The NCDC heat stress index
, which extends the work of Gaffen and Ross (1998), has classified an extreme heat event as any day in which the minimum, maximum, or average apparent temperature exceeds the 85th percentile of the base period (1961-1990) for each first-order weather station included in the database.
Abbreviations: GDD, growing degree days with a 5 [degrees] C baseline temperature; [H.sub.i], heat stress index
; MR, main raceme yield contribution to total plant yield; SF, seed weight per flower established; SR, success ratio; [T.sub.F], threshold heat stress temperature.
Has a mine climate simulation program been used to help predict working place temperatures, humidity, and heat stress index
, and, if needed, assisted in the design of adequate and efficient airflow and air cooling systems?
Our sports medicine staff uses a "sling psychrometer," a hand-held instrument that measures the heat stress index
before every scheduled workout or practice.
Apparent temperature (AT), or the heat index, is perhaps the best known and most widely used heat stress index
. The Canadian weather service uses the Canadian-developed humidex, rather than AT.
 The different heat stress indexes
depend primarily on air temperature and humidity.