Thermal properties of three sets of garments measured with a heated sweating mannequin
Författare
Redaktör
- Ingvar Holmér
- Kalev Kuklane
Summary, in English
The choice of proper insulation for cold protection is important. However, “proper insulation” depends on activity and at lots of jobs the activity varies along the working day. The choice of low insulation for high metabolic rate makes people feel cold during low activity levels and the choice of high insulation for low metabolic rate makes them feel hot and sweat during high activity levels. The sweating increases the heat losses through evaporation and reduces the insulation due to wetting of insulation layers. With moist clothing often accompanies strong discomfort sensation.
The insulation of 3 sets of protective garments were measured on a sweating thermal mannequin. The tests were carried out both without and with sweating. During sweating tests the water was supplied to the mannequin at a rate of 200 g/m2h.
Sweating affected the heat balance to a considerable amount. This effect was bigger in clothing with better water vapour permeability, and it was higher at higher ambient temperature (about 35 % at 0 degrees C and 40 % at +10 degrees C). In a clothing set with impermeable outer layer the difference due to environmental temperature was very small and at both temperatures the difference stayed around 13 %. The differences in Itot,corr values for the dry and sweating measurements show the reduction of insulation due to wetting of insulation layers. For two sets with lower insulation the difference was 7-8 % at +10 degrees C, while the difference for warmest/impermeable set at the same temperature was almost 20 %. However, at 0 degrees C this difference was 9-14 % for all garments.
The insulation of 3 sets of protective garments were measured on a sweating thermal mannequin. The tests were carried out both without and with sweating. During sweating tests the water was supplied to the mannequin at a rate of 200 g/m2h.
Sweating affected the heat balance to a considerable amount. This effect was bigger in clothing with better water vapour permeability, and it was higher at higher ambient temperature (about 35 % at 0 degrees C and 40 % at +10 degrees C). In a clothing set with impermeable outer layer the difference due to environmental temperature was very small and at both temperatures the difference stayed around 13 %. The differences in Itot,corr values for the dry and sweating measurements show the reduction of insulation due to wetting of insulation layers. For two sets with lower insulation the difference was 7-8 % at +10 degrees C, while the difference for warmest/impermeable set at the same temperature was almost 20 %. However, at 0 degrees C this difference was 9-14 % for all garments.
Publiceringsår
1998
Språk
Engelska
Sidor
79-81
Publikation/Tidskrift/Serie
Arbete och hälsa
Issue
1998:18
Dokumenttyp
Konferensbidrag
Förlag
Arbetslivsinstitutet, Stockholm, Sweden
Ämne
- Production Engineering, Human Work Science and Ergonomics
Conference name
Problems with cold work
Conference date
1997-11-16 - 1997-11-20
Conference place
Grand Hôtel Saltsjöbaden, Stockholm, Sweden
Status
Published
Forskningsgrupp
- Thermal Environment Laboratory
ISBN/ISSN/Övrigt
- ISSN: 0346-7821
- ISBN: 91-7045-483-3