Chennai Metro Rail Project, No.53, Habibullah Road, T-Nagar, Chennai - 600 017 TamilNadu, INDIA 1 DOCUMENT TECHNICAL VERIFICATION AND REVISION RECORD Project Name DOC/TITLE REV NO. DATE OF ISSUE Design and Construction of Underground Stations at Gemini, Teynampet, Chamiers Road and Saidapet and Associated Tunnels Contract UAA03 Safe operation procedure for working at Height DESCRIPTION PREPARED/ DESIGNED CHECKED APPROVED A0 19/12/11 Safe operation procedure for working at Height Amit Ninawe Manas R. Mohanty Mahesh Chaturvedi Prepared by Checked by Approved by Amit Ninawe HSE Manager Manas R. Mohanty Chief HSE Manager Mahesh Chaturvedi Project Manager 2 WORKING AT HEIGHT 1.1 Introduction 3 GIL-MMS JV is committed to minimize the risk associated with Working at heights. requirement relating to fall protection working on Scaffolds, Cranes, Derrick, performing steel erection work, certain types of equipments used in tunnelling operations, engaged in the construction of electrical transmission and distribution lines and working on stairways and ladders. 1.2 General The standard operation procedure will explain the requirements and criteria for fall protection. Work places, conditions, operations and circumstances for which fall protection shall be provided. To ensure that work at height is carried out safely and that persons performing the work do not endanger themselves or other persons who may be exposed to the hazards of falling objects. This procedure applies to all working at height on this project. 1.3 Definition Work at height is any place of work where a person could be injured by falling from it and includes a place at or below ground level. 1.4 General Safety Requirements • The rule sets a uniform threshold height of (2 meters), thereby providing consistent protection. • GIL-MMS JV must protect their employees from fall hazards and falling objects whenever an affected employee is (2 meters) or more above a lower level. • Protection also must be provided for construction workers who are exposed to the hazard of falling into dangerous equipment. • GIL-MMS JV must assess the workplace to determine if the walking or working surfaces have the strength and structural integrity to safely support workers. • Select the proper fall protection system to protect exposed employees at 2 meter or more. • Provide proper training. 4 Working at Height 1.5 Fall Protection Systems 1.5.1 1.5.2 1.5.3 1.5.4 1.5.5 1.5.6 1.6. Guardrail Systems. Personal Fall Arrest Systems. Positioning Device Systems. Safety Monitoring Systems. Safety Net Systems. Warning Line Systems. Guardrail Systems • The top edge height of top-rails must be 42 inches (1.1 meters) above the walking/ working level. • Screens, mid-rails, mesh, intermediate vertical members must be installed between the top edge of the guardrail system and walking/working surface (at least 21 inches (53 cm) high. • The guardrail system must be capable of withstanding a force of at least 200 pounds applied on the top from both directions. • Guardrail systems shall be surfaced to protect workers from punctures or lacerations and to prevent clothing from snagging. • Maximum Distance Between Vertical Posts not to exceed 8 Ft. (2.4 m) • The guardrail should be installed very close to the edge, maximum distance not more than 30 cm (300 mm) 1.6.1 Personal Fall Arrest Systems 5 • These consist of an anchorage, connectors, and body harness. It must do the following: • Be rigged so that an employee can neither free fall more than 2 meters nor contact any lower level. • Bring an employee to a complete stop and limit maximum deceleration distance an employee travels to1.07 meters. • Have sufficient strength to withstand twice the potential impact energy of an employee free falling from a distance of 2 meter or the free fall distance permitted by the system, whichever is less. • The use of Safety belts for fall arrest is prohibited and a full body harness with/without shock absorber is required on this project as required by the employer (client). • Must be independent of any platform anchorage and capable of supporting at least 5,000 lbs per worker. • All full body harness must be inspected every month. Leather and webbing should be inspected for cuts, cracks, abrasions, or tears and any sign of undue stretching. Snap hook should be examined for signs of damage, distortion or faulty spring. Lanyard should be inspected for damage and signs of wear. A record of inspection should be maintained. • The wearer should make a visual inspection daily before use. • Full body harness should be stored in a cool, dry, well ventilated place away from direct sunlight and free from contact with anything that could cause damage. 