Tibbi-i-kar

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Background: Exposure to high temperatures is common among workers in warm environments (especially in bakeries) which could cause some undesirable physiological effects. The aim of this study was to determine heat stress and its relationship with physiological parameter of sublingual temperature in workers employed in bakeries of Arak city. Methods: In this cross- sectional study, 126 workers employed in 63 bakeries in Arak was evaluated. Heat stress was evaluated based on WBGT (wet bulb globe temperature) index and physiological strain was evaluated based on sublingual temperature. The heat stress was measured using digital WBGT apparatus in workstations of the bakers and the bread dough co-bakers as the hottest places. Sublingual temperature of workers was measured using electronic sublingual thermometer. Data was analyzed using SPSS version 16 software. Results: In 76% of cases, heat stress exposed to workers based on WBGT index, was more than national recommended limit. Moreover, in 48% of cases, heat strain of workers based on sublingual temperature index was also more than the national recommended limit. The results showed significant difference between WBGT index in the bakeries based on baking technology type (traditional and mechanized bakeries) (p<0.001). The results showed significant difference between sublingual temperatures of workers in the bakeries based on baking technology type (p<0.001). Conclusions: Mechanization of bakeries could make notable effects on reducing the heat strain of workers. The significant relationship between WBGT index and sublingual temperatures of workers confirmed the reliability and generality of WBGT index for evaluating heat stress in bakeries.

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Introduction: Protective clothes are among the basic needs of firefighters against their occupational risks. Combination of heat stress effects caused by muscle activation and protective clothing, result in a high level of strain in the regulating system of body temperature. The aim of this study was to evaluate the practical cooling method of hand and forearm immersion in water.

Methods: In this study, fourteen professional firefighters were assessed. Each fire fighter wore protective clothing and heart rate, core body temprature and skin temprature were measured in sitting position. Then each subject walked on a treadmill in two 20-min bouts (5 km/h, 7.5% gradient) separated by a 15-min recovery period, during which firefighters were cooled (case) via application of hand and forearm water immersion and remained seated without cooling (control). During exercise and recovery time, firefighters, physiologic parameters (heart rate, core body temperature and mean skin temperature) were measured and recorded every five minutes.

Results: The results of marginally modeling of longitudinal responses using generalized estimating equations method showed that paremeters of heart strain (core body temprature, skin temprature and heart rate) were significantly reduced after intervention (p<0.05).

Conclusion: In situations that intense fire actions must be faced, the cooling strategy of dipping hands and forearms in water could be considered as an effective and simple method in comparison to other cooling strategies.

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Introduction: Water and electrolytes are essential to maintain the health and performance in hot occupational environments. The aim of this study was to determine the effect of different drinks on indices HSSI, PESI and PSI under laboratory conditions.

Methods: This clinical trial study was conducted on 13 male students in hot and dry laboratory conditions, (40 ° C, humidity 30%). In 3 steps within 2 hours of interferences, water, the combination of water and lemon, and lemon juice in the amount of 400 cc for 4 times was given to the participants. Every 10 minutes from the beginning of exposure to the heat index, Heat Strain Score Index (HSSI), Perceptual Strain Index (PESI), Physiological Strain Index (PSI), heart rate and oral temperature were measured. Analysis of variance with repeated observations and post hoc test was used to analyze the data.

Results: The results showed that the index of HSSI (P= <0.001), PESI (P=0.001) and PSI (P = <0.001) has had a significant difference when using 3 interferences.

Conclusion: Drinking leads to keeping and maintaining normal conditions in participants. Compared with water and the combination of water and lemon, lemon juice drink has the greatest impact in reducing the average scores in all three indicators.