Manual performance deterioration in the cold estimated using the wind chill equivalent temperature.

Area of Science:

• Occupational Health
• Environmental Physiology
• Human Factors Engineering

Background:

• Manual performance, crucial for many jobs, is impaired in cold, windy conditions.
• Existing predictors of dexterity loss due to climate are limited.
• Understanding these impacts is vital for workplace safety and efficiency.

Purpose of the Study:

• To investigate the impact of various cold and windy conditions on finger dexterity, hand dexterity, and grip force.
• To identify reliable predictors of manual performance decrease based on climatic factors.
• To evaluate the effectiveness of standard cold-weather work clothing and extra insulation.

Main Methods:

• Controlled climatic chamber experiments with nine combinations of temperature (-20°C to 0°C) and wind speed (0.2 to 8 m/s).
• Assessment of finger dexterity using the Purdue pegboard test and hand dexterity with the Minnesota manual dexterity test.
• Measurement of grip force using a hand dynamometer on twelve subjects exposed for one hour.

Main Results:

• Manual performance deterioration was strongly correlated with Wind Chill Equivalent Temperature (WCET) and the square root of exposure time (r=0.93).
• Extra insulation (parka) affected subjective cold sensation but did not significantly improve manual performance.
• No significant difference in manual performance was observed between conditions with and without extra insulation.

Conclusions:

• WCET and exposure time are significant predictors of manual performance decline in cold environments.
• Simple models based on WCET and exposure time can help assess risks associated with cold-weather work.
• Further research is needed to establish critical dexterity values for diverse operational tasks in cold conditions.