Sources of Ignition:

All known sources of ignition must be eliminated in areas that contain, or might hold, flammable gases.  This involves areas whereas gases are being manufactured or used in a few procedures and in areas whereas they are stored.

One potential source of ignition is electrical equipment.  While used or installed in hazardous locations, that equipment must be explosion-proof and properly installed.

Electrical equipment involves not only the more obvious equipment like as motors, generators, switches, motor controls, and lighting fixtures, other than also the not so obvious equipment like as alarm systems, telephones remote controls, and other communication systems.

The use of unapproved portable electric tools and equipment should be strictly prohibited in hazardous locations.  While temporary lighting is used, it must be an approved category and in excellent repair.

All probable sources of static electricity should be anticipated to avoid its buildup and discharge.  Various techniques of control might be used.  It is essential which conductive elements of a system be bonded together to eliminate the difference in potential among the parts, and the whole system grounded to eliminate the difference in potential among the ground and system.