August 2017 Q&A
Q: We are a contractor and were recently working in a manhole with live primary cables running through it. We were cited in an audit by a client’s safety team for not having our people in the manhole tied off to rescue lines. We had a tripod up and a winch ready for the three workers inside. What did we miss?
A: This question has come up occasionally, and it’s usually a matter of misunderstanding the OSHA regulations. The latest revision of the rule has modified the language, but following is the relevant regulation. Look for the phrases “safe work practices,” “safe rescue” and “enclosed space.”
Safe work practices. The employer shall ensure the use of safe work practices for entry into, and work in, enclosed spaces and for rescue of employees from such spaces.
Training. Each employee who enters an enclosed space or who serves as an attendant shall be trained in the hazards of enclosed-space entry, in enclosed-space entry procedures, and in enclosed-space rescue procedures.
Rescue equipment. Employers shall provide equipment to ensure the prompt and safe rescue of employees from the enclosed space.
This rule deals with enclosed spaces, not other spaces referenced in 29 CFR 1910.269(t), “Underground electrical installations.” Enclosed spaces are not, as many think, spaces with energized cables inside. In fact, the definition of an enclosed space has no mention of energized cables. What it does have is the single criterion for an enclosed space: Under normal conditions, it does not contain a hazardous atmosphere, but it may contain a hazardous atmosphere under abnormal conditions.
If there are energized cables in the manhole, the most likely source of a hazardous atmosphere is burning insulation created by a cable failure. The smoke produced is highly toxic and will instantly incapacitate those exposed, making self-rescue unlikely.
In 1910.269(e), the scope states that enclosed space classification only applies as long as there is no hazardous atmosphere present. If a hazardous atmosphere becomes present, the space is then classified as permit-required, and all activities in the space must follow the permit-required space rules of 1910.146(d) through (k). These include rescue requirements for hazardous environments – either being trained on and equipped with breathing and protective apparatus, or using non-entry rescue, which requires that rescue lines are attached to workers entering the space. This is the most likely reason you were cited in the audit, and the auditors were correct in their interpretation of the standard.
Q: We have received new disconnects with through-the-cover voltmeters indicating the phase-voltage conditions behind the cover. Each meter is connected to the load side of the switch. Is this voltmeter appropriate for lockout/tagout or for electricians as a means of checking for voltage prior to starting work after turning off the disconnect?
A: It is not appropriate for electricians if we are to follow the standards of NFPA 70E. The standard requires verification of the voltage testing device before and after the absence-of-voltage test is performed. You can’t do that with a permanently mounted meter. In any case, checking voltage at the disconnect is not sufficient to meet the absence-of-voltage check at the work location if it is remote to the disconnect. The voltage still has to be checked at the point of exposure. You can use a non-contact voltage detector if the user is properly checked out on the tool and the before-and-after verifications are made. Unfortunately, that still requires close access to the energized part in order to perform the check.
For non-electrical workers who are authorized to operate a disconnect, it might be appropriate to perform lockout/tagout. Mechanics or maintenance people who are not performing electrical work are not required to do an electrical check. They are only required to perform a disconnect, lockout the disconnect and then to try to start the motor from the controls. The meter might be one way of indicating the disconnect is open, but it would not relieve the operator of trying the locked-out apparatus to ensure the energy source is removed.
Q: We were reading “Train the Trainer 101: Grounding Trucks and Mobile Equipment” (https://incident-prevention.com/blog/train-the-trainer-101-grounding-trucks-and-mobile-equipment) and have a question. Let’s say that a line truck has insulated upper and lower sections; is positioned such that a line dropping wouldn’t contact the truck directly, provided a pole isn’t struck by something else altering the truck’s relative position; all lines are well-covered with blankets and hoses; and the truck is grounded to the best available ground. Is all of that sufficient to cover 1910.269(p)(4)(iii)(C) – which requires that every employee be protected from hazards that might arise from equipment contact with energized lines – so that equipotential grounding mats and barricading are not necessary?
A: According to 1910.269(p)(4)(iii)(C), “Each employee shall be protected from hazards that could arise from mechanical equipment contact with energized lines or equipment. The measures used shall ensure that employees will not be exposed to hazardous differences in electric potential. Unless the employer can demonstrate that the methods in use protect each employee from the hazards that could arise if the mechanical equipment contacts the energized line or equipment, the measures used shall include all of the following techniques …”
That “ensuring” can be a product of several conditions, including training and procedures that keep a worker clear of the truck and step-potential hazards. All the employer has to be able to do is defend them. If the employer can ensure that those alternate procedures protect workers on the ground, then equipotential mats are not required and the conditions of the rule would be met. However, if one person walks up and violates those rules, the training received and the isolation policy are moot. The equipotential mats would be required.
Q: I would like to find out if there are any mandatory standards, either from OSHA or NFPA, for the required amount of time a student must spend taking an electrical safety practices and work standards (arc flash) training course. For example, do either of these agencies require that a student must spend, say, 90 minutes learning this content?
A: There are some mandatory time requirements and other criteria for training, but they are limited to specific industries and are few and far between. An example would be powered industrial trucks (PITs), which have a requirement for materials and types of training. There are no time requirements for PIT training, just content rules. There are time and content requirements for the electrical safety portion of OSHA 10 training and for MSHA new miner training. Both of these are general safety awareness training for non-electrical workers and are not task-specific to the electrical crafts. The topics you ask about – electrical safety and arc flash – if related to the employee’s task assignments, would be delivered apart from the OSHA 10 curriculum. That training would have no particular time requirements. For such training, OSHA requires employers to ensure the employee is qualified in their safety-related tasks to protect themselves from the hazards. It is up to the employer to determine what training is required and how to provide it. The employer can engage an outside third party to deliver the training or perform it in-house using a qualified person. The answer is that there are no standards for the time period of an employee’s training on workplace hazards. The training is required to be sufficient to cover the recognition of the related hazards, safety procedures, PPE use and what to do in an emergency. There are no specific times required because all work-related exposures are not the same. OSHA does expect the training to include written and practical demonstrations to prove the effectiveness of the training.
Do you have a question regarding best practices, work procedures or other utility safety-related topics? If so, please send your inquiries directly to [email protected]. Questions submitted are reviewed and answered by the iP editorial advisory board and other subject matter experts.