Your best source for complete information on the NFPA 70E Standard is via the actual standard, available for purchase at www.nfpa.org. In 2000, the NFPA 70E Standard first addressed electric arc flash hazard and required flame resistant arc flash clothing to protect workers. The current edition of the NFPA 70E standard was released in 2012, and further details personal protective equipment.
Fluoride ions exist predominantly as hydrofluoric acid in acidic environments with a pH below 5.2. Fluoride ions corrode the glass. Therefore, the pH measurement with the glass electrode for a solution which includes fluoride ions is basically impossible. Although the useful life of the electrode may be shortened, however, the measurement with immersing the electrode in the sample for a given short time is possible.
Guidance on the concentration of fluoride has been present in the Guidelines since 1983. Like other countries with water fluoridation programs, Australia has organised anti-fluoride groups that contest the health benefits of fluoride.uidance on the concentration of fluoride has been present in the Guidelines since 1983. Like other countries with water fluoridation programs, Australia has organised anti-fluoride groups that contest the health benefits of fluoride.