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Training Users of Aerial Lifts

Written by Jim Vaughn, CUSP on . Posted in .

Last year, Incident Prevention published an article by Altec’s Phil Doud regarding changes to the ANSI A92.2 standard regarding vehicle-mounted elevating and rotating aerial devices (see https://incident-prevention.com/blog/ansi-a92-2-2022-changes-and-training-requirements/). It is a good and timely article. In it, Mr. Doud points out that many of the training requirements in the revised 2021 edition of the standard were already expected, but the standard now captures in detail the type and content of training for aerial lift operators and supervisors of those operators.

It is time for such detailed language to be published because we have a real problem with unqualified users operating aerial lifts, especially in energized distribution applications when material-handling jibs are involved. In the past two years, I have provided litigation support to employers and one manufacturer in five civil cases involving material-handling bucket trucks. In each of those cases, I was stunned to hear how the trucks had been used. As an industry, I thought we had a pretty good grasp of the limitations of insulating aerial buckets, but apparently not. As I have consulted with manufacturers, I have found that there are many cases in which operators of aerial bucket trucks have set them on fire or pulled the buckets off the boom due to a lack of familiarity with the applications and limits of the equipment.

In the past, I have personally seen two apprentices in a bucket attempting to pull H-frame cross-braces together to install the bolted-up joiner plate by throwing a lanyard around the back of the outside brace and pulling it in with the bucket. The bucket was torn from the mounting bracket. I’ve also seen material-handling jibs shear off when operators were trying to pull up 350-MCM ACSR for dead-ending. How about pulling up 350 aluminum triplex in a side strain and shearing off the rotating gear teeth, causing whiplash injury to the operator? Yes, that’s happened, too. But probably the biggest mistake that kills operators is thinking fiberglass buckets and jibs are insulating. These occurrences did not just trip circuits – they ignited fires on the outsides of buckets and killed people.

The First Thing to Know
Here’s the first thing to know: Buckets may be constructed of fiberglass, and your testing organization may clip their voltage tester to your bucket, but buckets (platforms) are not insulating. Jibs are not insulating either, even though you will see manufacturer literature with photos of wire in jib wire holders that might make the observer think they are appropriate for energized use. If trainers, operators and supervisors read the manufacturer’s operating instructions, they will find the instructions clearly state that jibs and buckets are not considered insulating. The major manufacturers ring their booms with indicators, showing that the insulating sections of the aerial device are between the boom and the elbow at the lower boom.

In the ANSI A92.2 standard, a portion of Section 9 reads, “Aerial devices or apparatus used to lift energized lines require use of an insulating device that has been rated, tested and maintained for the appropriate line voltage to prevent energizing the boom tip.” In their aerial lift operator manuals, all of the major manufacturers clearly explain that jibs are not designed to be considered insulating for the purpose of contacting energized lines. There is a multifaceted reason for this. First, the jib itself must be dielectrically tested and meet the test standards for insulating tools. Next, maintenance of insulating fiberglass tools requires inspection, periodic testing and wiping of the tools before use. In addition, it is very difficult to maintain the minimum approach distance between the worker and the energized conductor in the jib wire holder. Readers of Incident Prevention might think that MAD does not apply since the worker is gloving out of an insulating platform. That is incorrect. MAD applies to all surfaces at a different potential than the employee if the employee is not directly working on them. So, a suspended conductor in a jib must be supported in either an extension adapter electrically rated for the voltage involved or in a strain-link wire holder suspended by a material-handler winch. And the conductor either must be held at a distance from the worker equal to the MAD or it must be covered.

The bucket itself brings up an issue similar to that of misused jibs. If you lay a hose-covered primary phase on the lip of your bucket to move it to a new location, you are contravening several standards. There is no OSHA standard that directly addresses this practice, but OSHA relies on ANSI, NESC, IEEE and other consensus standards for their own citation guidance. A conductor in a hose lying on a bucket lip puts the rubber in compression. “In compression” refers to the weight of the conductor pressing and thinning the rubber hose at the point of compression between conductor and bucket. Once in compression, the insulating value of the hose is unknown. This is the reason for “brush contact” as a limitation of use when protecting workers. The equipment is designed for brush contact; it is not designed to support load in compression or under tension.

I understand the argument that it’s all isolated and insulating and that these common practices are not unsafe. I typically explain the relative risk this way: All of the best practices captured in the consensus standards create a buffer to incidents. Those buffers, such as conductive surfaces, can become contaminated by time between tests and environmental exposures. If we continue to take shortcuts, we force those buffers to shrink until there are no buffers. That is when incidents and injuries occur. While they may not seem to be shortcuts to you, the reader, I encourage you to think about these issues.

