Use of temporary/Portable Equipment in Class 1 Division 2 area

[richanton]

I have an area that is classified Class 1 - Div 2. It is for hazardous material storage, and the classification is only should leakage of vapors occur. If I need to run an analyzer and print a report to a printer via plugging standard 6' 120VAC cords into haz location receptacles, am I violating anything in NEC 501? I think I am unless I unplug the devices after I use them.

 

[oldfieldguy]

Most site owners have very specific procedures for 'hot work', i.e. use of equipment capable of providing an ignition source such as an arc or a thermal hotspot. In the case of my employer and in experience with several industrial facilities, this involves checking the jobsite for the presence of flammable gases or vapors using various analyzers made for that purpose. If the exposure is ongoing, then continuous monitoring might be required.


old field guy

 

[Kiribanda]

richanton,
There is no problem in using a normal cord unless an until you break it and create a spark. Therefore, what you say is correct. If you unplug the instrument
after making sure that there is no possiblity of current breaking, no worries.

 

[davidbeach]

My whole professional life revolves around very low probability, very high risk events; that said, I'd be very leery of using "normal" equipment in a classified environment. You'll get away with it most of the time. But, I always have to acknowledge that it's Mr. Murphy who pays all the bills around here, stuff will happen. Don't push it.

 

[waross]

The AHJ will be happy as long as your equipment is rated for use in a Class 1, Div 2 area.
Here's some excerpts from the Canadian Code. The US code is often similar, and this represents good practice.

18-050 Electrical equipment (see Appendix B)
(1) Where electrical equipment is required by this Section to be approved for use in hazardous locations, it shall
also be approved for the specific gas, vapour, mist, or dust that will be present.

18-056 Non-essential electrical equipment
(1) No electrical equipment shall be used in a hazardous location, unless the equipment is essential to the
processes being carried on therein.

18-070 Combustible gas detection (see Appendices B and H)
Electrical equipment suitable for non-hazardous locations shall be permitted to be installed in a Class I, Zone 2
hazardous location and electrical equipment suitable for Class I, Zone 2 hazardous locations shall be permitted
to be installed in a Class I, Zone 1 hazardous location, provided that
(a) no specific equipment suitable for the purpose is available;
(b) the equipment, during its normal operation, does not produce arcs, sparks, or hot surfaces, capable of
igniting an explosive gas atmosphere; and
(c) the location is continuously monitored by a combustible gas detection system that will
(i) activate an alarm when the gas concentration reaches 20% of the lower explosive limit;
(ii) activate ventilating equipment or other means designed to prevent the concentration of gas from
reaching the lower explosive limit when the gas concentration reaches 20% of the lower explosive
limit, where such ventilating equipment or other means is provided;
(iii) automatically de-energize the electrical equipment being protected when the gas concentration
reaches 40% of the lower explosive limit, where the ventilating equipment or other means referred
to in Item (ii) is provided;
(iv) automatically de-energize the electrical equipment being protected when the gas concentration
reaches 20% of the lower explosive limit, where the ventilating equipment or other means referred
to in Item (ii) cannot be provided; and
(v) automatically de-energize the electrical equipment being protected upon failure of the gas detection
instrument.

Rules 18-050, 18-066
It should be noted that battery-operated and self-generating equipment is not excluded from the Rules of
Section 18, regardless of the voltage involved. Examples of such equipment are flashlights, transceivers, paging
receivers, tape recorders, combustible gas detectors, vibration monitors, tachometers, battery- or voice-powered telephones, and portable test equipment that may be carried into or located within a hazardous area. Such
equipment may be eligible for approval under CAN/CSA-C22.2 No. 157 or CAN/CSA-C22.2 No. 60079-11.
Where general-purpose enclosures are used for such equipment and the Rules of this Section require the
equipment to be specifically approved for the hazardous location, the electrical equipment is required to be
approved for the location as intrinsically safe in accordance with Rule 18-066 and marked in accordance with
Rule 18-052.

Why not save the data to an SD card or USB memory and print in the comfort of an office??
Try to locate the analyzer outside the area.
Some types of HL receptacles will only accept HL cord ends. You may be able to plug in the standard cord but not be able to energize it.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[wroggent]

Anyone know if there is an NEC equivalent to "Rules 18-050, 18-066" that waross posted?

 

[Parchie]

I think it's Article 500, Hazardous Locations.