ASSOCIATION BETWEEN THERMAL COMFORT AND WORK-RELATED SYMPTOMS IN LOW ENERGY OFFICE (LEO) BUILDINGS, PUTRAJAYAMohd Nafiz Bin Shaharon Department of Community Health, Faculty of Medicine and Health Sciences Universiti Putra Malaysia E-mail: [email protected] Tel: +603 - 89472424; Fax: +603 - 89450151 Juliana Jalaludin Department of Community Health, Faculty of Medicine and Health Sciences Universiti Putra Malaysia E-mail: [email protected] Tel: +603 - 89472424; Fax: +603 - 89450151 Abstract The issues of workers comfort and workspace quality in office buildings have gained an important concerned from the Ministry of Energy, Water and Green Technology, Malaysia. New energy efficient building concepts and technologies require a revision of comfort standards, to create suitable thermal condition in avoiding occupants’ dissatisfaction, adverse effect on their productivity and overall building performance. A quantitative assessment was conducted in a Low Energy Office (LEO) building, in Putrajaya using Babuc-A (Portable air quality monitor) and a qualitative assessment using set of questionnaire adapted from ASHRAE Standard (2004) and IEQ survey questionnaire. Total of 99 respondents were chosen using a stratified random sampling and based on the worker preferences the results showed that sinusitis (x2=7.50, p<0.05), eczema (x2=8.60, p<0.05) and fatigue (x2=10.24, p<0.05) was reported for the last four weeks and stuffy nose (x2=8.59, p<0.05) was a current reported symptoms on the studied day. However, statistical study showed no significant association between work-related symptoms and PMV for LEO building suggesting that the current thermal environment did not causing the work-related symptoms in the office. The thermal comfort zone for this building was in the temperature range of 21.6oC to 23.6oC and relative humidity of between 42 to 54 percent. The results suggested the thermal condition was in the acceptable range of ISO 7730 (calculation of PMV and PPD) and that a lower room temperature was preferred by Malaysian in office environment compared with the temperature criteria cited in ASHRAE Standard-55. Keywords: Thermal comfort, Satisfaction, Low Energy Office, Natural ventilation, PMV . 1 Thermal comfort was measured by the number of employees complaining of thermal discomfort (HSE. The occurrence of symptoms increased much more with raised indoor temperatures in the winter than in the summer due to the larger difference created between indoor and outdoor temperatures. radiant temperature. (2005). dry bulb temperature. Work. al. Work. 1996) The US EPA base study found that higher indoor temperatures. Work related symptoms in office works were divided into three categories which are i. increased worker symptoms (Mandell. INTRODUCTION Thermal comfort was defined in British Standard BS EN ISO 7730 as (ISO 7730): ‘that condition of mind which expresses satisfaction with the thermal environment. and AirConditioning Engineers (ASHRAE) as that state of mind which expresses satisfaction with the thermal environment (ASHRAE. nasal breathing. Refrigeration. nasal discharge (may change from clear to white to green).related musculoskeletal symptoms iii. chest tightness. ventilating and airconditioning (HVAC) system. though it is difficult to satisfy everyone in a space due to physiological and psychological variation from person to person (Nazanin. even within the recommended thermal comfort range. Thermal comfort is one of the most significant factors affecting environmental satisfaction. 2 . high fever..related skin symptoms Work-related respiratory symptoms refer to any symptoms that include the effects on the lower and upper respiratory tracts. 2008). and sore or scratchy throat. 2009).’ (Sieber et. there are seven major factors which are. al.related respiratory symptoms ii. 2008). clothing and the length of time exposure (Sherman. air velocity. Work. water vapor pressure. Examples of work related symptoms for lower respiratory are shortness of breath. and also improving when away from the building. 1984). metabolic rate. coughing and fatigue whereas for upper respiratory symptoms. 2005).. the examples are runny nose (rhinorrhea). Work-related illness on the other hand was defined as ‘symptoms experienced at work at least one day per week during the last four weeks. virtually all the heating. sneezing. According to Chen et.’ Thermal comfort was defined by American Society of Heating. tendons. ligaments. 2002). Work-related musculoskeletal symptoms occur when mechanical workload is higher than physical capacity of human body.related skin symptoms are easy to recognize by referring to the apparent of symptoms on the skin on an building occupants especially under regular exposure. 3 . al. 2008) Overall this study on thermal comfort were emphasizing the importance of thermal comfort for office occupants and highlight that achieving thermal comfort in offices not only delivers more satisfaction for the occupants. and atopic dermatitis (eczema) (O’Malley . Furthermore. joints.related musculoskeletal symptoms on the other hand refers to symptoms such as muscle. A results of a study in Germany. the measured the factors contributing to thermal comfort more accurately. 1988). 2008). The Predicted Mean Vote (PMV) and Percentage People Dissatisfied (PPD) index and use of BS EN ISO 7730 and BS EN ISO 10551 British standards are recommended (HSE. To enabling a researcher to improve the thermal comfort in the workplace. An estimation of thermal comfort can be calculated when the six parameters are measured or estimated. nerves. al. are capable of causing different types of occupational skin disease such as contact dermatitis (both allergic and irritant). a survey conducted on workplace occupant satisfaction in 16 office buildings in Germany revealed that the occupants’ control of the indoor climate and moreover the perceived effect of their intervention strongly influences their satisfaction with thermal indoor quality (Wagner et... high relative humidity and very overcast cloud cover (Dahlan. Naturally ventilated building designs can perform efficiently in hot climate countries like Malaysia because of their low evaporation rate. contact urticaria. long hours of sunshine.Work. Frequent changes in arrangement in office space and the huge amount of the cables brought about by the extensive use of computers make the implementation of air conditioning office a necessity (Wan et. Fanger’s comfort model was based on Predicted Mean Vote (PMV) and Predicted Percentage Dissatisfied people (PPD) (Nazanin. the ‘feeling comfortable’ was very subjective in nature and cannot be defined objectively. buildings are designed to enable natural ventilation. but also improves their performance (Nazanin. 2008). 2008). cartilage and blood vessels are chronic overuse and misuse. This is a chronic occupational illness as a result of repeated trauma rather than happening through a single accident or injury (Washington State Department of Labor and Industries 2007) Work. 2007). As a country that is progressing towards an energy consumption conscious target. .1 meter (Daghigh et. ill-conditioned one (Sherman. Green Technology and Water. an occupants’ response to (and hence sensation of) the environment will be a strong function of his/her physical condition. shivering. Sampling Methods Numbers of 99 respondents. 1985).g. 2009) above the floor. a young. which are the staffs in the Ministry of Energy. sweating. relative humidity. healthy body recovers more quickly and therefore can respond to changes in thermal stress more quickly than can an older. Because the human body has its own temperature regulating responses (e.. Physical measurements were taken at the height of 1. etc. 2. including both male and female within the age of 20-40 years old (young adults). al. radiant temperature and air velocity (Wagner et.2. Green Technology and Water.. having normal BMI and currently in healthy status and doing desk-based job (Natasha et.). Malaysia. 2009). al. Malaysia. Two types of approach were conducted in collecting the data which are the physical quantities instruments and workers’ satisfaction survey.3.METHODOLOGY 2. The sample was recorded in 4 . This approach involves the use of mechanical devices in collecting data. were selected based on the location with the high numbers of workers located to be involved in the survey. Four environmental parameters were measured using physical quantities instruments (Babuc A) which were dry bulb temperature. vasodilatation/ constriction. Location The location of this study was conducted in a Low Energy Office (LEO) Building. Selection of Respondents The populations involved in this study were selected using a stratified random sampling where numbers of respondents at each location depends on total occupants during the time of the studied and were estimated that 80% of all workers at each locations were. This LEO building is the first government building of its kind to be built with integrated energy efficient design. 