Original Article

The Assessment of Heat Stress and Heat Strain in Pardis Petrochemical Complex, Tehran, Iran


Heat stress is well recognized among the hazardous physical agents that might be present during work. This study aims to compare WBGT index at acclimated and unacclimated people to permissible threshold limit value and study the differences between physiological parameters at them. Twenty one healthy men were participated in the study. All of the subjects were monitored in two different weather and working conditions: the Kar site (the work site) and the Paziresh site (the office site). A set of physiological and environmental parameters, namely heart rate, blood pressure, skin temperature and deep body temperature, dry temperature, wet natural temperatures, radiant temperature and relative humidity were measured and monitored simultaneously. The acclimated subjects were all of the ammonia-phase workers working in the hot-humid worksite. Other participants were selected from the work sites without risk of heat stress. Mean value of WBGT/TLV was less than one for the both acclimated and unacclimated groups at Paziresh site, while this value was more than one at Kar site and also mean of WBGT. For two groups, TWA / TLV were less than one during the working day. Mean physiological parameters were not significantly different between the acclimated and unacclimated subjects at both sites. However, physiological parameters such as heart rate and core body temperature showed statistically significant difference between two groups at Kar. Both groups of Paziresh were not exposed to heat stress, but Kar's operators continued work under conditions of heat stress.

Islam MZ. Influence of gender on heart rate and core temperature at critical WBGT for five clothing ensembles at three levels of metabolic rate [Thesis]. Florida: University of South Florida; 2005.

Occupational Safety and Health Administration (OSHA). Heat stress [OSHA Technical Manual (TED 01-00-015)]; 1999. [Cited 12 Feb 2013].Available from: URL: http://www.osha.gov/dts/osta/otm/otm_iii/otm_iii_4.html.

Lee SY, Brand JL. Effect of control over office workspace on perceptions of the work environment and work outcomes. J Environ Psychol 2005; 25: 323-333.

Parson KC. Environmental ergonomics: a review of principles methods and models. Appl Ergon 2000; 31:581-594.

Luecke CL. Gender difference during heat strain at critical WBGT [Dissertation]. Florida: University of South Florida; 2006.

Givoni B, R.F. Goldman RF. Predicting effects of heat acclimatization on heart rate and rectal temperature. J Appl Physiol 1972a; 35:875-879.

Givoni B, Goldman RF. Predicting heart rate response to work, environment, and clothing. J Appl Physiol 1973; 34:201-204.

Plog BA, Niland J, and Quinlan PJ. Fundamentals of Industrial Hygiene, 4th ed, National Safety Council, Itasca, IL, USA, 1996.

Givoni B, Goldman RF. Predicting rectal temperature response to work, environment, and clothing. J Appl Physiol 1972b;32:812-822.

International Labor Organization (ILO). Encyclopedia of occupational health and safety. vol. 2, 3rd ed. ILO, Geneva, Switzerland, 1983.

Minard D, Goldsmith R, Farrier PH, Lambiotte BJ. Physiological evaluation of industrial heat stress. Am Ind Hyg Assoc J 1971; 32:17-28.

World Health Organization (WHO). Health factor involved in working under condition of heat stress, Technical report series 412.WHO, Geneva, Switzerland, 1969.

Wyndham CH. Change in central circulation and body fluid and blood space during acclimatization. J Appl Physiol 1968; 25:586-593.

Chen ML, Chen CJ, Yeh WY, Huang JW, Mao IF. Heat stress evaluation and worker fatigue in a steel plant. J Occup Environ Hyg 2003; 64(3):352-359.

Logan PW, Bernard TE. Heat stress and strain in an aluminum smelter. J Occup Environ Hyg 1999; 60(5):659-665.

National Institute for Occupational Safety and Health (NIOSH). Criteria for recommended standard: Occupational exposure to hot environments. NIOSH, Publication No. 86-113, USA, 1986.

International Organization for Standardization (ISO).Hot environments -- Estimation of the heat stress on working man, based on the WBGT-index (ISO 7243) [Standard], 1989.

International Organization for Standardization (ISO).Ergonomics of the thermal environment -- determination of metabolic heat production (ISO 8996) [Standard], 2001.

Occupational Safety and Health Administration (OSHA). Heat stress guide. Minnesota Department of Labor and Industry, Minnesota, USA, 2012.

American Conference of Governmental Industrial Hygienists (ACGIH). Threshold Limit Value and Biological Exposure Indices. ACGIH, USA, 1995.

International Organization for Standardization (ISO).Ergonomics of the thermal environment -- Analytical determination and interpretation of heat stress using calculation of the predicted heat strain (ISO 7933) [Standard], 2004.

American Conference of Governmental Industrial Hygienists (ACGIH). Threshold Limit Value and Biological Exposure Indices. ACGIH, USA, 2001.

Avellini BA, Kamon E, Krajewski JT. Physiological responses of physically fit men and women to acclimation to humid heat. J Appl Physiol 1980; 49(2): 254–261.

Frye AJ, Kamon E. Responses to dry heat of men and women withsimilar aerobic capacities. J Appl Physiol 1981; 50:65–70.

Keatisuwan W, Tadakatsu O, Tochihara Y. Physiological responses of men and women during exercise in hot environments with equivalent WBGT. J Physiol Anthropol Appl Hum Sci 1996; 15:249–258.

McLellan TM. Sex-related differences in thermoregulatory responses while wearing protective clothing European. Eur J Appl Physiol Occup Physiol 1998; 78(1): 28–37.

Moran DS, ShapiroY, Laor A, Izraeli S, Pandolf, KB. Can genderdifferences during exercise-heat stress be assessed by the physiological strain index? Am J Physiol 1999, 276(6 Pt 2): R1798–R1804.

Morimoto T, SlabochovaZ, Naman RK, Sargent II, F. Sex differences in physiological reactions to thermal stress. J Appl Physiol 1967; 22(3): 526–532.

Paolone AM, Wells CL, Kelly GT. Sexual variations inthermoregulation during heat stress. Aviat Space Envir Md 1977; 49:715–719.

Sawka MN, Toner MM, Francesconi RP, Pandolf KB. Hypohydration and exercise: effects of heat acclimation, gender, and environment. J Appl Physiol 1983; 55(4): 1147–1153.

IssueVol 5 No 1 (2013) QRcode
SectionOriginal Article(s)
Heat stress Heat strain WBGT Physiological parameters

Rights and permissions
Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
How to Cite
GOLBABAEI F, MONAZZAM M, HEMATJO R, HOSSEINI M, FAHANG-DEHGHAN S. The Assessment of Heat Stress and Heat Strain in Pardis Petrochemical Complex, Tehran, Iran. Int J Occup Hyg. 2015;5(1):6-11.