFL test gas mixture after this test.8. edge or corner of the instrument facing down at the time of release. the reading shall be accurate within ±5% of full-scale gas concentration after this test.4 The instrument shall be considered to fail this test if it is inoperative after the test. when tested with clean air and the initial calibration mixture. or intended for general-purpose combustible gas detection (including detection of methane) 16 FM APPROVALS .5 mm for a period of 1 hour in each of three mutually perpendicular directions. the instrument (less any removable case) shall be released from a height of 1 m above a concrete surface and allowed to free-fall.to 26-% LFL test gas mixture but not be actuated by a 14.7. This test procedure shall apply to the remote detector head. and all portable instruments shall be mounted on the vibration test machine and vibrated successively in each of three mutually perpendicular directions.7. The calibration gas shall be a nominal 50% of the instrument’s full-scale gas concentration. The rate of change of frequency shall not exceed 100 Hz/min.8 Vibration 3.8.2.7.2 While in the operating mode. and all portable instruments. 3. 3.7 Drop test 3. The instrument shall be mounted on the vibration table in the same manner and position as intended for service using any resilient mounts.3 The test required in Section 3.7. 3. if different. When the apparatus (or the portion under test) has reached the temperature specified in this section.11 Temperature This test shall be performed in a temperature chamber with the capability of holding the apparatus at the specified temperature within ±2°C. then only those tests as described in Sections 3. (See Section 3.’’ 3.1 All test gas concentrations shall be known to a tolerance of ±2% of %LFL value.10. shall not exceed the following: a) for portable or transportable apparatus where the control unit and sensor are used in the same general environment. 49 to 51%. In each case.13.10. and 98 to 100% of the full-scale gas concentration. For ease of reference. the instrument’s response utilizing this method and the instrument’s intended method of gas monitoring. shall first be established.4.18 need to be repeated for the second and subsequent gases. 3.10. ‘‘Methane’’ shall be tested first if a methanesensing element is supplied by the manufacturer. 3. NOTE: As part of this test. NOTE 3: Gas mixtures having the same concentrations as those used for tests in Section 3. The variation of the indication from that at +20°C.January 2001 6310.3 For instruments having alarms only. 3. and 3. 3.10 Accuracy 3. over the specified temperature ranges. such gas mixtures will hereafter be referred to simply as ‘‘the initial calibration gas mixture. as appropriate. testing shall verify that each alarm 1) actuates on exposure to gas-air mixtures whose concentrations are at the upper tolerance limit for alarm actuation. 3. +20°C and +40°C. 3. the variation over the temperature range -10°C to +40°C shall not exceed ±5% of the measuring range or ±10% of the indication. alarm functions shall be verified to actuate within ±5%LFL when respective set-point values are crossed. 74 to 76%. and 2) does not actuate on exposure to mixtures whose concentrations are below the lower tolerance limit. 3. NOTE 2: Unless otherwise indicated herein. whichever is greater. The dew point of the air or the standard test gas shall be below the lowest temperature of the test chamber and kept constant during the test. FM APPROVALS 17 .) 3.12. the gas sensing element (sensor) shall be exposed sequentially to air and the standard test gas. whichever is greater. 24 to 26%.9.2 The sensing head shall be exposed to five gas concentrations falling in each of the following ranges: 9 to 11%.10. the manufacturer ’s calibration device is to be used to supply the gas mixture to the gas-sensing element for the tests described in the paragraphs that follow.9. the concentration indicated by the meter or output signal shall not vary from the known test gas concentration by more than ±3% of full-scale gas concentration or ±10% of applied gas concentration. Tests shall be carried out at temperatures of -10°C.17.14. which shall be at the same temperature as the atmosphere in the test chamber.11. However.9 are used for various other tests described in the paragraphs that follow. 3.8. 