2007). al. Respondents were selected based on the inclusion criteria which are workers in each location worked inside a low and high-occupancy larger open plan rooms in the building. 2. which represents the height of the occupant at seated level. Physical quantities instruments Physical quantities instruments was an objective approach in data collection.. own by the Ministry of Energy.1. It can be connected to a PC where the measurements can be filed and re-processed with LSI programs. dwelling. and iv. the frequency and the time of the thermal-comfort problem as well as the general conditions of the thermal environment can greatly help in defining the pattern of complaints and distribution in terms of time and space (Budaiwi.2 met which are sedentary activities (office. 2007).0. Compliance with ASHRAE 55 (2004) and ISO 7730 (2005). Berkeley.15.6 and Microsoft Excel v. 5 .2. metabolic rate and clothing insulation were estimated in accordance with ISO 7730 and ASHRAE Standard-55. Analysis for this researched was divided into four sections: i. A questionnaire survey that is simple and designed to seek occupant input for the level. and laboratory) and the Clo.4. Data analysis All the physical measurements of the environment under studied were analyzed using InfoGap v. 2. In this study.every 30 seconds interval for one hour.87. Comparison between questionnaire and physical measurement. Having measured the environmental parameters. Workers’ satisfaction survey Subjective thermal comfort data were recorded using a questionnaire adapted from ASHRAE Standard (2004) and also a mixture of the indoor environmental quality (IEQ) survey questionnaire from the Centre of Built Environment (CBE) at the University of California. school.values were calculated to be 0. Results from the physical measurements iii. Results of the questionnaire survey ii. the metabolic rate was set to be 1.2007 whereas data from surveyed was analyzed using Statistical package for Social Science (SPSS) ver. 92 22.71 15.63◦C.03 21.58 15.006 0.67 15.36 23. wet bulb.16 48.01 21.60 21.57 22.15 23.04 22.07 0.81 53.76 49.89 0.11 23.68 21.89 22.92 44.30 22.90 21.10 22.013 0.70 21.09 42.63 15.41 15.52 22.14 22.65 21.012 0.38 53.17 21.63 47.13 22.81 23. The air temperature recorded in the measurement range between 23.18 44.67 20.4.61◦C as the highest reading to the lowest of 21.11 21.45 22.96 21. relative humidity and air velocity as the main parameters needed in calculating the thermal comforts PMV and PPD values.20 23.28 21.18 14.24 * MRT = Mean Radiant Temperature + 6 . 3.026 22.: Result of indoor thermal measurement TeAIR (°C) TeWET BULB (°C) TeDRY BULB (°C) TeGLOBE (°C) Rel HUM (%) AIRVel (m/s) *MRT .62 21.022 0.80 22.79 22.019 0.98 21.1.59 21.95 22.75 21.41 21.33 21.02 22.83 15.018 0.021 0. the parameters measured were dry bulb.82 22.76 21.61 21.01 20.41 53. (°C) Floor 1 Floor 2 Floor 3 Floor 4 Floor 5 Point 1 Point 2 Point 3 Point 1 Point 2 Point 3 Point 1 Point 2 Point 3 Point 1 Point 2 Point 3 Point 1 Point 2 Point 3 23.35 49. Based on the table.59 20.73 22.43 15. RESULT Instrument Results There are five days of where the measurement was took it place and in each day.31 42.68 22.58 14.010 0.10 22.024 0. The radiant temperature inside this table was calculated based on the given equation by Mc Quiston (2005): = + ( ) Table 3.03 0.38 14.34 22.07 15.61 15.36 21.015 0.11 22.30 14.95 21.1.44 22. globe temperature.79 49.80 21.87 22.18 47.52 23.49 22.011 0. The results of indoor temperatures during the study period were given in Table 3.01 54.34 21.025 0.16 22.75 22. three sampling points was selected which ends up to be 15 sampling points for this total study.96 42.46 14.89 23.76 15.3. 