Intrinsically Safe flashlights limit the energy (electrical and thermal) available for ignition in hazardous area, but it is not a safety designation. There are different guidelines and ratings you need to be aware of to make sure it is suitable for your application.
The Hazardous Area Electrical Guidelines are divided into three classes:
Class I represents flammable gases, vapours, or liquids, such as acetylene, hydrogen, ethylene, or propane. Example locations include: oil refineries, gas plants, offshore oil rig.
Class II represents combustible dust, such as grain, coal or metals. Example locations include: coal mines, grain elevators, hay storage facilities, producers of plastics, medicines, or sugar.
Class III represents ignitable fibers and flyings, such as sawdust, or machined magnesium. Example locations include: paper mills, textile mills, woodworking facilities.
Within each class designation, there are division ratings of either 1 or 2:
Division I is when a mixture of flammable gases, dusts, or vapours occurs normally or is always present.
Division II is when a mixture of flammable gases, dusts, or vapours, is potentially present. Div II locations could be adjacent to Div I locations where flammable substances might escape to due a failure in a containment system or during maintenance activities.
We hope this brief overview of the guidelines helps provide clarification in your flashlight choice.