6320 Propane for instruments intended for general-purpose combustible gas detection that excludes methane The actual specific gas or a representative gas for instruments intended for sensing a specific combustible gas or a specific family of chemically similar combustible gases NOTE 1: When instruments can be used for detecting more than one combustible gas by changing only the gas-sensing element. Set-points may be set at convenient values over the instrument range 3. NOTE: Relative humidity values are to be accurate within ±5 relative humidity percentage points. and when optional readout capability is not offered. 2) Control units With the sensor or detector head under normal ambient test conditions. but shall be actuated by 24 to 26% LFL test gas while exposed to both humidity extremes. whichever is greater.13 Humidity variation The instrument shall first be calibrated. An alarm set to 20% LFL of the mixture shall respond within 10 s of exposure to the step change. c) for fixed apparatus with sensors or detector heads and control units in the same general environment. 18 FM APPROVALS . the time is to be measured from the time of starting the first manual aspiration. the following temperatures shall be applied: 1) Sensors or detector heads With the control unit under normal ambient test conditions. The meter or output indications during these exposures shall not vary from the 50% relative humidity exposure indication by more than 10% of full-scale concentration.12. The sensing head shall then be exposed for 2 h to the calibration gas mixture having a relative humidity of 10%.1 Beginning in clean air.2 When instruments incorporating alarms only are tested. For manually aspirated instruments without a sampling line. the sensor or detector head shall be tested in air and in the standard test gas at -25°C and +55°C. then the gas-sensing element shall be exposed to the initial calibration gas mixture at a relative humidity of 50% for 2 h. 3. where the control unit and the detector head or sensor are not used in the same general environment. 3. the above time does not include the transport time required for the gas sample to reach the instrument from a remote sampling point. the gas-sensing element shall be suddenly exposed to a 100% LFL gas-air mixture.1: Beginning in clean air. whichever is greater. The variation shall not exceed ±10% of the measuring range or ±20% of the indication. the gas-sensing element shall be suddenly exposed to a prepared mixture of gas-in-air having a concentration corresponding to 100% of full-scale gas concentration. the variation at +5°C and +55°C shall not exceed ±5% of the measuring range or ±10% of the indication. the variation at -10°C and +55°C shall not exceed ±5% of the measuring range or ±15% of the indication. the instrument shall respond to provide an indication of 60% of full-scale gas concentration within 12 s. For instruments incorporating alarms only. 3. Next the gas sensing element shall be exposed for 2 h to the calibration gas mixture to which water vapor has been added to raise the relative humidity to a final value of 90%. whichever is greater.12. 6320 January 2001 b) for fixed apparatus with remote sensors or detector heads. the alarm shall not be actuated by 14 to 16% LFL test gas.6310. the following clause shall be substituted for Section 3.12. NOTE: For sample-draw-type instruments.12 Step change response 3. From the instant of exposure to this gas mixture. 4.3. As a result of this test. there shall be no instrument malfunction or actuation of the alarms that would falsely indicate the presence of combustible gas.January 2001 6310. The meter or output indication during exposures to the mixture in motion shall not vary from that observed during exposure to the still gas mixture by more than +10% or -5% of full-scale gas concentration in the orientation that causes the greatest deviation.2 through 3..14.e.4. and from nominal to 87.2 For ac-powered instruments.5 m/s.5% of nominal voltage. there shall be no malfunction or interruption of the instrument alarms. It shall then be exposed to the initial calibration gas mixture in motion so as to impinge on the gas-sensing element with a velocity of 5 ±0. the sensing head shall be exposed to clean air.2 to 3.8. The variation in the meter or output indication from actual concentration shall not exceed ±2% of full-scale gas concentration.5% of nominal voltage. the voltage variation shall correspond to the maximum terminal voltage of a fresh or fully charged battery(ies) and the minimum recommended operating voltage of that (those) battery(ies). the supply voltage shall first be decreased to 85% of nominal line voltage and then increased to 110% of nominal line voltage. NOTE: The method of causing these step changes in voltage shall be such as to simulate the effect of a heavy load being added to or removed from the source of supply. 