2 21. PPD is the predicted percent of dissatisfied people at each PMV.0 5.0 22. Tg = globe temperature.8 23. PMV and PPD values PMV PPD Locations Operative Temperature (°C) 0.0 5.8 23.10 Point 3 0.0 22. m/s. Several comfort indices. Ta = ambient air temperature.2 were done by using a software program named PMVcalc version 2. Laboratory of Ventilation and Air Quality University of Gävle as well as Microsoft Excel (Figure 3.9 23.2 5.3 6.55 FLOOR 2 Point 2 -0.90 Point 3 0.2 5.85 Point 1 FLOOR 5 Point 2 -0. and C = 0.0 5. The PMV index predicts the mean response of a large group of people exposed to a certain environment following 7-point thermal sensation scale according to the ASHRAE. PPD increase. Table 3.2 5.45 The calculation of PMV and PPD in Table 3. PMV is derived from the physics of heat transfer combined with an empirical fit to sensation.0 22.1 5.2 5.00 Point 1 0.8 23. K.85 Point 3 0.0 5.2 5.8 22.2 21.1 5.2 5.50 Point 3 -0. K.8 21.00 Point 3 -0. V = air velocity.2 21. These indices attempt to correlate human thermal comfort with environmental conditions.0.Where: Tmrt = mean radiant temperature.6 Point 1 0. K.95 Point 1 0. which was modified by Håkan Nilsson from the Department of Technology and Built Environment.2: Results of calculated operative temperature.1 5. PMV establishes a thermal strain based on steady-state heat transfer between the body and the environment and assigns a comfort vote to that amount of strain.35 FLOOR 1 Point 2 0. As PMV changes away from zero in either the positive or negative direction.2 21. such as PMV and PPD have been developed.247 x 109: Human thermal comfort is influenced by psychological as well as physiological factors.35 Point 1 FLOOR 3 Point 2 0. PMV and PPD were calculated based on combination results of physical measurement and observation of type of activity and clothing. 7 .25 0.1).05 FLOOR 4 Point 2 0.8 22.0 22.1 5. 053 Itchy/ rashes 4 (4.3: Association between past reported work-related symptoms and thermal preference 4 weeks ago Symptoms x2-Value p-Value Yes (%) No (%) Dry eye 15 (15.874 Sore throat 3 (3.0) 0.9) 10.0) 0.0) 96 (97.8) 0.006 8 .05).8) 0.271 0.874 Fatigue 13 (13.7) 8.200 0.0) 95 (96.886 Fever like symptom 32 (32. A Chi-square test of the association between the past reported symptoms with workers’ thermal preference was conducted and the resulted with only fatigue shows significant association with thermal acceptability (x2 = 10.6) 2.873 Stuffy nose 35 (35.882 0.0) 0.2) 80 (80.0) 95 (96.241 0. Health Status Table 3.310 Watery nose 4 (4.24.1: PPD as a function of PMV (ISO 7730) for each locations 3. p < 0. Table 3.4) 64 (64.241 *0.2.1) 86 (86.3 showed the reported symptoms of work-related illness within one month period.345 0.2) 84 (84.3) 67 (67.Figure 3.905 Headache 19 (19.269 0.269 0. 8) 3. p < 0.582 * Significant values having the symptoms Table 3. Table 3.170 Sinusitis 23 (23.542 0.057 0.6) 16.8) 17. From the table.606 *0.2) 82 (82.762 0.4 showed the history of disease among respondents of the.522 0.952 0.1) 91 (91.152 Fatigue 13 (13.9) 1. The outcome of the test showed that there are no any significant association between PMV and work-related symptoms of respondents in LEO’s Building.6) 18.2) 76 (76.645 Sore throat 3 (3.8) 14.8) 13.889 * Significant values having the symptoms Table 3.263 Shortness of breath 17 (17.7) 12.5.8) 0.3) 67 (67.231 0.0) 95 (96.05) shows the significant result of having the association with the thermal acceptability in the building.325 0.0) 8.4) 64 (64.0) 95 (96.992 0.50.0) 11.876 0.413 Stuffy nose 35 (35.2) 77 (77.0) 19.954 0.0) 96 (97.083 0.1) 86 (86.0) 97 (98.5: Association between PMV and reported work-related symptoms On same Day Symptoms x2 -Value p-Value Yes (%) No (%) Dry eye 15 (15.0) 11.504 *0. sinusitis (x2 = 7.6) 0.023 Eczema 2 (2.8) 7.2) 82 (82. Table 3. Putrajaya.165 Watery nose 4 (4.453 * Significant values having the symptoms 9 .683 Shortness of breath 17 (17.Dry Skin 42 (42.60.239 Fever like symptom 32 (32.05) and eczema (x2 = 8.2) 80 (80.014 Smoking 8 (8.522 Dry Skin 42 (42. p < 0.236 0.588 Itchy/ rashes 4 (4.610 Headache 19 (19.4) 57 (57.504 0.360 0.4: Association between history of disease and thermal preference Disease History Yes (%) No (%) x2-Value p-Value Asthma 22 (22.2) 84 (84.4) 57 (57. showed the result from Chi-square test of the association between the the thermal comfort PMV (predicted mean votes) and reported of work-related symptoms by the respondent of the studied.9) 13. 