The NFPA 70E Standard details multiple levels of Hazard Risk Categories (HRC) [see table 1.1], also called Levels. The greater the risk: the higher the HRC. Arc Rating is the factor that indicates which HRC is necessary, and can be measured in either ATPV or EBT.
The optimal pH range for brook trout appears to be 6.5-8.0,with a tolerance range of 4.0-9.5.Brook trout occur in waters with a wide range of alkalinity and specificconductance, although high alkalinity and high specific conductance usuallyincrease brook trout production (Cooper and Scherer 1967).
We assume that an area ~ 25% of thetotal stream area occupied by brook trout will provide adequate cover.Embryo. Temperatures in the range of 4.5-11.5Â° C have been reported asopti mum for egg i ncubation (MacCrimmon and Campbell 1969). Length of eggincubation is about 45 days at 10Â° C, 165 days at 2.8Â° C (Brasch et al.