1.6.2 Positioning Device Systems • Full body harness are to be set up that a worker can free fall no farther than 2 feet. • Secured to an anchorage capable of supporting 3000 pounds (1400 kg). 1.6.3 Safety Net Systems 6 • Safety nets must be installed as close as practicable under the walking/working surface and never more than 30 feet (9.1 m) below such levels. • Installed with sufficient clearance underneath to prevent contact with the surface or structure below. • Each Safety net or section shall have a border rope for webbing with a minimum breaking strength of 5000 pounds (2300 Kgs). • Safety nets shall be inspected at least once a week for wear, damage, and other deterioration. • Items that have fallen into safety nets including – but not restricted to, materials, scrap, equipment, and tools – must be removed as soon as possible and at least before the next work shift. 1.6.4 Safety Monitoring Systems • Used when no other alternative fall protection has been implemented. • Competent person to monitor the safety of workers. • The GIL-MMS JV shall ensure that the safety monitor is competent in the recognition of fall hazards. • Is capable of warning workers of fall hazard dangers and in detecting unsafe work practices. • Is operating on the same walking/working surfaces of the workers. • Have no other duties to distract from monitoring function. • No mechanical equipment shall be used or stored where safety monitoring system are being used. 1.6.5 Warning Line Systems • • • Flagged at not more than 6 foot intervals with high visibility materials. Rigged and supported so that the lowest point including sag is no less than 34 inches (0.9 meters) from the walking/working surface. Shall be erected around all sides of roof work areas. 7 1.7 • • • • • • • • • Stairways and Ladders Site made or damaged ladders are not allowed Angle of the ladder should be kept within prescribed limits Firm and secure ladders to prevent slipping, fasten from 3 points. Do not splice together short ladders to make a longer ladder While work in traffic areas, barricade or tape off the area around ladder. Do not use the top two steps on step ladders Inspect daily and do not over-load while on ladder. Maintain three points of contact (hands and feet) whilst in the working position. Ladders used for access to another level should be tied and extend at least 1m above the landing point, .and are in positioned where they cannot be pushed over by opening doors or windows. • • • Pedestrians are stopped from walking underneath them or close to their base by making use of barriers. Ladder is placed at the correct angle of 750 The ladder or stepladder use is not within 6m horizontally of any overhead Power lines, unless they are made temporarily dead or protected with insulation For live electrical work use non-conductive ladder & one person at a time. • • • • Must wear robust, suitable non-slip footwear free from contaminants. Do not use painted ladder as the paint may cover defects and damage! Do not move ladders/stepladders while standing on the rungs/steps. When using extension ladders, the overlap of two adjacent sections should be ensured by 1 ½ rungs for 5m ladder, 2 ½ for 5m-6m ladder, 3 ½ over 6m ladder. Proper locking mechanism should be provided. • • All ladders must extend at least 1 meter above any landing place or beyond the highest rung from which a man may be working, to ensure adequate handhold. Wooden ladder are not allowed. 1.8 Openings and Holes • • Covers the holes in floors, roofs, and other walking/working surfaces. Covers located in roads ways and vehicular aisles shall be capable of supporting, without failure, at least twice the maximum axle load of the largest vehicle expected to cross over the 8 cover. • • • All other covers shall be capable of supporting, without failure, at least twice the weight of employee equipment, and materials that may be imposed on the cover at any one time. All covers shall be secured when installed so as to prevent accidental displacement by the wind, equipment or employees. All covers shall be marked with the word “Hole” or “Cover” 2.0 Mobile Elevated Working Platform. Power operated mobile elevated working platform provide an alternative to scaffolding when a working platform is required at height. Regardless of type, a number of safety features and precaution should be common to all. These includes • • • • • • • • • • • • • Firm level ground on which to operate. Operator control on platform level with override at ground level in emergency only. Platform properly guarded by guard rails and toe board and with safe means of access. Leveling device on the chassis to ensure verticality in use Stability in use must be ensured Allowance must be made for the