3. most of which range from 1 (Slightly cool) to 1 (slightly warm).2: Thermal Sensation Votes (TSV) results A 7-points humidity sensation namely called ‘Humidity Perception Vote (HPV)’ (-3 very dry. 10 . 1 slightly humid. ASHRAE Thermal Sensation Scale.3. Malaysia did not exceed the humidity level of between 40-60% provided by the Department of Occupational. 2 humid. -2 dry.6% of the respondents perceive thermal sensation as neutral. Thermal Response Vote Figure 3. It indicates that most of the occupants adjusted to the climatic variation and remained satisfied with the indoor thermal environment. 0 just right. -1. in the Guidelines on Occupational Safety and Health in the Office handbook. The humidity level inside this LEO building owned by the Ministry of Energy.slightly dry.2 showed the distribution of thermal sensation votes. Figure 3. 3 very humid) similar to the ASHRAE standard 55. Green Technology and Water. Safety and Health (DOSH) Malaysia. and 63. 4. a zero votes means that the respondents felt that the air velocity was just right. Thermal Preference 11 .Figure 3. Figure 3.3: Indoor Humidity Perception Votes (HPV) Figure 3.4: Indoor Draft Perception Votes (DPV) 3.4 showed the Indoor draft perception vote (DVP) results with a vote of -3 indicates the air velocity level in the building was too low or motionless. A small portion of 4% out of all respondents in this study perceived that the air was to steady or motionless while a large portion of 96% of respondents accepted the air velocity was just right with all the votes centered between -1 to 1. This studied showed.0%) 24 (24.2%) 54 (54. Value of -2 indicate the humidity level to be drier and 2 indicates the humidity level to be more humid and for air velocity.Thermal preference votes indicate what the respondents preferred to be having in their working office environment.1% Neutral 48.1% stated their positively dissatisfied and 48.7%) 3.5%) 28 (28.6%) 39 (39. the thermal sensation scale of -2 indicate more air movement preferred and 2 more less air movement preferred by the studied respondents. out of all the respondents.4% Figure 3. Table 3. only 40.5 showed the satisfaction level of all the respondents in LEO building towards the indoor temperature.5% considered the condition inside the building was just right.5.5% Satisfied 40.6: Association of thermal sensation and preference responses Thermal preference Thermal sensation scale parameters -2 -1 0 1 2 Air temperature 0 17 (17.6 showed the association between the thermal sensation and the preference responses from the respondents of the study.2%) 69 (69. Dissatisfied 11.4%) 0 2 (2%) 0 Air velocity 4 (4. Table 3.5: Occupants perceived general satisfaction with the indoor temperature 12 . 11. and also to compare the results studied with the ASHRAE Standard 55 thermal comfort condition (80% or more of the occupants are satisfied with the temperature). the thermal sensation scale indicates the value of -2 as more warmer preferred to the value of 2 as more cool preferred by the respondents.3%) 0 Relative humidity 0 3 (3%) 57 (57. For the indoor air temperature.4% were positively satisfied with the condition. Occupants’ Perceived Thermal Satisfaction Figure 3. This statement was proved by Sherman (1985).31 *0. Ninety-nine respondents out off the whole building occupants were selected for this study with the portion of male workers towards female workers was 20.7 showed the statistical results in determining the association between perceived thermal comfort that was votes by respondents and the calculated PMV values based on measured temperature in LEO’s Building. 83. the acceptability and the perception towards the working environments would be different although they were exposed to the same contributing factors.8% of the respondents were aged between early 20 to 30 years old. 4.7: Association between perceived thermal comfort and calculated PMV Perceived Thermal comfort Thermal sensation Humidity perception Velocity perception Occupants’ satisfaction x -Value p-Value 82.001 134.8%. al. According to previous study by Daghigh et. The selection of respondents was conducted randomly based on work location of the workers who did the clerical and secretarial task in an open arrangement working area.36 *0. the