In UL ratings, what does the B:C rating indicate?

The B:C rating in UL ratings indicates the effectiveness of a fire extinguisher against specific classes of fires, primarily involving flammable liquids and gases. The letter "B" denotes its suitability for extinguishing fires involving flammable liquids, while "C" signifies that it is safe to use on fires involving electrical equipment.

The number associated with the rating (if present) represents the square footage that the extinguisher can effectively cover in extinguishing a Class B fire. For example, a rating of 40B would suggest that the extinguisher can effectively handle a fire covering up to 40 square feet of flammable liquid.

This rating system helps users understand both the types of fires that the extinguisher can combat and the relative effectiveness and coverage area, allowing for better preparedness in situations involving flammable materials. The other options do not accurately reflect the meaning of the B:C rating, which specifically addresses the type of fire for which the extinguisher is rated and its capacity to handle it within a certain area.