effect of wind. Danger from overhead electric lines must be avoided. Operator must be trained by third party as per approved operating procedure and the manufacturer’s manual. Untrained unauthorized use of work platform should not be allowed and operator should lock their machines in a safe, out of service position when they leave them. The equipment must be load tested by a competent person once in every 6 months. The safe working load must be clearly marked on the platform and adhered to. The operator must inspect the equipment everyday before starting the work. Locking of wheels or use of outriggers must be in accordance with the manufacturer’s instructions. Adequate sole plates should be used under the outrigger bearing pads where necessary. • Persons should not be normally leave the platform whilst in an elevated position, nor should materials be transferred. If the equipment is used to transfer persons or goods from one level to another (I,e not as working platform) it may be deemed a hoist or lift and, as such, the elevant regulations would apply. 9 3.0 Scaffold 3.1 General The purpose of this procedure is to ensure that people who are engaged in scaffolding operations, involving working at heights, and any person who may be affected by their activities. e.g. members of the public are adequately safeguarded at all times. This procedure is applicable to all activities where people are working at height, where they and materials may be liable to fall from 2 metres or more . 3.2 Definitions Abbreviations and Acronyms 3.2.1 Compete nt Person A person, who is, trained, certified (BY 3rd Party Training Provider approved by General consultant) and qualified and with experience to enable those to supervise and control work operations with scaffold structures, for inspection, erection and dismantling. 3.2.2 Ledger - Longitudinal tube fixed parallel to the structure to support the transoms. 3.2.3 Transoms - Tube spanning the Ledgers that support the working platforms. 3.2.4 Standard s - Vertical tubes that carry the weight of the scaffold and its loads. 10 3.2.5 Buttress - Inclined tube arrangement which widens the base dimensions of the scaffolds its stability. 3.2.6 Brace - A tube fixed diagonally to increase the stability of a scaffold. 3.3 Provision All work on Scaffolds must take into consideration the requirements of the Indian standard. Where work cannot be done in a safe manner from the ground or the structure then the provision of suitable access equipment will be required. e.g. Access scaffolds. 3.4 GIL-MMS JV Scaffold Competent Person Third party trained and appointed Scaffold Competent Persons will check, supervise and inspect all access scaffolds and platforms on the project. The GIL-MMS JV Competent person/ scaffolders are trained to erect and supervise basic scaffolds such as access and simple works platform erection and inspections only. Any false works is beyond the knowledge of the competent person/ scaffolders. This will be subject to different regimes of design and inspection by qualified structural engineers / designers and checked, inspected and certified by them. 3.5 11 Scaffolds In order to ensure that a scaffold will meet the working requirements for which it is being erected, the following requirements must be addressed: 1. Scaffold must only be erected, dismantled or altered under the supervision of ‘Competent Persons’. Competent persons maybe someone formally appointed or one who has undergone training appropriate to the safe provision and use of scaffold. 2. All the materials that are to be used in the scaffolding must be checked and inspected for safe condition (by competent person) before they are used and if found to be defective, then taken out of use. 3. The bases on which the scaffold is erected sound and capable of distributing the load. Where necessary ground / mud sills and adjustable base plates may have to be planned and positioned prior to erection of the scaffold. 4. Scaffolding are not to be removed or interfered in any way, especially ties, guardrails toe boards, ladders and rakers. Only the qualified scaffolders and competent person are qualified and responsible for such tasks. 5. Damaged scaffold are not to be used while under erection and dismantling. Warning notices including the Red tags are to be clearly displayed as appropriate. 6. Deficient scaffolding is to be reported to the Competent Person as soon as possible. Clear passageway is to be provided when stacking scaffold. 7. The standards and ledgers must be in line, and the standards must be vertical, and they must not lean away from the structure under any circumstances. Where joints are used they must be staggered, both horizontally and vertically. 