selection of open arrangement area would make the occupants in the area to having the same thermal condition as compared if an occupant working in a closed area (room) because the level of velocity. From this percentage it shows that the majority the studied respondents were at young aged during the study was conducted. and 15. It has been said that human in a group of early adulthood can adapt faster to the thermal environment compared to those who were at already in the late stage of adulthood. The reason was that when the population in a certain location was high.001 130. The other 1% aged above 30 years old.001 2 4.2% to 79. selection of respondents is important. temperature and humidity level between places are different.1. DISCUSSION Socio Demographic For the purpose of the study. (2009). 13 . Table 3.2% aged between 30 to 50 years old. From the survey. This proved that the perceived thermal comfort parameters can influence the workers’ satisfaction in LEO building.31 *0.• Table 3. Association Between Perceived Thermal Comforts with Perceived Occupants’ Satisfaction Due to the location of this country which is close to the earth equator. only sinusitis (x2 = 7.05) seem to have the correlation with the thermal acceptability among the LEO building occupants In determining the study hypothesis for this study that there is a significant association between thermal comfort (calculated PMV) and work related symptoms. sinusitis.05.606.241. such as air temperature. Association between these ten listed work-related symptoms towards the LEO building occupants’ thermal preference. may also contribute to the symptoms of sick building syndrome (HSE 2008). The mean temperature is approximately 27◦C. (Sieber et. 4. It showed that the out of four.4. Part two of the health related questions inside the questionnaire form asked about the respondents’ health history if whether or not they had ever experiencing any health problems related to asthma. The first part is the general health symptoms related to health problems. humidity and air movement.05) and eczema (x2 = 8.05). radiant heat. The result of the first listed group of current symptoms shows that the respondents reported to have suffered from fatigue (x2 = 10. This however was supported by HSE (2008).symptoms have no significant at all with the PMV values of thermal comfort in the LEO’s building. Based on the results obtained from the test.3. it was found that all the ten listed work related. eczema and the habit of smoking. which suggested that workrelated symptoms were not only influenced by temperature but also the condition of Indoor Air Quality (IAQ) of the building.35◦C all over the year. and also improving when away from the building. p < 0. productivity may fall and in some cases people may refuse to work in a particular environment. In some aspects of the thermal environment. employee complaints may increase.. the association was determined using Chi-square test. the temperature range is between 25◦C . Association Between Thermal Comfort (PMV) and Work-Related Symptoms Work-related illness was described as medical symptoms experienced at work at least one day per week during the last four weeks. From the results of the votes for these four parameters. a Chisquare test was used to determine the degree of relationship between the two variable with the significant value of p <0. was not cause by indoor temperature. the 14 . al. Due to thermal discomfort. p < 0. The results also have suggested that that the reported work-related symptoms from the building occupants. the same nonparametric test namely Chi-square was used.504. the question related to health was divided into two parts. Symptoms experiencing by the building occupants could be cause by some others factors such as indoor pollutants. p < 0.2. In the studied survey. 1996)). 1. the occupants must be viewed as important contributors throughout the assessment process as they are the source complaints and a potential source of useful information that can help in assessing the extent of the problem and identifying solutions (Budaiwi. The calculation of PMV and PPD using Fanger’s equation shows that the current condition of LEO building was in the comfort range based on ISO 7730. Therefore it appears that the occupant’s perceived satisfaction with the temperature is not in compliance with the acceptable thermal satisfaction range within ASHRAE Standard 55 (80% or more of the occupants are satisfied with the temperature).. 