Wyoming Administrative Code
Agency 053 - Workforce Services, Department of
Sub-Agency 0011 - OSHA - Oil & Gas Well Drilling
Chapter 6 - FACILITIES
Section 6-8 - Area Classifications, Facilities and Electrical Equipment

Universal Citation: WY Code of Rules 6-8

Current through September 21, 2024

(a) Area Classifications. Areas on gas and oil drilling rigs are classified as Zones I, II and III. These zones classify the area of the facilities as well as the classification for electrical equipment.

(i) Zone I includes a radial distance within six (6) feet of the shale shaker.
(A) When the shale shaker is enclosed so as not to provide adequate ventilation, the area within the enclosure shall be classified as Zone I.

(ii) Zone II areas include:
(A) Areas within six (6) feet horizontally and ten (10) feet vertically of the well bore;

(B) confined space under the drilling floor;

(C) areas within six (6) feet of the mud tanks;

(D) where the mud tanks are closed in with walls, the complete area of the enclosure.

(E) CBMNG Drilling Rigs will not operate their running lights, tail lights, or other vehicle lights, or other non-explosion proof lights while drilling the well. Once the well is capped with a wellhead, rig lights can be operated.

(iii) Zone in areas are those other areas of the well site not identified as Zones I or II above.

(b) Electrical Equipment.

(i) Zone I electrical equipment shall be a follows:
(A) Motors - three-phase totally enclosed fan cooled (TEFC) induction-type or explosion-proof

(B) Flexible cords - type SO, ST, STO, Locomotive Cable, or equivalent.

(C) Switches, circuit breakers, motor controllers and fuses - NEMA type 7-9 (explosion-proof).

(D) Plugs and receptacles - totally enclosed, gasketted and with threaded hubs (commonly referred to as "vapor proof).

(E) Lighting - not permitted within Zone I unless explosion-proof

(ii) Zone II electrical equipment shall be as follows:
(A) Motors - TEFC (totally enclosed, fan cooled) or equivalent.

(B) Flexible cords - type SO, ST, STO, Locomotive Cable, or equivalent.

(C) All other electrical equipment - totally enclosed, gasketted and with threaded hubs (commonly referred to as "vapor-proof).

(iii) Zone III electrical equipment, wiring, fixtures and cords shall be installed and used in accordance with the State of Wyoming Safety 1910 - General Rules and Regulations, Subpart S.

(iv) Direct current (DC) rotary, drawworks and catworks shall have an enclosed cooling system or be purged with air from a safe source.

FIGURE 6-2

Click to View Image

NOTE: When deciding whether to use "explosion-proof" or "TEFC" motors in Zone I, consideration shall be given to the greatest hazard. An explosion-proof piece of equipment will protect against explosion, but does not protect against electrical shock in a damp atmosphere. "TEFC" motors do not protect against explosion, but eliminate potential electrical shock in a damp or wet atmosphere.

(c) Facilities and Equipment.

(i) An exhaust pipe from any ground level internal combustion engine, located within seventy-five (75) feet of any well bore, process vessel, oil storage tank or other source of ignitable vapor, shall be so constructed that any emission of flame along its length or at its end is prevented.

(ii) Emergency shut-down device (s) that will close off the combustion air shall be properly installed and identified on all diesel engines that are an integral part of the drilling rig or are operated as a stationary or mobile engine of a drilling rig within the radius of the rig anchors or within seventy five (75) feet of the well bore, whichever is greater.

(iii) Stoves with open flame and any open flames for heating purposes shall not be permitted within seventy five (75) feet of the well bore, unless a written hot work permit is implemented.

(iv) Welding, cutting, brazing or the use of an open flame or a non-explosion proof heater within seventy-five (75) feet of the well bore shall require a written hot work permit. The hot work permit must adequately address the requirements listed in (A), (B), and (C) below and be maintained at the job site while applicable work is in process.
(A) Pre-Work Stage Communication Meeting
(1) Simultaneous operations.

(2) Air/gas testing with LEL monitor

(3) Equipment isolation

(4) Equipment preparation

(5) Identification of hazards

(6) Emergency procedures

(B) Work-In-Progress Stage:
(1) Air/gas testing with LEL monitor

(2) Personal protective equipment requirements

(3) Fire watch

(4) Special procedures/precautions

(C) Return to Service Stage:
(1) Authorization and turnover signatures

(2) Posting of permit

(v) Each CBMNG drilling location shall have a Lower Explosive Limit monitor located at the equipment operator's control panel at all times. This monitor will measure the LEL and alarm at 10% of the LEL. The monitor shall be calibrated to the manufacturer's specifications.

(vi) Generators, motors and lighting.
(A) Engine driven light plants shall be located at least seventy-five (75) feet from well bore unless properly protected to prevent source of ignition.

(B) Light plant generators shall have an adequate overload safety device.

(C) Vehicle lights shall not be used for lighting of rig operations in lieu of rig lights except in emergency.

(D) All light cords and plug-ins shall be kept in good condition.

(E) Rig lights shall be of an approved type for the area in which they are located. (See Section 8.(b).)

(F) Lamps and reflectors shall be cleaned frequently.

(G) The rays of the light shall be directed toward the objects to be illuminated, and away from the eyes of the workmen.

Disclaimer: These regulations may not be the most recent version. Wyoming may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
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