Many things have changed since 1994, when the first hint of arc-rated (AR) materials hit the utilities. Back then, the best practice was to wear cotton jeans, heavy cotton shirts and heavy cotton-shell winter wear. Other personal protective equipment (PPE) like rainwear illustrated an industry problem: There were not many good flame-resistant (FR) clothing options available. At the time, the only markets for FR garments were military, aviation and refineries. Non-melting rainwear was not really on the market since most “FR” rainwear at that time was made of nylon or polyester, which means it melted and thus didn’t meet OSHA requirements.
In the years immediately following the promulgation of the 1994 version of OSHA’s 29 CFR 1910.269 standard, a few utilities began using AR shirts. However, in a 2001 IBEW survey, only 68 percent of utilities reported using AR shirts and rainwear. There was a false belief that cotton was somehow FR, but this was a misinterpretation of ASTM data provided to OSHA about heavy, 11-oz/yd² cotton. Any utility that had done calculations using ARCPRO – software that computes the thermal parameters of electrical arcs – knew it was basically impossible to justify not moving to AR garments given the available data. In the same IBEW survey, 70 percent of respondents reported using FR clothing – which was commonly used interchangeably with “AR clothing” at the time of the survey – as part of a uniform required by the company for which they worked. The tides were turning even then toward company-provided AR garments for line technicians.