Q: Are there any changes to steel-toe boot requirements for lineworkers in the recently revised OSHA 1910.269 standard?
A: OSHA still leaves it to employers to decide whether hard-toe or protective footwear is required. As with all other PPE, the decision should be made based on risks and history. Wearing safety footwear is not required by the PPE rule. However, what is required in OSHA 29 CFR 1910.136, “Foot protection,” is a mandatory assessment of the work environment. The rule states that the employer “shall ensure that each affected employee uses protective footwear when working in areas where there is a danger of foot injuries due to falling or rolling objects, or objects piercing the sole, or when the use of protective footwear will protect the affected employee from an electrical hazard, such as a static-discharge or electric-shock hazard, that remains after the employer takes other necessary protective measures.”
You might think that if we work with round poles, protective shoes are automatically required, but that’s not necessarily the case. Take a look at OSHA’s response in an August 2003 letter of interpretation to Heather Siemon regarding office workers in a factory setting (see www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=24639): “If you are exposed, however infrequently, to those hazards during your interaction with warehousing activities or pharmacy activities, then, during that period of exposure, you would be required to wear protective footwear. If an employee is not exposed to any hazards to the feet, then the use of protective footwear would not be required.”
This is where the last part of the OSHA 1910.136 rule comes in, which references hazards that remain after an employer takes other necessary protective measures. This part is not just about electrical hazards. Remember that PPE is the last means of protecting employees from workplace injuries. However, if the employer can show that risks are controlled by barriers, procedures or practices, there is no exposure. The employer does have to be able to show that the means of protection are viable, and for practical reasons that includes training and enforcement of those protective means.
Q: We are trying to determine when our lineworkers and metering techs would need to complete an energized electrical work permit per the OSHA standards compared to the NFPA 70E guidelines. What exemptions apply to high-voltage utility work aside from testing and troubleshooting tasks?
A: For the purposes of clarity, we believe you are referring to the energized electrical work permit required by NFPA 70E Article 110.8(B)(2); the format for the permit is described in Article 130.1(B). We will refer to the permit here as an energized work permit.
First, we are not aware of any OSHA requirement for an energized work permit for the work classifications you asked about. You are also not the first person to be confused regarding the NFPA 70E rule. Specific to your question, line work and metering are not covered under 70E. You will find the exemptions on the first page of 70E in Article 90.2(B). There are several classes of exemptions listed, but to save space we will address just one here: “(B) Not Covered. This standard does not cover: (5) Installations under the exclusive control of an electric utility where such installations (c) Are on property owned or leased by the electric utility for the purpose of communications, metering, generation, control, transformation, transmission, or distribution of electric energy …”
Over the years OSHA has referred to 70E for some of the valuable information employers may use in developing compliance practices, and this has helped to confuse the issue. NFPA 70E applies to facilities electrical maintenance in particular. To save space, we'll refer to it here as commercial electrical. The basic policy for this type of work is that no energized work will be done with the exception of very specific instances. The idea of the energized work permit is to assure the no-hot-work policy. The design of the energized work permit is to analyze the required work against the 70E exceptions and ensure that the work meets the criteria and justifies the energized work. The difference between commercial electrical work and utilities is very stark here. For the most part utilities is just the opposite. Utility work is usually done energized when customers are affected, and a justification typically has to be established to de-energize the customer. In other words, commercial electricians are prohibited from working hot; utilities work hot as a rule. The only place utility installations would fall under 70E is in facilities like offices that are not directly tied to the systems serving the facilities that are exempt.
Lastly, this doesn't mean some parts of 70E can't be used to make a utility workplace safer, but not all 70E provisions have a practical place in the utility industry. Some parts, like the arc flash calculations, could be very misleading if applied to utility exposures. Be cautiously selective.
Q: We had arc flash studies done in December 2014 and January 2015; they were labeled with the 2012 NFPA 70E standards by the engineering firm for our non-T&D generation facilities. From a safety and compliance standpoint, does it matter if the studies did not follow the 2015 standards with reference to the changes in the arc flash labels? In other words, although not required by OSHA, could we be cited for not using the latest guidelines when the arc flash studies were conducted?
A: First, to be clear, we do not think generation facilities under the exclusive control of a utility require the NFPA 70E arc flash labels because such facilities are exempt under 70E Article 90.2(B)(5).
In response to your direct question, there is always the argument that upgrading to a more current standard would provide better protection. But assuming we understand your question correctly, we do not feel that you could be cited. OSHA rarely requires employers to go back and update existing facilities that comply with an earlier standard. If they did make such a demand, it would be due to a serious safety issue that existed under previous standards. OSHA would clearly say so in the rule, or they would issue an interim or emergency rule. However, like most codes, upgrading safety labels would not be required unless the facilities were going to be replaced or substantially upgraded.
Q: In terms of of cover-up materials, what's the difference between primary and secondary protection?