3. (See Sections 3.4.e.8. 3.4.5 s and 5 s. The test shall be repeated with the sensing head exposed to 90% of full scale concentration.9).4).14 Air velocity variation 3. gas detection instruments intended for operation from an external ac power source shall be subjected to momentary power interruptions of approximately 0.15. there shall be no actual interruption of the voltage supply during the voltage transition.1 The instrument shall be calibrated first with the gas-sensing element exposed to a still (ref. Intermittentduty portable instruments having provision for adjustment to compensate for battery voltage decline may be so adjusted.5 For instruments incorporating alarms only. the alarm shall not be actuated on 14 to 16% LFL test gas but shall be actuated on 24 to 26% LFL test gas while exposed to the mixture in motion 5 ±0.4. During this test.15 Supply voltage variation 3.5 m/s in all orientations.15.) Adjustable alarms shall be set to operate at 10% of the LFL or 10% of full-scale concentration. FM APPROVALS 19 . i.15.4) mixture of the initial calibration gas. there shall be no actual interruption of the voltage supply during the voltage transition. NOTE: The method of causing these step changes in voltage shall simulate the effect of a heavy load being added to or removed from the source of supply.4. 6320 3. the detector head shall be exposed to clean air (see Sections 3.1 For gas detection instruments intended for operation on ac power supply systems and with the gassensing element exposed to the initial calibration gas mixture (see Section 3. 3.15.15.4 For self-contained battery-operated instruments.) 3. whichever is lower.3 Gas detection instruments intended for operation from an external dc power source shall be subjected to a step-change in supply voltage from nominal to 122. NOTE: For test purposes.) 3.2 For instruments incorporating alarms only. incorrect functions shall not occur when the primary power is applied or removed. or at the lowest possible setting if this setting is greater.15. Section 4. (See Section 3. During this test.4..4. 3. the alarm shall be actuated by 24 to 26% LFL test gas.14. i. and alarms set in the same manner as for Section 3. as determined by a built-in battery-condition indicator. while exposed to both voltage variation extremes. (See Section 3. but not 14 to 16% LFL test gas. As a result of this test. electronics. and installation techniques as they pertain to electromagnetic interference.17 Long-term stability NOTE: Repeat applicable accuracy tests (Section 3.3).. and interconnecting wiring). repeat the accuracy test procedure in Section 4. Tests shall be conducted for both items 1) and 2) above.16 Electromagnetic Interference (EMI) Following satisfactory completion of all the applicable tests of the preceding clauses.7): a) Clean air at ambient temperature and humidity for six continuous days. except that the maximum allowable deviation shall not vary from the known test gas concentration by more than ±4% full-scale gas concentration or 12% of the applied gas concentration. d) Expose the gas-sensing element to clean air at ambient temperature and humidity for 24 h.6310. the indicated concentration shall be noted and shall not deviate from the actual calibration gas concentration by more than ±10% of full scale for the remainder of the 24 h. and interconnecting wiring) shall be subjected 1) while in an energized (operating) mode and 2) while in the position of normal calibration. 3. the instrument may be zeroed and re-calibrated prior to the final accuracy test of e). shielding. c) Repeat a) and b) a total of four consecutive times (total of 28 days).4. the indicated concentration shall be noted and shall not deviate from the actual calibration gas concentration by more than ±10% of full scale. 20 FM APPROVALS .17. (See Sections 3. 