12 8. The transoms must be correctly spaced, giving the correct support to the working platforms. i.e. avoiding overhanging boards etc. 9. Where the working platform is over 2 metres in height then guard rails and toe-boards (minimum 150 mm) must be fitted, and suitable access provided. There must also be an intermediate guardrails provided between the toe boards and the top guard rail. Guard rails may also be required at the inner side of the scaffold when erected around columns and piers. Erectors are required to wear full body harnesses during erection or demolition. Time of erection or demolition RED scaffold tag to be displayed. 10. Overhangs of working platforms must NOT exceed 4 times the thickness of the platform to prevent tipping. Otherwise it should be effectively secured. 11. Adequate façade and ledger bracing must be provided to the scaffold. 12. The scaffold maybe depending upon the situation or as advised by the Competent Person tied to the structure and supported with buttress rakers in order to ensure its stability. 13. Tools and materials are not to be left lying around on working platforms. 14. Materials are not to be tipped or dropped from heights. i.e. UNDER NO 15. Suitable access along the scaffold must be provided. CIRCUMSTANCES NO PEOPLE CLIMB THE OUTSIDE OF THE SCAFFOLD. 16. The working platforms must be secured to prevent dislodgement. Boards should not be less than 200mm wide and 50mm thick and should be close boarded. SCAFFOLDS CIRCUMSTANCES. MUST NOT BE OVERLOADED UNDER ANY 13 17. Scaffold structures must be inspected by a competent person every week and given green tag after any severe weather conditions which may affect the structures stability. Results of these inspections are to be recorded and signed by the competent person and notified to all those concerned. 18. Scaffold structure safety checks are to be recorded on GIL-MMS JV Scaffold Checklist and maintained as a record. The Jr. OHSE Manager will use these forms and ensure subcontractors are also implementing it. Any additional requirements by Clients regarding Scaffold inspections will also be followed as applicable. 19. Scaffold should be inspected on weekly basis with GIL-MMS JV Scaffold Checklist and signed green tag by the competent person. 20. GIL-MMS JV have introduced the “Safety Tags System” to indicate: If a scaffold has been partly erected or dismantled then a warning notice "SCAFFOLD INCOMPLETE & UNDER ERECTION - DANGEROUS and UNSAFE DO NOT USE” (RED Tag) must be affixed to the scaffold in an obvious position. For COMPLETED & SAFE Scaffold (GREEN Tag). The Competent person is to sign and write the date at the back of the appropriate tags. 3.6 Prefabricated Mobile Scaffold Towers The minimum base dimension of the tower determines the height of the tower. i.e. to the height of the working platform. For internal use the ratio of height to base is 3-1/2 times to 1. For external use the ratio of height to base is 3 times to 1. Towers must not be moved whilst persons are on the working platforms. When towers have been fitted with stabilizers because of the height to base ratio requirements, they will need to be dismantled before moving to a ratio 14 of 2-1/2 times to 1 to prevent overturning. Access should be by means of internal inclined ladders to the working platforms. 3.7 Training, Information, Instruction and Supervision Adequate training, information, instruction and supervision must be given and provided when Scaffold structures of any type are erected. Management must ensure they are satisfied that persons involved in the erection, dismantling and inspection of scaffold structures are competent to carry out the task. GIL-MMS JV recognises the importance and the need for the seriousness of working at heights and erection and dismantling of scaffolds, therefore in order to overcome this requirement GILMMS JV have arranged courses on competent person. Courses both for the GIL-MMS JV own staff and the Sub Contractors at costs. Weekly Safety Checklist of Access Scaffold Works Contractor/ Contractor Section Location Inspection Date (YY/MM/DD) No. 1 2 3 Items of Inspection Is the Red Tag/ Green Tag placed at scaffolding? Is the scaffold being erected under the direction of a competent person? Is the footing sound and rigid - not set on soft ground, frozen ground (that could melt), or resting on blocks? Inspection Time (YES) Status (NO) (N/A) Remarks 15 4 Has the erection site been evaluated for hazards such as earth fills, ditches, debris, underground electric wires, unguarded openings, or conditions created by other trades? Are wheels / castors locked for Mobile Scaffolding? Is the scaffold able to hold four times its maximum intended load? Are guardrails