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).
Trout Science. The brook trout is a brilliantly colored fish. It is readily identified by the white leading edge, backed by black, on its lower fins. A true delight to fish for, these generally small fish have a true wild nature. Due to over fishing, and competition with rainbow and brown trout, their range now is greatly reduced in most states. Habitat: Brookies are found almost exclusively in the cold, clear, fresh water streams of the mountains.