Citation Details

Back to citations

Section: 56.12007
Date: 01/09/2015
District: NC
Negligence: Moderate
Injury or Illness: Unlikely
Injury or illness could be expected to be: Lost Workdays or Restricted Only
Significant and Substantial: No

Condition or Practice: The extension cord plugged into the receptacle junction box showed signs of burns on the female end of the plug indicating it was being unplugged from the mobile equipment heater plug when it was still under load. The Cat 966 loader is usually plugged into the cord overnight and then unplugged the next morning before operating the loader. A miner is exposed to an electrical shock or burn type injury. The Foreman knew the cord was used to plug the pre-heater of the loader in, but had not recognized the hazard of unplugging under load, and the condition had not been reported.

Action to Terminate: Inspector said mine operator must turn off power to the outlet before plugging in or unplugging the extension cord. This could be accomplished by pushing the "test" button on a GFCI outlet, flipping the breaker switch to the off position, or using a timer that turns on the power to the cord after it is plugged in and turns off the power before the cord is unplugged.

Why this concerns you: The inspector indicated this was the first mine, out of his field office, to receive this citation which led the mine operator to believe this is a new initiative. (Inspector even used the words "guinea pig" to characterize the mine & citation.) In addition to this situation with a block heater, perhaps unplugging the refrigerator to clean behind it, then plugging it back in with a spark occurring at the outlet will probably result in a citation. Also cord plugs showing burns from arching will likely result in a citation.

Abatement Suggestions From Industry

so this means you must turn the power off at a breaker? then go disconnect the plug. if the two plugs from the Male and female ends are disconnected properly yes there will be a small arc but not an explosion or an electrocution.
- posted on 06/13/2016

From a risk/hazard perspective, can an electrician fill me in. Which is higher risk/more damaging to equipment and operators:
To properly grasp the male end of the plug and remove it carefully from 120 outlet, or go to the blade switch/breaker panel, and disconnect it there/reconnect it there repeatedly?

- posted on 01/29/2015

We have been warned against this circumstance being subject to a citation for approximately a year though no standard was cited. The crux of the argument is that the scorching demonstrates damage to an electrical conductor. Obviously you can't use GFCI outlets for block heaters so that recommendation shows the inspector's lack of knowledge.
The cited standard seems to be an overreach on the inspector's behalf.
I urge the operator to fight this citation and prevent moving from guinea pig to regulatory precedent.
- posted on 01/12/2015

This citation is inappropriate. These standards were intended for electrically powered mobile mining equipment, such as shuttle cars and continuous mining machines. They were not intended to apply to connectors for low-voltage, i.e. 110 volt, domestic power supplies.

See the first standard in this suite of several related standards:

§56.12003 Trailing cable overload protection.
Individual overload protection or short circuit protection shall be provided for the trailing cables of mobile equipment.


§56.12006 Distribution boxes.
Distribution boxes shall be provided with a disconnecting device for each branch circuit. Such disconnecting devices shall be equipped or designed in such a manner that it can be determined by visual observation when such a device is open and that the circuit is deenergized, and the distribution box shall be labeled to show which circuit each device controls.

Then the standard which is cited in the case described on the IAAP web site:

§56.12007 Junction box connection procedures.
Trailing cable and power-cable connections to junction boxes shall not be made or broken under load.

The low voltage distribution system used in the US has been deliberately designed to allow for plugs to be inserted and removed when under load. In the United Kingdom, the 240 volt outlets have an on-off switch so that the higher voltage can be turned off at the outlet prior to inserting or removing a plug.

Note also that the standard refers to “junction boxes,” not wall-mounted receptacles. Junction boxes are specifically used to allow for multiple, high voltage connections for mining equipment.

- posted on 01/12/2015

Post a Comment

We have provided a place where you can post your professional comment or add additional information regarding this citation. Before doing so, please read the following guidelines:

Be nice!
If you are angry, step back and take a breath.

Post like you are talking to someone face-to-face. Better yet, post it like your mother is going to read it.

Don't discuss anything that might be construed as restraining trade. Nothing about boycotts and we certainly don't want to read about the price of rock.

Be honest!
Keep it factual. There is absolutely no need to exaggerate; some citations are hard enough to believe as is. Mine safety is important and those who visit the site must be able to rely on posts being accurate.

We review all posts
Sorry, but all posts come to us first. We want this site to be effective, and we want you to use it. The site can only be effective if it is legal and professional. If we get something that isn't both, we won't post it. None of us want that to happen.

No Guarantees
Anyone who has been a mine safety professional for long knows what one inspector approves, another may consider a violation. As much as we would like to, we cannot guarantee any solution offered here will work for your situation. We certainly hope what others have done provides helpful ideas, but we aren't willing to bet the farm on it passing an inspection and you shouldn't either.

Your name and email will not be shown when you post your comment. We ask for these fields because it helps us identify association members and keeps spam off the website.

Your Name

Your Email

Member Of



Any comments or opinions shown on this website reflect the views and opinions of the individuals or organization who posted them and do not necessarily reflect the views of any of the parties sponsoring or supporting this website. The sponsors are not responsible for the content of any comment posted on this website.