A: Primary protection, if referring to barriers, consists of those devices that can be periodically tested to ensure their electrical integrity. These include rubber goods such as gloves, sleeves and blankets as well as hard cover that can be reasonably inspected.
Secondary protections are generally items like overshoes or roll insulating material that can be part of a system of protection but have no acceptable means by which to periodically test their electrical value.
Q: Can you address the prohibition of grounding through a switch?
A: I have heard people say the rules prohibit grounding through a switch, but I think they are confusing utility procedures with the National Electrical Code rule that requires the grounding electrode conductor to be continuous without connections or switches. I am not aware of any regulations that prohibit working on the other side of a closed switch. We do it all the time in substations. We are aware that when switches are in a bus, some companies require jumpers or additional bus grounds as well as personal grounds, in addition to the bus grounds or grounding switches.
If you think of a three-phase system grounded and bonded together, the individual phases are all at a relatively equal potential with the exception of resistances that might be in the parallel conductors or switches. With that in mind, there could be a problem if a worker was shunting a closed switch with his body and the switch had resistance across it. The same could be said for a switch that was opened in the grounded scheme. If one switch in a set of three was opened, the other two would act as jumpers, bypassing the open switch and reducing the risk. But the risk is real and could be deadly. With an open switch or high resistance across a switch for the moment of inadvertent energizing – or even in the case of induction – there would be a voltage drop across the switch as the current flowed through it. There would have to be a fairly high resistance in all three switches to create a high enough voltage drop, usually established as 50 volts, but it could be possible.
People have asked if they should ground on both sides where there is a switch, but if impedance across a switch was a concern for nearby workers, it would be solved by installing a mechanical jumper across it more effectively than on both sides of the closed switch. Obviously, utilities and contractors should identify switches in the grounded scheme to ensure no one opened a switch and, in doing so, inadvertently removed protected grounding on the side not grounded.
Q: I am a contractor working on a mine site under MSHA jurisdiction. My co-workers and I were told by the mine’s safety department that workers on a bucket truck had to be protected from falls on their way to getting in the bucket. Is that an MSHA rule?
A: We receive questions similar to yours about three to four times a year. MSHA regulations are centered on mining operations. There are very few rules in the MSHA safety standards that apply to overhead construction. MSHA's regulations are not as detailed as OSHA’s when it comes to fall protection, so without the OSHA criteria to judge fall protection requirements or performance, some mines have difficulty determining what is feasible and what is not.
To persons in the overhead distribution field, there is no practical way to implement fall protection. Any type of arrest system would still allow striking the floor, turret or other structure. The ANSI equipment standard addresses safety for workers crossing equipment, mandating strategically placed handholds, footholds and improved walking routes/surfaces to reduce fall potential. OSHA as well as MSHA require those devices to be maintained.
From a regulatory standpoint, OSHA falls back on the walking and working surfaces rule. In Letter # 20070417-7634 from March 2009 (see www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=27032), the administration explained that fall protection standards in 1926 Subpart M specifically exempt mobile equipment. OSHA then stated, “The phrase ‘walking/working surface’ is defined at 29 CFR 1926.500(b)(2) as: Any surface, whether horizontal or vertical on which an employee walks or works, including, but not limited to, floors, roofs, ramps, bridges, runways, formwork and concrete reinforcing steel but not including ladders, vehicles, or trailers, on which employees must be located in order to perform their job duties. [Emphasis added].”
I believe the question on grounding through a switch is derived from the note in 1910.269(n) which states: Note to paragraph (n)(4): American Society for Testing and Materials Standard Specifications for Temporary Protective Grounds to Be Used on De-Energized Electric Power Lines and Equipment, ASTM F855-09, contains guidelines for protective grounding equipment. The Institute of Electrical Engineers Guide for Protective Grounding of Power Lines, IEEE Std 1048-2003, contains guidelines for selecting and installing protective grounding equipment.
My question is this--Does the switch meet these standards? If not, have we failed to comply with the standard? Thanks in advance for your consideration of this comment and we really appreciate what you do to promote safety in the utility industry.
Eddie, thanks for the suggestion and I apologize for not getting to this comment earlier. There is no issue with grounding through a substation ground switch as long as line crews are not using the switch as the sole source of protective grounds on the system while they are working on it. The reference in IEEE1048 refers to incorporating substation grounding switches into the temporary protective scheme. 1048 points out that the switch closed can reduce the level of current at the grounding location but that protection varies according to the source of the unexpected re-energizing so it shouldn't be calculated to reduce the size of the grounding cables without careful consideration. If the source of un-expected energizing was the station the ground switch will play a big role in reducing current out on the line. If the source was a foreign system the switch would have less impact. The 1048 standard also notes that a grounding switch can serve as a ground path to help reduce induction and aid in the performance of voltage detectors making pre-grounding voltage testing more confident. IN any case, closing the station ground switches do provide a benefit in the personal grounding scheme but like any connection in a personal protective grounding system both the benefits and limitations should be understood.
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