15 .. Compliance with ASHRAE Standard-55 and ISO 7730 The calculated psychometric chart for the LEO office building studied was shown in figure 4. al. it shows that all the perceived thermal comfort parameters which are thermal sensation votes (TSV). This shows that with taking into accounts the measurement temperature. In determining the association between the perceived thermal comforts with perceived occupants’ satisfaction using a statistical test.4% of the respondent satisfied with the current condition and another 48.4. a chi-square test was used. Thermal comfort is one of the most significant factors affecting the occupants’ environmental satisfaction (Croome et. it shows that none of the studied samples were in compliance with the Standard. indoor humidity perception votes (HPV) and draft perception votes (DPV) shows significant association with the occupants ‘ perceived thermal comfort votes with the p-value <0. 2009). al.. In the effort of knowing the indoor thermal problems inside the LEO building. From the figure below.5% out of all respondents felt that the condition in the building was just right. 2000). the degree of occupants comfort level can be determined and comply with the standard.relatively humidity level can raised exceeding 80% (Ismail et. This result shows that the building occupants felt that the current outdoor temperature was too high which they had to decrease the indoor temperature to achieve comfortability. However. Form the test. 2007). The studied in LEO building shows that 40. along with the bounds of the ASHRAE Standard 55 comfort zone range.1% of the respondents felt dissatisfied with current condition in the building. The 11. All the fifteen sampling location shows the compliance with having the temperature within range provided by the ISO 7730. the temperature was a bit lower than the recommended temperature of between 23◦C to 36◦C for the air conditioning office. 2004).001 4. though it is difficult to satisfy everyone in a space due to biological variation and perception from person to person (ASHRAE. metabolic rates and clothing insulation. The entire location sample studied resulted within the acceptable range of relative humidity which was between 30% to 60%. Putrajaya. The calculated values of Predicted Mean Votes (PMV) and Percentage People Dissatisfied (PPD) of measured temperature in Low Energy Office building in Putrajaya comply with ISO 7730 Standard 2005 with the percentage of PPD did not exceed 10% of all studied respondents. which suggested that work-related symptoms were not only influenced by temperature but also the condition of Indoor Air Quality (IAQ) of the building. However. there is a positive relationship between measured thermal indoor temperatures with workers satisfaction in LEO building. but all the measured indoor temperature in Low Energy Office building in Putrajaya did fall within ASHRAE Standard-55 thermal comfort zone. CONCLUSION The results of this study were used to test the hypothesis with the result that there are no significant relationship between the work-related symptoms and thermal environment in the LEO’s Building. RECOMMENDATION 16 .Psychometric Chart RH = 60% RH = 30% Figure 4. The results also suggested that the reported work-related symptoms from the building occupants. 6. was not cause by indoor temperature.1: A comparison of average monitored data from all points in the buildings with ASHRAE Standard 5 5. This was supported by HSE (2008). 17 . or too low. more study need to be conducts to prove that indoor temperature can have a significant effect to acute and chronic health symptoms. Since research regarding association between thermal comfort and health are limited. it is difficult to satisfy everyone within the same thermal environment. so ventilation must be adequate for each person at a minimum rate of 10 liters fresh air per second per person for general office space or 10 liters fresh air per second for every 10 square meters of floor space is recommended. If the level of humidity is too high. 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