6320 January 2001 3. the instrument may be zeroed and re-calibrated.10. whichever is greater.4. Tests should be conducted following the manufacturer ’s suggestions concerning wiring. Within 5 min after start of the test. its sensor. and the indicated concentration observed after 5 min shall not deviate from the actual gas concentration by more than ±10% of full scale. expose the gas-sensing element to the initial calibration gas mixture for a period of 24 h. NOTE: Following the deviation check at the end of the 14th and 28th days. Just prior to the end of the 14th and 28th days. 3.10) before performing the test under this section. NOTE: Following the deviation check at the end of d). while the gas-sensing element is still exposed to the initial calibration gas mixture. using frequency-modulated portable radio transmitters (5 W input to the final amplifier) at a distance of 1 m away from the instrument (i.4. using a randomly selected frequency within each of the two frequency ranges. to electromagnetic energy in the frequency ranges of 150 to 170 MHZ and 450 to 470 MHZ. b) At the beginning of the seventh day. the gas-sensing element shall be exposed to the initial calibration gas mixture.2 and 3. electronics. These tests shall not cause the instrument to produce output changes of more than 10% of full scale or result in an incorrect instrument function. At the end of this period.e. the stationary or mobile instrument (including sensor.1 Stationary instruments The gas-sensing element shall be consecutively subjected to the following sets of conditions for the periods stated (Section 3. e) Immediately after completing d) (total elapsed time for tests a) through d) is 29 days). A suitable dc power supply may be used for the remainder of the test. except that the actual batteries specified for the instrument shall be used for the first 8 h of a). each cycle consisting of 8 h with the instrument ‘‘On.7): a) The gas-sensing element shall be exposed to clean air at ambient temperature and humidity for six cycles of operation.’’ followed by 16 h with the instrument ‘‘Off ’’ (total elapsed time of 24 h per cycle). NOTE 2: For instruments using rechargeable batteries. 6320 3.2 Continuous-duty portable instruments The instrument shall be consecutively subjected to the following sets of conditions for the periods stated (see Section 3. 1) In lieu of the accuracy tests above.’’ e) Immediately after completing d) (total elapsed time for test a) through d) is 28 days and 6 h). NOTE 3: Zero and span adjustments are permitted prior to each stipulated 8 h ‘‘On’’ period. instruments incorporating alarms only shall not be actuated by exposure to a 14 to 16% LFL test gas mixture and shall be actuated by a 24 to 26% LFL test gas mixture after completing d). a vacuum pump having an equivalent flow may be utilized. FM APPROVALS 21 . including just prior to the final evaluation. the gas-sensing element shall be exposed to the initial calibration gas mixture for a period of 8 h with the instrument ‘‘On.17. d) The gas-sensing element shall be subjected to clean air at normal ambient temperature and normal humidity for an additional period of 6 h with the instrument ‘‘On.January 2001 6310. except that each 8-h ‘‘On’’ period shall consist of 24 cycles of 10 min ‘‘On’’ and 10 min ‘‘Off. repeat accuracy test procedure of 3.17.’’ following which it shall be exposed to clean air at ambient temperature and humidity with the instrument ‘‘Off ’’ for a period of 16 h. The indicated concentration shall be noted over a period of 5 min and shall not deviate from the actual calibration gas concentration by more than ±10% of full scale. 2) The test described in e) shall be performed immediately after the 6 h test of (d) and shall be completed in not more than 2 h so that the total elapsed instrument ‘‘On’’ time for tests d) and e) does not total more than 8 h. a suitable dc power supply may be used or fresh batteries may be installed at the start of each of the 8 h ‘‘On’’ periods. b) At the beginning of the seventh day. whichever is greater. the same rechargeable battery shall be used for the entire test sequence of a). except that the maximum allowable deviation shall not vary from the known test gas concentration by more than ±4% of full-scale gas concentration or 12% of the applied gas concentration. NOTE 1: For instruments using replaceable (non-rechargeable) batteries.’’ NOTE 1: Manually aspirated-type instruments shall be aspirated continuously during each 10-min ‘‘On’’ period. alternatively.10. 3.4.2. NOTE 2: Instruments having provisions for voltage adjustments to compensate for battery voltage decline shall be adjusted as necessary during the above tests.3 Intermittent-duty portable instruments Intermittent-duty portable instruments provided with a switch that must be manually held in the ‘‘On’’ position shall be subjected to the same test sequence and evaluation as described in Section 4. c) Repeat a) and b) a total of four consecutive times (total elapsed time of 28 days).17. The instrument shall produce an output indication corresponding to a concentration of at least 60% of the lower flammable limit or to full-scale concentration. 