OSHA’s purpose is to mandate that people work in a place free from known and recognized hazards. This must be every employer’s priority and the focus of all of occupational health and safety programs, regardless of where the workplace is or the type of work being performed.
When it comes to safe electrical work, NFPA 70E, Standard for Electrical Safety in the Workplace, comes into play. Section 110.1 requires us to eliminate the hazard first, and this is by far the most effective method for keeping employees safe. However, there are times where electrical work needs to be performed on equipment that has not been placed in an electrically safe work condition or other measures are unavailable to reduce the risk of injury to a satisfactorily low level.
Bring the mandate on site
Often this means that the employer provides the employee with personal protective equipment that aims to reduce the severity of injury to a survivable level. To do so, the employer needs to verify that the PPE they provide employees is legitimate, which is where it gets tricky for certain items. OSHA and NFPA 70E state that when an employee must work exposed to hazards that have not sufficiently been controlled to reduce risk of injury, additional protection measures must be taken.
Protecting employees from shock hazards is relatively straightforward. Provide voltage-rated gloves with leather protectors based on the system voltage that they will be working with. There are even a couple of standards that help employers ensure that these gloves are going to give them every advantage possible. First, the employer wants to look for ASTM D120 on the label to verify that the gloves were initially constructed to the standard’s specifications. As long as the gloves are cared for in accordance with ASTM F496, mainly ensuring dielectric testing at intervals not exceeding 6 months, the gloves do a decent job of reducing risk exposure. OSHA even makes note in 1910.137 that gloves meeting these ASTM documents are in compliance.
Arc flash PPE
However, arc flash PPE is another beast, as OSHA doesn’t address arc flash hazards in general. Section 1910.269 covers arc flash, but that is specific to generation, transmission and distribution systems. For the rest of us, the best we can find is that arc flash injuries fall under the category of “or other injuries” in 1910.333(a). This is where NFPA 70E joins the party. OSHA states that we must adopt safety-related work practices to protect against these “other injuries,” and NFPA 70E tells us how to do it.
Section 130.7(C)(1) requires that workers inside the arc flash boundary must wear arc-rated PPE and that all parts of the body inside the arc flash boundary are protected. Unfortunately, this is where the “black and white” information about arc flash PPE ends. How does an employer ensure that the provided PPE is adequate? There are product standards for arc-rated PPE, but NFPA 70E doesn’t require that PPE meeting these standards is used. NFPA 70E doesn’t require that we follow any document other than NFPA 70E; it’s a rule in the NEC Style Manual, which governs how NFPA 70E is written.
OSHA’s requirement of a workplace free from hazards becomes our guiding light. Employers must develop best practices when it comes to arc flash PPE. Certainly, we can verify that the PPE meets ASTM F1506 for arc-rated clothing. This document requires garments to have an arc rating and includes items such as fabric color-fastness and whether the garment will shrink. All we need to ensure is an adequate arc rating, ATPV or EBT, which can typically be found on the garment’s interior tag. If it meets ASTM F1506, it will have such a rating.
However, the clothing doesn’t have to meet ASTM F1506 to carry an arc rating, since the test method for arc-rated materials is described in ASTM F1959. This might be useful for garments that carry multiple types of ratings. For instance, it is very common to see garments marked as “FR” on the sleeve and find “ATPV = 8.6 cal/cm2” on the tag inside. Another example is a garment that has “NFPA 2112 | CAT 2” on the exterior tags. Many of these dual FR/AR garments meet ASTM F1506 and NFPA 2112 and are acceptable in arc flash exposures.
This can be very confusing to navigate. Keep in mind that the goal of arc-rated PPE is to reduce the injury severity to a survivable level. This means that the PPE must have an arc rating above an employee’s estimated exposure level. It is imperative to inspect arc-rated PPE for damage, wear and contamination before each time it is worn. Remember, the key to arc flash PPE is to wear it, care for it, inspect it and treat it as though life depends on it, because it does.