11.1 – Overview of Arc Flash PPE Minimum Ratings
CSA Z462-24 has removed category ratings and focused on the cal/cm2 value of the protection. Levels are broken into MINIMUM cal/cm2 ratings.
There is often reference to the ATPV (Arc Thermal Protection Value), however all considerations should focus on the caloric heat protection expressed as cal/cm2. Compare the value to the overall worker protection to ensure that even the weakest point, meets or exceeds the required cal/cm2 expected to be released in the event of an incident.
CSA Z462-24 changed Table 3 Table 2 and included it could be used for EITHER incident energy analysis or table section method as a quick determination of PPE. Remember you MUST ALWAYS, ensure your protection matches or is greater to the incident energy.
Table 2 Selection of arc-rated clothing and other PPE when the incident energy analysis method or an arc flash PPE selection table method is used
Incident energy exposures equal to 1.2 cal/cm2 (5 J/cm2) up to and including 12 cal/cm2 (50 J/cm2)
Arc-rated clothing with an arc rating equal to or greater than the estimated incident energy*
• Arc-rated long-sleeve shirt and pants or arc-rated coverall or arc flash suit (SR)
• Arc-rated faceshield and arc-rated balaclava or arc flash suit hood (SR)†
• Arc-rated outerwear (e.g., jacket, parka, rainwear, hard hat liner, high-visibility apparel) (AN)‡
Heavy-duty leather gloves, arc-rated gloves or rubber insulating gloves with protectors (SR)§
Hard hat
Safety glasses or safety goggles (SR)
Hearing protection
Leather footwear**
Incident energy exposures greater than 12 cal/cm2 (50 J/cm2)
Arc-rated clothing with an arc rating equal to or greater than the estimated incident energy*
• Arc-rated long-sleeve shirt and pants or arc-rated coverall or arc flash suit (SR)
• Arc-rated arc flash suit hood
• Arc-rated outerwear (e.g., jacket, parka, rainwear, hard hat liner, high-visibility apparel) (AN)‡
Arc-rated gloves or rubber insulating gloves with protectors (SR)§
Hard hat
Safety glasses or safety goggles (SR)
Hearing protection
Leather footwear**
Legend:
SR = selection of one in group is required
AN = as needed
** Footwear other than leather or dielectric may be used, provided it has been tested for and demonstrates no ignition, melting, or dripping at or greater than the estimated incident energy exposure.
Note that there are many Arc Flash suits on the market that have greater than 75 ratings. There are 100, 125 and 150 cal/cm2 available. The suit should be matched to the incident energy your faced with as close as possible, or laying should be used to reach the desired protection.
