Heat Stress and Physiological Strain of Permeable vs. Impermeable CB Protective Garment
Recruitment status was: Recruiting
Current protective clothing of any kind, especially the nuclear-biological-chemical (NBC) protective garments, amplify thermal stress because of the inherent properties of the clothing material. High insulation coefficient and low water vapor permeability of the protective cloth limit the ability of sweat to readily evaporate, which consequently result with a significant elevation of body temperature and with excessive body fluid loss (because of inefficient sweating) that might result with significant dehydration.
Combat soldiers require to perform intense physical activities under hostile environmental conditions, including in contaminated areas that need the use of protective garments. The ability to fulfill a mission derives from the soldier's professionalism and from his physiological limits. It is well established that wearing protective garments affect tolerance time (TT) and performance.
To operate in contaminated areas suitable protective garments should be worn. The inherent characteristics of the current protective garments limit, however, the effective working periods with such an ensemble, which is further aggravated in hot climate. Thus, in an attempt to increase TT and enhance work effectiveness, improved protective garments, which result with a lessened heat-stress, are under different stages of development.
The relative influence of air permeability properties, garment weight and garment construction on heat stress and physiological strain will be investigated.
The results will be quantified in terms of body temperatures, heart rate, fluid balance, subjective sensation and the maximum wear time (if necessary extrapolated).
|Study Design:||Observational Model: Case Control|
- The physiological burden of different CB Protective Garments [ Time Frame: 1 year ] [ Designated as safety issue: No ]
The physiological burden of different CB Protective Garments will be mesured by a heat tolerance test (HTT).
The subjects will undergo an HTT wearing different CB Protective Garments and the results which indicate physiological burden will be compared between the different garments.
- Rectal temperature [ Time Frame: 1 year ] [ Designated as safety issue: Yes ]The rectal temperature will be mesured by rectal thermistore.
- Skin temperature [ Time Frame: 1 year ] [ Designated as safety issue: No ]The skin temperature will be mesured by skin thermistores conected to 3 different sites (chest, leg and arm).
- Heart rate [ Time Frame: 1 year ] [ Designated as safety issue: Yes ]Heart rate will be mesured by a polar watch.
- Sweat rate [ Time Frame: 1 year ] [ Designated as safety issue: No ]The sweat rate will be calculated in each HTT from the subject's weight before and after the test and his water balance.
|Study Start Date:||December 2010|
|Estimated Study Completion Date:||December 2014|
|Estimated Primary Completion Date:||December 2013 (Final data collection date for primary outcome measure)|
|men wearing Semipermeable garment|
|air permeable garment type BP2|
|air permeable garment type BP3|
|air permeable garment type MO|
|air permeable garment type BP1|
Please refer to this study by its ClinicalTrials.gov identifier: NCT01221012
|Sheba medical center|
|Ramat Gan, Israel|
|Principal Investigator:||Amit Druyan, M.D||Medical Corps, Israel Defense Force|