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April – May 2024 Q&A

Q: We recently participated in a safety seminar during which OSHA’s digger derrick/crane exemption was discussed. We have used the exemption with digger derricks to raise baskets of travelers to pole-tops for wire-pulling installation. Are we in compliance if we are not using a certified crane operator for this work?

A: Our interpretation of the OSHA rule indicates that your use of the digger derrick exemption is incorrect. Here’s a little history: OSHA’s Cranes and Derricks in Construction (29 CFR 1926.1400) final rule of 2010 included the exemption of digger derricks. In October 2012, OSHA published the direct and final rule, clarifying the digger derrick pole truck exemption from the Cranes and Derricks in Construction standard and asking for further comment. Finally, with no significant comments from the industry, OSHA withdrew the direct and final rule, issuing the final rule with preamble discussion and explanation in 2013. During this period, OSHA added setting pads and padmount transformers to the digger derrick exemption.

In 1926.1400(c), the published rule states that Subpart CC (i.e., the Cranes and Derricks in Construction standard) “does not cover digger derricks when used for augering holes for poles carrying electric or telecommunication lines, placing and removing the poles, and for handling associated materials for installation on, or removal from, the poles …” The rule – especially in light of the preamble discussion – is very clear, precisely worded and does not cover raising baskets of travelers to the pole-top. The preamble discussion clearly centers around “material,” such as transformers. In the expansion of the exemption to padmount transformers, though the language does not limit the exemption of single-phase pads, the discussion comparing the weight of a padmount transformer to the weight of an aerial transformer clearly limits the expanded exemption to a single-phase padmount transformer and the pad upon which it sits.

Keep in mind, the Cranes and Derricks in Construction operator certification only applies to construction. It does not apply to general maintenance. The difference is like-for-like replacement. General industry maintenance is replacement of a 40-foot wood pole with a 40-foot wood pole, or replacement of a 37.5-kVA transformer with a 37.5-kVA transformer. If the replacement is an upgrade, that is construction. The same apples for substation work. Lifting steel, apparatus or rebar cages is construction. However, if I’m replacing a bent steel structure leg with a good steel structure leg, that is like for like and would not fall under the definition of construction.

Instruction to compliance officers comes in the form of OSHA’s CPLs. CPL 2-1.38 (see defines maintenance as the “repair of specific limited portions of electrical systems with ‘replacement in kind’ parts to keep them in operation” and states that it is “covered by the general industry standards.”

Lastly, a warning from OSHA in the preamble states the following: “If OSHA finds that employers are using digger derricks increasingly for other tasks, the Agency may revisit this issue and adjust the exemption accordingly.” So, as they say, it is what it is. The exemption is clearly limited, but abusing it could remove it altogether.

Q: In switching and tagging in distribution, the rule says to “render inoperable.” How should we apply that? Do we remove a dropout barrel or perform some other drastic step?

A: OSHA 1910.269(m) is titled “Deenergizing lines and equipment for employee protection.” Rule 1910.269(m)(1) states that this section applies to the de-energizing of transmission and distribution lines and equipment for the purpose of protecting employees. So, this section is the employer’s minimum guidance for the protection of employees when opening and closing switches and energizing and de-energizing systems. How the employer accomplishes protection of the worker is entirely up to the employer, with some guidelines in place through OSHA 1910.269(m) and the National Electrical Safety Code. In your example, we usually apply tasks like removing a barrel when we are going to leave the control point to work elsewhere on the circuit.

To understand how OSHA would view the employer’s policies, we can look at the agency’s commentary in the preamble regarding the transmission and distribution switching and tagging rules. OSHA wrote in the 1994 preamble to 1910.269 that there are several factors that have contributed to the utility industry’s successful use of tagout programs: detailed energy control procedures; extensive training programs to teach their employees about their energy control procedures, including the use of tags and the importance of obeying them; periodically reinforcing policy with retraining; and discipline in following the policy and procedures. OSHA further wrote that to be successful, a tagout policy requires constant vigilance to assure that tags are properly applied; that they remain affixed throughout the servicing and maintenance of equipment; and that no employee violates the tag by re-energizing the equipment, either intentionally or inadvertently, before the tag is removed.

OSHA would expect the method of rendering inoperable to have some degree of difficulty. The preference is a form of mechanical impediment, such as a lock. However, since switches don’t have hasps or locks, a reasonable method is to remove the barrel or stinger if you are leaving the pole. Of course, the placement of a tag with an absolute degree of discipline regarding tags is also part of the equation. If you are at the switch pole working, you have control over it so that no extraordinary steps are needed.

Also, OSHA does not consider a nonqualified member of the public as likely to try to close an aerial switch. Of course, ground-level operators are a different issue, so they come with locking capabilities. What makes our switching and tagging effective might be boiled down to these four ingredients:

  1. A well-written policy guided by OSHA 1910.269(m) and Part 442 of the NESC.
  2. Extensive training for personnel. Remember, even the most well-written program is only as good as the training you do when you roll it out.
  3. Periodic review of the effectiveness of the program and supplemental training opportunities.
  4. Accountability across management, supervision and operators regarding the proper implementation of the policy. Rigor and discipline: Make them part of your safety culture.