3. they are aspirated at the rate that is recommended by the manufacturer with the sample inlet connected to a source of 100% gas by volume. the following shall be substituted: Beginning with the gas-sensing element in clean air.2 Manually aspirated instruments shall be subjected to a test whereby. During this test. within 10 s of exposure to the 100% gas-byvolume.18.1 and 3.2. due to its vapor pressure properties. A re-test following a failure shall be acceptable only at the discretion of FM Approvals and with a technical justification of the conditions or reasons for failure. at the discretion of FM Approvals.18.2. cannot be obtained. NOTE 1: For sample-draw instruments of other than the manually aspirated type. 3. (See Section 2. whichever is lower.18.3 During the tests of Sections 3.18 Flooding with undiluted gas 3. the times given above do not include the transport time required for the gas sample to reach the instrument from a sampling point. another appropriate gas may be used for the tests in Sections 3. depending on design features and results of any foregoing tests. the instrument shall produce an output indication corresponding to at least 60% of the lower flammable limit or to full scale.18. whichever is lower. these shall be set to the 60% of lower flammable limit set point or to the highest adjustable set point. within 10 seconds. it shall be subjected to a step change in gas concentration from clean air to 100% gas-by-volume.4 When instruments incorporating alarms only (without an optional readout capability) are tested. using the shortest possible sample tube. if the instrument is provided with audible or visible alarm signal devices or alarm contacts.18.2) 3.18.18. 6320 January 2001 3. and shall be actuated as a result of these tests.3.19 Additional Tests Additional tests may be required. NOTE 2: For detection of vapors whose properties are such that the concentration.1 and 3.6310. An alarm set to 20% LFL of the mixture shall respond within 10 s of exposure to the undiluted flooding condition.18. 3.1 The gas-sensing element of instruments other than the manually aspirated type shall be subjected to a step change in gas concentration from 0% (clean air) to 100% gas-by-volume. 22 FM APPROVALS .2. whichever is lower. The manufacturer shall assign an appropriate person or group to be responsible to obtain FM Approvals authorization of all changes applicable to Approved products. as appropriate: • engineering drawings • engineering change requests • engineering orders • change notices. Conformance to design is verified by control of quality on the following areas: • existence of corporate quality control guidelines • incoming quality assurance. FM APPROVALS 23 . 4. Design quality is determined during the examination and tests. Changes to critical documents.1.1 Demonstrated Quality Control Program 4.2. Quality of performance is determined by field performance and by re-examination and test. conformance to design. Records of all revisions to all Approved products shall be kept. 4. must be reported to. procedures. FM Approvals Form 797. 6320 4.1. 4. including testing • final inspection and tests • equipment calibration • drawing and change control • packaging and shipping. OPERATIONS REQUIREMENTS 4.2 Facilities and Procedures Audit (F&PA) 4.1 An inspection of the product manufacturing facility shall be part of the Approval investigation. Its purpose shall be to determine that the equipment. and authorized by. Approved Product Revision Report or Address/ Contact Change Notice is provided to notify FM Approvals of pending changes.1. identified in the Approval Report. 4. including.3.January 2001 6310. FM Approvals prior to implementation for production. These shall be executed in conformance with a written policy and detailed procedures.2 The manufacturer shall establish a system of product configuration control to prevent unauthorized changes. including testing • in-process quality assurance.2 Unannounced follow-up inspections shall be conducted to assure continued quality control and product uniformity. and manufacturer ’s controls are properly maintained to produce a product of the same design quality as originally verified.2. Design quality. and performance are the areas of primary concern.1 A Quality Control Program is required to assure that each subsequent unit produced by the manufacturer shall present the same quality and reliability as the specific samples examined. A.6310. • Quality Control Procedures document(s) detailing routine testing and final inspection procedures. • document number or other form of reference number identification. 