Electrical Safety

Drawings for Hazardous Locations : NS Labour and Advanced Education, Building and Equipment Safety

Electrical Bulletin 2002-01

From: David MacLeod,P.Eng., Chief Electrical Inspector
Date: Feb 18, 2002

Subject: Requirements to submit drawings for Hazardous locations

Due to the complexity of determining the various types of hazardous gases, dust and fibres used in different applications in the industry and the consequence of error the following procedure is effective April 1, 2002.

For existing hazardous areas that have been previously classified , drawings stamped by a Professional Engineer shall be submitted when the existing process is changed (i.e.: a different type of gas, dust or fibre is being used or added) or when an area is being reclassified or declassified. Additions to existing classified areas, except as noted above, do not require drawings to be submitted.

Drawings for hazardous areas shall:

  • Clearly identify the area classification as defined per the CEC for all areas in which electrical equipment is being installed .
  • Clearly identify the type of gas, dust or fibre by name. (i.e.: acetylene, propane and aluminum , coal or flour dust etc.)
  • Clearly indicate the wiring methods to be used to meet the requirements of the CEC section 18.
  • Clearly display the stamp of a Professional Engineer
  • Clearly indicate any approved deviations with documentation or methods of protection used to determine the classifications shown. Where ventilation, pressurization, interlocking or gas detection methods are used they shall be clearly identified on the drawing(s).
All new installations in which electrical equipment or wiring is installed in an area as defined in section 20 of the CEC shall also have drawings submitted for review and acceptance to the electrical inspection authority.

Drawings for areas defined under section 20 shall provide all the information as indicated above for hazardous areas drawings except that item 3 shall refer to section 20 of the CEC and item 4 is not required by the electrical inspection authority.

All drawings in both cases shall be submitted and accepted prior to any electrical work starting.

If in the opinion of the electrical inspection authority the drawings provide insufficient information or they believe the indicated classification is incorrect the electrical inspection authority may request additional information as necessary.

All electrical work shall be performed under an appropriate electrical permit, even where drawings are not required, and shall not be energized until a final inspection is performed.

Any questions may be forwarded to the Provincial Chief Electrical Inspector at 902-424-8018.