airjockey42 wrote:
I have a little confusion as to "Level" and "Category". Since there is no Category/Level 0 PPE why does NFPA 70E still define 5 levels of PPE and only 3 levels of Incident Energy? It appears that Level 2 and 3 PPE can be used in Level 2 of Incident energy, depending on the value of that number, but I think it just adds more confusion for the man in the field.
Using a hood decreases visibility and the heat load with level 2 PPE is not significantly different from standard cotton workwear, but there is a substantial increase in heat load and thus risk of heat related injuries above about 12 cal/cm2. So I think you mean no reason to have level 3 because 3 and 4 can be combined, and no site I know of bothers with level 3. I haven't studied the current equipment table closely but few tasks list level 3. Any PPE equal to or greater than the required level if for instance 3 is dropped is acceptable.
The old tables lowered the category depending on the task because the used a risk ranking method where it was assumed that probability of injury and magnitude of hazard were equivalent. Wearing for instance level 1 PPE where the hazard is level 2 because the likelihood of injury is decreased is the same as not wearing any PPE. The 2015 tables fixed this by first determining if any PPE at all is required and then specifying the same level for a given type of equipment.