Q: We are struggling with the interpretation of “primary means of protection” and “secondary means of protection” as used in the NFPA and other consensus standards. Does “primary” refer to distribution voltage or specifically to the first line of defense against electrical exposure?

A: First, as used in the standards, “primary” protection means the first line of protection for the worker. Primary protection generally refers to a device or barrier that is frequently inspected and periodically tested under specified conditions. So, primary protection would be a worker in a bucket truck using rubber gloves. The tested and inspected rubber gloves are the worker’s primary means of protection. The boom of the worker’s bucket truck that gets electrically tested periodically and wiped down occasionally is a second layer of protection often referred to as “secondary.”

With rubber gloves, be careful applying NFPA. NFPA 70E, which many knowledgeable people reference, does not apply to our work. See the very first paragraph of the scope in 70E Article 90(B), which states that the standard does not cover safety-related work practices for installations under the exclusive control of an electric utility. Part 4 goes on to define those electric utility examples. IEEE 516, “IEEE Guide for Maintenance Methods on Energized Power Lines,” is a good resource for best practices.

Regarding glove ratings, rubber gloves are not rated for use above 46 kV and are applied based on the phase-to-ground exposure of the conductor you will be entering the minimum approach distance for, assuming all other exposures (phases) are covered.

This will surprise many readers, but there is no mandatory electrical testing frequency for hot sticks. There is nothing wrong with electrically testing hot sticks, and many companies test twice a year. The rule from OSHA is that hot sticks must get thoroughly inspected every two years (see 1910.269(j)(2)). They only require electrical testing if the tool has been refinished or repaired. This is because hot sticks are to be inspected and wiped before every use. This has proven to be a very effective and safe method of ensuring the performance of hot sticks.

This may also surprise some readers: There is not and never has been a requirement to use rubber gloves with a hot stick for any application. Many employers do require the use of rubber gloves with hot sticks. This use – like climbing poles with rubber gloves – is fine, but it is a fairly new evolution of employer-chosen work requirements in the last decade.

Q: We are having a debate regarding who is qualified to enter a conventional open-bus transmission-distribution substation. It all began when a substation crew unexpectedly stumbled upon relay engineers in a substation where they were switching. What is the rule, and why are engineers not qualified to enter a substation?

A: Engineers are just as qualified to enter a substation as a Walmart greeter – unless the substation is energized. That, of course, was a tongue-in-cheek response that means no disrespect to our engineers. Transmission and distribution engineers spend many years intensely studying not only electrical principles but also electrical physics, relay and control, and often structural and civil construction and design. It’s no wonder they would expect to be qualified to enter a substation at will, but that is not necessarily how OSHA sees it. The same applies for a transmission and distribution lineworker. Many years of training and experience do not necessarily qualify them to enter a substation. It does not matter what your classification, background, education and training encompass; you must meet the requirements of the 1910.269(a)(2) standard in order to be considered qualified.

The 1910.269(a)(2) standard specifically requires training in the following:

  • Safety-related work practices and procedures.
  • Applicable emergency rescue procedures.
  • The skills and techniques necessary to distinguish exposed live parts from other parts of electrical equipment.
  • The skills and techniques necessary to determine the nominal voltage of exposed live parts.
  • Minimum approach distances and the skills and techniques necessary to maintain those distances.
  • The proper use of special precautionary techniques, personal protective equipment, insulating and shielding materials, and insulated tools for working on or near exposed energized parts of electric equipment.
  • Recognition of electrical hazards to which the employee may be exposed and the skills and techniques necessary to control or avoid those hazards.

A note to paragraph 1910.269(a)(2)(ii) requires these topics to be covered in training for a person to be considered qualified. The bottom line is that all substation entrants must have substation entry and hazard training specific to their tasks and exposures that meets the requirements of the 1910.269(a)(2) standard.

Q: Are auxiliary outrigger pads required by OSHA for all outrigger use?

A: No, not by any rule, but the requirements for stabilizing an outrigger-supported truck make it a reasonable policy. We are familiar with an executive from a major equipment manufacturer who said the company has never been sued for a truck turnover where the truck was set up on auxiliary outrigger pads. That may or may not be true, but longtime safety history would seem to support that statement. Few investigations if any have turned up instances where a truck set up with pads or a properly constructed barrier became destabilized by an outrigger punch-through.

When OSHA’s Cranes and Derricks in Construction standard (1926 Subpart CC) was released, there were requirements for setting up and ensuring stability of the crane that created industry-wide interest in the stabilization of outriggers. The industry knew from experience that outrigger pads add stability and decrease chances of an outrigger punching through the sand and failing.

The reason is largely explained by the physics of earth’s resistance. When we press down on the earth, we don’t just compress the earth directly below our feet. The odd geometric shapes of the soil particulates produce pressure against other particulates beside and below the point of pressure. That produces a cone shape of resistance that multiplies several times over as the dimension of the pressure plate increases.

Outrigger pads used to be a lot of work when we had to build them ourselves. Now we have a variety of polymer pads that are light and large, making it relatively easy to take this fairly dependable precaution.


Jim Vaughn, CUSP

After 25 years as a transmission-distribution lineman and foreman, Jim Vaughn, CUSP, has devoted the last 24 years to safety and training. A noted author, trainer and lecturer, he is a senior consultant for the Institute for Safety in Powerline Construction. He can be reached at