2) determining what test samples will be required for the test and examination program. • Production Drawings • Electrical Schematic(s) • Final Assembly drawing and parts lists • Sub-assembly drawings or piece-part drawings/assembly drawings sufficient to detail primary circuit components.. one copy will be sufficient at the beginning of a program but 15 copies may be necessary for use as report attachments at the conclusion of the program. and maintenance instructions. For the purposes of 1) assessing compliance of equipment with FM Approval requirements. and safety interlocks. • Model Number Breakdown drawing or sales specification sheet showing all model variations and options to be examined. and 3) providing a means for design modification control. PO Box 9102. U. Typically. MA 02062. • Marketing/Ordering Literature showing general specifications and functions of the equipment. One copy (except as noted) of the following documentation as it pertains to the Approval request should be assembled in an organized manner and submitted prior to scheduling of the test program. All documents shall identify the following: • the manufacturer ’s name. 1151 Boston-Providence Turnpike. These are generally very useful in determining project costs and may also be used as attachments to the final report for equipment Approval projects. 24 FM APPROVALS . 6320 January 2001 APPENDIX A GENERAL INFORMATION A-1 Approval Application Requirements To apply for an Approval examination the manufacturer. NOTE: DRAWINGS IN A LANGUAGE OTHER THAN ENGLISH MAY REQUIRE PARTIAL TRANSLATION FOR USE IN AN APPROVAL PROGRAM. Norwood.e. or its authorized representative. number or letter indicating revision level). enclosure design. operation. • Instruction Manual(s) providing installation.S. the manufacturer shall submit documents which give a full and correct specification of the critical construction aspects of the equipment. operator controls. • title. Each model variation must have a unique means of identification. and • date of latest revision of document and/or the revision reference (i. NOTE: TEST PROGRAMS WILL BE SCHEDULED ONLY UPON RECEIPT OF ALL THE MATERIAL LISTED HEREIN. should submit a request to the Electrical Group Manager at FM Approvals. The label drawing should show proposed artwork indicating the manufacturer ’s name. i. IEC/CB Scheme reports.e. model and serial numbers. • Documentation Control Specification showing proposed method of controlling documents which may be identified as Critical Documents by FM Approvals. equipment ratings. results of prior or similar testing. and results of any foregoing tests. Certification reports. component recognitions. A-2 Requirements for Samples for Examination A-2.January 2001 6310. • Protective Grounding Detail drawing(s) showing the method of protective grounding provided. A-2. address. warning markings.2 Requirements for samples may vary depending on design features. ‘‘Approved Product Revision Report’’. etc. • Any Approval documents from other Nationally Recognized Testing Laboratories (NRTL’s) or National Certification Bodies (NCB’s) needed to support an FM Approval process.. IEC/CCA reports. Listing reports. and the FM Approval mark. such as those which may be required to evaluate the subject apparatus. 6320 • Product label drawing(s) showing all required marking information. the manufacturer will be required to submit samples for examination and testing based on requirements to be determined by FM Approvals during the review of the preliminary information. A-2. size. Any decision to use data generated utilizing prototypes is at the discretion of FM Approvals. FM Approvals must be notified of changes to these documents via Form 797. including location. FM APPROVALS 25 . and marking.1 Following authorization of an Approval examination. These drawings will be identified by FM Approvals at the conclusion of the Approval program.3 The manufacturer shall submit samples representative of production.4 It is the manufacturer ’s responsibility to provide any necessary test fixtures. A-2. 2808 26 FM APPROVALS . 6320 January 2001 APPENDIX B UNITS OF MEASUREMENT LENGTH: mm – ‘‘millimeters’’ inches = mm × 0.03937 m – ‘‘meters’’ feet = m × 3.14504 bar – ‘‘bar ’’ kPa = 100 bar psi = bar × 14.503 TEMPERATURE: °C – ‘‘degrees Celsius’’ °F (degree Fahrenheit) = (°C × 9/5) + 32 FLOW RATE: lpm – ‘‘liters per minute’’ ft3/min (cubic feet per minute) = lpm × 0.2808 PRESSURE: kPa – ‘‘kilopascals’’ psi (pounds per square inch) = kPa × 0.035315 VELOCITY: m/s – ‘‘meters per second’’ ft/s (feet per second) = m/s × 3.6310.