and toeboards in place on all open sides? Is the platform complete front to back and side to side (fully planked or decked, with no gaps greater than 1 inch)? Is the lumber free of cracks, splits, knots, or damage? Is the scaffold level? Have all compounds been inspected for defects such as broken welds, corroded members, and missing locks, bent or dented tubes? Are all braces, bearer, and clamps secured all sections pinned or appropriately secured? Is there a safe way to get on and off the scaffold, such as a ladder (without climbing on crossbraces)? Does the scaffold meet electrical safety clearance distances? Is the "X" bracing installed on the ends of the scaffold and every third set of post horizontally and every fourth vertical runner? 5 6 7 8 9 10 11 12 13 14 15 2/2 16 Are severe weather provisions in place i.e. during high winds, rain, snow, or bad weather? Have all planks been properly secured to the scaffold structure to prevent them blowing off in the event of high winds? Are the trained scaffold erectors available for erection and dismantle? 17 18 16 HEIGHT WORK PERMIT 19 GammonMosmetrostroy JV Where persons work under scaffold, is a 1/2 UAA-03 inch mesh screen provided between toe board and guard rail or has the area below the scaffold been cordoned off? When employees are working on suspended scaffolds, are lifelines firmly anchored to an overhead structure and not to the scaffold? Is the scaffold over 10 feet high, (if yes) is personal fall protection available, or are guardrails in place? Are guardrails available? Are toe-boards in placed and at least 150mm high? Are midrails or equivalent in place? Does the scaffold have a height to base ratio of at least 4:1? GAM/CMRL/SAFETY/15 Permit No – 20 21 22 23 24 25 Remarks : 1. This safety checklist shall be performed prior to installation or removal of scaffolding. 2. The status shall be recorded with: [ ] in "Yes" or "No" or "N/A" column. The required actions shall be indicated in rectification columns. 3. This checklist shall be signed by the GIL-MMS JV Senior / Site Engineer and filed by the safety personnel. GIL-MMS JV Senior / Site Engineer: ___________________ GIL-MMS JV Jr. OHSE MANAGER, ___________________ Subcontractor’s Representative: _______________ DURL Scaffold Competent Person: ___________ PERMIT TO WORK AT HEIGHT Location: ____________________________________________________________________ Description of work to be performed: ______________________________________________ Does other work in the area present a hazard to this job? ______________________________ Any change will invalidate this permit The copy of this permit shall be displayed at location of work as close to the work activity as practicable The validity of the permit is one shift only. SAFETY ASSURANCE CHECKLIST: Conditions of issue which must be observed at all time. Has proper access been provided at place of work, e.g. Ladder/steps? Have workers used all the PPE? 17 Have the workers worn full body safety Harness? Are lifelines (vertical / horizons) being provided? Have lifeline securely anchored & properly attached to the workers? Do workers have proper tools for the job? Do workers work on safe working platform? Item required and complied – (√) Have all person involved in the job being instructed on the safe & efficient method of doing the work? Has adequate illumination been provided? Is it barricaded below and provided with warning signs? Is anti-fall net practical or necessary to install? Others: Item required and not complied – (X) Not required – (NA) Permit completed by permit Holder ( Site supervisor/Site Engineer) I have read the sop relating to this work to be performed, I fully understand the nature of the work. Name: _________________________________ Position: _______________________ Signature: ______________________________ Date & Time: ____________________ Permit Issuer (Site Engineer/Chief Engineer/Station Manager) I have been ensured; the permit holder has observed and taken all the necessary safety precautions as stated in the sop and the checklist to prevent accident. The above work approved/not approved Name: Signature: Position: Date: Time: Cancellation of permit (Safety Engineer/Site Engineer/Chief Engineer/Station Manager) This permit to work is cancelled as SOP and safety checklist stated above not complied. Name: Date: Signature: Time: 4.0 Reference a. BOCW ACT 1996 b. OSHA 29 CFR Part -1926-501-502-503 c. BS-3913 Safety Nets d. BS-EN 131 Ladders e. BS-EN 361 Full body harness 18 f. BS-5062 Specification for self locking anchorages for industrial use. g. BS-5845 selection of the type of anchor. h. BS7171 Specification for mobile elevating working platfor. i. BS1139 Metal scaffolding. 19