Bucket Fires
Buckets also catch fire. I have investigated three bucket fires in civil cases. Two involved buckets that got between phases. In the third incident, a bucket ended up between a phase and hardware on a wood pole.

Fiberglass fibers are not flammable. The binders used in the resin saturate the fibers into a strong fixture. The gel coat that finishes the fiberglass structure is flammable. It is difficult to ignite a fiberglass structure, but the high heat created by an electrical arc is more than enough to begin a burn. What often occurs is that the arcing and fire will puncture hydraulic hoses under pressure, spraying a stream of flammable oil into the fiberglass fire. In all of the cases I am aware of, the bucket fires were initiated due to uncovered phases in contact with a bucket.

Part of this issue is lack of cover. The larger issue in the cases I’ve investigated was that the operators thought it was OK to make contact with an energized phase. The supervisors on the ground, too, didn’t think it was an issue. In each of the three cases, the fire was started by distribution contact that tracked across the surface of the bucket’s exterior wall. In one case, a bucket descended onto a neutral, getting it caught under the boom between the bucket and boom in the vicinity of the hydraulics. While the operator was maneuvering around to try and free up the neutral, the other side of the single-man bucket contacted one of the phases. The arcing immediately burned into the hydraulics.

Solving the Problem
So, how does the ANSI A92 family of standards help to solve this problem? OSHA has generally held that the employer is responsible for training employees in the safety-related requirements of their work. That OSHA expectation and the agency’s General Duty Clause should have prevented all of the incidents cited above. OSHA also expects the employer to ensure employees familiarize themselves with the detailed operating manuals that come with every delivered vehicle and piece of equipment. The ANSI A92 family includes A92.22, “Safe Use of Mobile Elevating Work Platforms,” and A92.24, “Training Requirements for the Use, Operation, Inspection, Testing and Maintenance of Mobile Elevating Work Platforms”; these are your guides to compliance with the OSHA standard. There are requirements for manufacturers and dealers to provide familiarization of aerial equipment delivered to the user if the user requests it (see A92.24, 6.3.3). The standard does not require dealers to have training programs but does require them to provide resources to contact training providers (see A92.24, 6.3.2). The word “familiarization” means the orientation of a qualified person for the purpose of becoming familiar with the equipment. There is no reason that an employer cannot develop their own in-house training. In-house or employer-provided training requires a competent person to guide it. The content of the training is the manufacturer’s operating and maintenance manual, meeting the requirements of A92.24, Section 7, “Training Content.” ANSI A92.24 7.3 requires hands-on or practical demonstration of a trainee’s skills.

Ultimately, the employer must provide training that includes a competency demonstration by the operator candidate.

Supervisors of workers who operate aerial platforms are also required to be trained (see A92.24, 7.5). Individuals who supervise the use of aerial devices must be trained in the proper selection of equipment; the aerial platform’s applicable rules, regulations and standards; hazards associated with the use of aerial devices; and the value and use of the manufacturer’s operating and maintenance manuals. This supervisor training rule is almost unique in industry consensus standards; few standards focus on the safety role a worker’s supervisor can play in accident prevention.

The last new training aspect of the A92.22 standard is found at 6.1.2.6, “Rescue from Height.” There is a detailed description of the various aspects of a rescue from height. The section mentions self-rescue as one of the aspects of training and planning. I do a lot of training in rescue from buckets and find that many companies fall far short of performance expectations. Self-rescue is probably the least complicated of all rescue training scenarios, but it also seems to be the least pursued.

Conclusion
All of the information in this article raises questions, particularly if you have read the entire ANSI A92 family of documents. Training, checklists and audit lists are extensive and detailed. So, does that mean you have to follow all of the A92 recommendations to be OSHA compliant? Not necessarily. But you do have to be able to defend the rigor of your aerial lift program and show how its implementation ensures every operator knows the functions, limitations and hazards of the aerial platforms they will operate. The ANSI standards respect the long heritage of expert lineworkers out there who can operate any line equipment in a competent and safe manner. Rule 6.2.5.2 of ANSI A92.22 addresses self-familiarization with new equipment by an experienced operator using the manufacturer’s operating manual. Doing so is extremely valuable because reading through the operating manual can help to prevent future bucket fires, crashes, and related injuries and fatalities that have occurred with unqualified operators.

About the Author: 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 jim@ispconline.com.