About cold, LEARN MORE
Individual cold stress
Three basic components affect human heat balance: thermal environment, thermal insulation of clothing and heat production by physical work or shivering. In addition, individual differences affect cold tolerance (figure). The most important individual factors decreasing cold tolerance are health problems, aging (with decreased ability for heat production), poor fitness and lack of adaptation. Some individuals have also poor circulation in hands and feet which make them sensitive to cold. For more information, see e.g. [Rintamäki: Work and wellbeing in cold; Lecture in Arctic Frontiers 2014].
Low temperature is naturally the main cause of cold stress and wind increases heat loss as shown by wind chill index. In springtime sunshine moderates cold stress as we can get even 100 W heat from it.
Weather forecasts and cold warnings
National meteorological institutes provide local weather forecasts which are useful for the planning of work. Finnish Meteorological Institute has a special warning system for cold and heat: http://ilmatieteenlaitos.fi/tietoa-helle-ja-pakkasvaroitukset(in Finnish).
The existing warnings can be found from: http://ilmatieteenlaitos.fi/varoitukset (in Finnish)
A warning will be given if temperature or wind chill index is colder than:
- -20, -30 or -35 °C in Southern Finland (indicating very cold, risk of frostbite or great risk of frostbite, respectively)
- -25, -35 or -40 °C in Middle Finland
- -30, -40 or -45 °C in Northern Finland.
Standards as tools
There are a lot of standards which are “handbooks” how to estimate e.g. ambient thermal conditions, human thermal strain and the thermal properties of the clothing. See e.g. the abstracts of Jussila (page 23) and Rintamäki and Rissanen (p47) in: http://minehealth.eu/wp-content/uploads/2012/10/Abstract-book-of-the-3rd-Barents-Occupational-Health-Workshop.pdf