Self-assessed threshold for cold temperatures and thermal insulation of clothing among poultry workers.

The association between self-assessed cold threshold (CT) and thermal insulation of clothing (Icl) was analysed in 283 poultry workers in Thailand. The mean CT was 13.5 °C (range - 28-29) and the mean Icl was 1.23 clo (range 0.35-2.21). The adjusted CT remained unchanged at low Icls (0.35 through 1.25 clo) but was estimated to increase by 14.8 °C at high Icls (1.25 through 2.21 clo). Overall, CT was higher by 2.4 °C (95% confidence interval [CI] 0.3-3.8) at high (≥ 1.25 clo) than that at low (< 1.25 clo) Icl, but this difference was modified by personal and work-related factors. The difference was 2.6 °C (CI 0.5-4.6) for older (30-57 y) compared to younger (18-29 y) participants, with an excess of 7.3 °C (CI 5.6-9.0) for low vs high educated participants, 2.6 °C (CI 0.5-4.8) for those doing heavy vs light work, 7.4 °C (CI 3.7-11.0) for alcohol consumers vs others, and 3.4 °C (CI 0.6-6.3) for smokers vs non-smokers. The differences were independent of personal characteristics and worksite physical conditions and were interpreted as increased cold sensitivity among subgroups with lesser stamina and poorer health. Sensitive worker subgroups should be identified, and their need for cold protection should be reviewed.

Cold-related pain in the face, upper limbs, and lower body among Thai chicken industry workers: a cross-sectional study.

OBJECTIVE: There is limited information on cold-related pain (CRP) in various parts of the body among workers employed in cold environments. We, therefore, determined the prevalence of CRP among Thai chicken industry workers and attempted to identify vulnerable subgroups. METHODS: Four hundred and twenty-two workers in four chicken meat factories in Thailand were asked about CRP in the face, upper limbs, and lower body. The results were expressed as adjusted prevalence and prevalence differences [PD; in percentage points (pp)] and their 95% confidence intervals (CI). RESULTS: Overall, 80% of the subjects suffered from CRP in at least one site on the body: 66% in the upper limbs, 65% in the lower body, and 44% in the face. In most sites, CRP increased from the lowest to the highest educational level, notably in the nose with a PD of 36 pp [95% CI 23, 49]. Forklift drivers experienced knee pain [PD 21 pp (0, 41)], and manufacturing [PD 27 pp (15, 38)] and storage workers [PD 24 pp (10, 37)] experienced thigh pain more often than office workers, while office workers reported CRP in the cheeks, ears, wrists, and fingers more often than other workers. Women had more CRP than men in several body sites. CONCLUSIONS: The majority of workers suffered from CRP. Intensified protective measures should be targeted not only for forklift drivers and storage and manufacturing workers, but also for the highly educated as well as the office staff who showed excessive prevalence of CRP in several body sites.

Cold-related symptoms and performance degradation among Thai poultry industry workers with reference to vulnerable groups: a cross-sectional study.

BACKGROUND: Few studies have examined cold-related symptoms among cold workplace workers in Thailand. This study aimed to determine the prevalence of cold-related cardiorespiratory, circulatory, and general symptoms and performance degradation among Thai chicken industry workers and identify vulnerable groups. METHODS: Overall, 422 workers aged from 18 to 57 years at four chicken meat factories in Thailand were interviewed for cold-related symptoms and complaints. The results were expressed in terms of model-based adjusted prevalence and prevalence differences (PDs) in percentage points (pp) with 95% confidence intervals (CIs). RESULTS: In total, 76.1% of the respondents reported cold-related respiratory symptoms, 24.6% reported cardiac symptoms, 68.6% reported circulatory symptoms, and 72.1% reported general symptoms. In addition, 82.7% of the respondents reported performance degradation. Cold-related respiratory symptoms increased by PD 29.0 pp. (95% CI 23.4-34.6) from the lowest to the highest educational group, with a similar pattern observed in performance degradation. Forklift drivers and storage and manufacturing workers complained of cold-related respiratory symptoms more than office staff (PD 22.1 pp., 95% CI 12.8-31.3; 12.0 pp., 95% CI 2.4-21.6; and 17.5 pp., 95% CI 11.5-23.6, respectively); they also reported more performance degradation (PD 24.1 pp., 95% CI 17.0-31.2; 19.8 pp., 95% CI 14.1-25.6; and 14.8 pp., 95% CI 8.0-22.6, respectively). Weekly alcohol consumers reported more performance problems owing to cold (PD 18.2 pp., 95% CI 13.9-22.6) than non-consumers of alcohol. Cardiac and circulation symptoms were more common in women than men (PD 10.0 pp., 95% CI 1.1-18.9; and 8.4 pp., 95% CI 0.5-16.4, respectively). The age trend in performance issues was curved, with the highest prevalence among those aged 35-44 years, while the oldest workers (45-57 years) perceived less cold-related symptoms, particularly thirst. CONCLUSIONS: Cold-related symptoms and performance degradation were found to be common in this industry, with vulnerable groups comprising of highly educated workers, forklift drivers, storage and manufacturing workers, weekly alcohol consumers, aging workers, and women. The results demonstrate a need for further research on the adequacy of protection provided against the cold, particularly given that global warming will increase the contrast between cold workplaces and outdoor heat.

Prevalence of cold-related symptoms among Thai chicken meat industry workers: association with workplace temperature and thermal insulation of clothing.

