The only thing âpositiveâ about a Gentle Leader is that you use clickers and food to bribe the dog to let you put it on. They hate it. Gentle Leader or medieval torture device? What is more cruelâa prong collar or a Gentle Leader? A lot of people will point to the prong collar, mainly because they arenât educated in how they work. And after all, a Gentle Leader is â¦. gentle. But donât let the soft straps and cheerful colors fool you. Head halters are far more aversive than a prong collar.
Definition. 1  A Permissible Exposure Limit (PEL) is the maximum amount or concentration of a chemical that a worker may be exposed to under OSHA regulations. 2  A Time-Weighted Average (TWA) is explained below. 3  A VPEL or Vacated PEL is an older PEL set by OSHA but later vacated (retracted) under court order.
Below is some information on the major occupational exposure values. Permissible Exposure Limits (PELs): The Occupational Health and Safety Administration (OSHA) has set permissible exposure limits (PELs) on the amount or concentration of a substance in the air.ome of the PELs are listed as ceiling values â concentrations above which a worker should never be exposed, or short-term exposure limits (STELs) âaverage concentrations which should not be exceeded over a 15 minute time period. It is important to note that the PELs tend to be higher than other published values.