Heat Index
Heat Stress Risks and Exercise Guidelines
|
||
Heat Index
The heat index combines air temperature and relative humidity to determine an apparent temperature, or how hot it actually feels. Think of it as you do a wind-chill index. High heat-index days can be health and life threatening even to the non-exerciser. Imagine how much riskier internal heat-producing aerobic endurance activities are, when one starts out in a heat-hazardous environment.Heat Index Chart
Temp Dew Point(F) (F) 50.0 55.0 60.0 65.0 70.0 75.0 80.0 85.0 --------------------------------------------------- 65: 62.7 63.8 65.0 66.6 70: 67.8 68.7 69.8 71.1 72.6 75: 73.1 73.9 74.8 75.9 79.2 80.7 80: 79.8 80.6 81.6 82.8 84.4 86.9 90.9 85: 83.5 84.7 86.1 88.0 90.5 94.0 99.0 106.6 90: 87.9 89.4 91.2 93.6 96.9 101.2 107.2 115.6 95: 92.9 94.5 96.7 99.6 103.4 108.4 115.2 124.3 100: 98.1 99.9 102.4 105.6 109.8 115.3 122.7 132.3 105: 103.4 105.4 108.1 111.6 116.1 122.0 129.7 139.7 110: 108.7 110.9 113.8 117.5 122.3 128.4 136.3 146.5
Any value less than 80 is considered comfortable.
Any value greater than 90 is considered extreme.
Any value greater than 100 is considered hazardous.
Any value greater than 110 is considered dangerous.
Humidity
Humidity is the amount of moisture in the air. Humidity is of particular concern to aerobic exercisers whose primary cooling mechanism is perspiration evaporating. It's the evaporation of that perspiration that causes some cooling effect, not the process of perspiring itself. In other words, in water-vapor-saturated air (high humidity), there is no evaporation of perspiration, and therefore, our principle cooling mechanism is not functioning for us.Dew point
Dew point is the temperature at which a vapor begins to condense. Dew points are sometimes reported and/or used rather than relative humidity. Beware of dew points above 70.Next page > Heat factors to consider when you’re walking> Page 1, 2, 3, 4, 5, 6