This study determined the association of cold-related symptoms with workplace temperature and thermal insulation of clothing among Thai chicken industry workers. Three hundred workers were interviewed regarding cold-related symptoms, which were regressed on worksite temperature and protective clothing. In total, 80% of workers reported respiratory symptoms; 23%, cardiac symptoms; 62%, circulation disturbances; 42%, thirst; 56%, drying of the mouth; and 82%, degradation of their performance. When adjusted for personal characteristics, respiratory symptoms were 1.1‒2.2 times more prevalent at -22‒10°C than at 10‒23°C. At -22‒10°C, cardiac symptoms increased by 45%, chest pain by 91%, peripheral circulation disturbances by 25%, and drying of the mouth by 57%. Wearing protective clothing with at least 1.1 clo units was associated with marked reductions in symptom prevalence. Therefore, temperatures lower than 10°C increased prevalence of cold-related symptoms, which are largely preventable by appropriate clothing use.

Thermal comfort sustained by cold protective clothing in Arctic open-pit mining-a thermal manikin and questionnaire study.

Workers in the Arctic open-pit mines are exposed to harsh weather conditions. Employers are required to provide protective clothing for workers. This can be the outer layer, but sometimes also inner or middle layers are provided. This study aimed to determine how Arctic open-pit miners protect themselves against cold and the sufficiency, and the selection criteria of the garments. Workers' cold experiences and the clothing in four Arctic open-pit mines in Finland, Sweden, Norway and Russia were evaluated by a questionnaire (n=1,323). Basic thermal insulation (Icl) of the reported clothing was estimated (ISO 9920). The Icl of clothing from the mines were also measured by thermal manikin (standing/walking) in 0.3 and 4.0 m/s wind. The questionnaire showed that the Icl of the selected clothing was on average 1.2 and 1.5 clo in mild (-5 to +5°C) and dry cold (-20 to -10°C) conditions, respectively. The Icl of the clothing measured by thermal manikin was 1.9-2.3 clo. The results show that the Arctic open-pit miners' selected their clothing based on occupational (time outdoors), environmental (temperature, wind, moisture) and individual factors (cold sensitivity, general health). However, the selected clothing was not sufficient to prevent cooling completely at ambient temperatures below -10°C.

Evaluating cold, wind, and moisture protection of different coverings for prehospital maritime transportation-a thermal manikin and human study.

INTRODUCTION: Prehospital maritime transportation in northern areas sets high demands on hypothermia prevention. To prevent body cooling and hypothermia of seriously-ill or injured casualties during transportation, casualty coverings must provide adequate thermal insulation and protection against cold, wind, moisture, and water splashes. OBJECTIVE: The aim of this study was to determine the thermal protective properties of different types of casualty coverings and to evaluate which would be adequate for use under difficult maritime conditions (cold, high wind speed, and water splashes). In addition, the study evaluated the need for thermal protection of a casualty and verified the optimum system for maritime casualty transportation. METHODS: The study consisted of two parts: (1) the definition and comparison of the thermal protective properties of different casualty coverings in a laboratory; and (2) the evaluation of the chosen optimum protective covering for maritime prehospital transportation. The thermal insulations of ten different casualty coverings were measured according to the European standard for sleeping bags (EN 13537) using a thermal manikin in a climate chamber (-5°C) with wind speeds of 0.3 m/s and 4.0 m/s, and during moisture simulations. The second phase consisted of measurements of skin and core temperatures, air temperature, and relative humidity inside the clothing of four male test subjects during authentic maritime prehospital transportation in a partially-covered motor boat. RESULTS: Wind (4 m/s) decreased the total thermal insulation of coverings by 11%-45%. The decrement of thermal insulation due to the added moisture inside the coverings was the lowest (approximately 22%-29%) when a waterproof reflective sheet inside blankets or bubble wrap was used, whereas vapor-tight rescue bags and bubble wrap provide the most protection against external water splashes. During authentic maritime transportation lasting 30 minutes, mean skin temperature decreased on average by 0.5°C when a windproof and water-resistant rescue bag was used over layered winter clothing. CONCLUSION: The selected optimum rescue bag consisted of insulating and water-resistant layers providing sufficient protection against cold, wind, and water splashes during prehospital transportation lasting 30 minutes in the uncovered portion of a motor boat. The minimum thermal insulation for safe maritime transportation (30 minutes) is 0.46 m²K/W at a temperature of -5°C and a wind speed of 10 m/s.

The effect of cold protective clothing on comfort and perception of performance.

The physiological properties of clothing designed to provide protection against cold, windy and damp conditions affect comfort. The weight, thickness, stiffness of the fabrics and friction between the clothing layers affect physical performance. The comfort and perception of performance associated with 3 military winter combat clothing systems from different decades (the new M05 system, the previous M91 system and traditional clothing) were observed during a winter military manoeuvre. Subjective experiences concerning comfort and performance were recorded for 319 subjects using questionnaires. The most challenging conditions for comfort and performance were perspiration in the cold and external moisture. The new M05 system provided warmer thermal sensations (p < .010), dryer moisture sensations in the presence of external dampness (p < .001), dryer perspiration moisture sensations (p < .050) and better perception of physical (p < .001) and mental performance (p < .001) than the other systems. Careful development of the clothing system guarantees good comfort and performance during cold exposure.