NR-23 Fire Extinguishers Area

NR-23: Fire Extinguishers per Built Area

NR-23 (Fire Protection), read alongside the technical instructions issued by each state fire department (such as CBM-SP IT-21), tells you the minimum count of portable extinguishers for a given built area. The math is N = ceil(A / A_max), and A_max hinges on the fire load: low risk = 500 m², medium risk = 250 m² and high risk = 100 m² per extinguisher.

When mounting them, keep the handle between 0.10 m and 1.60 m off the floor, mark each spot with a photoluminescent plate, and leave nothing blocking access. The unit you pick depends on the fire class: A (solids), B (flammable liquids), C (energised electrical equipment), D (combustible metals) and K (cooking oils and fats in commercial kitchens).

Applications

Safety engineers use it to put together the AVCB/CLCB report (Auto de Vistoria do Corpo de Bombeiros), facility managers use it to schedule periodic inspections, and architects use it while laying out a floor plan. The rule of thumb for layout: the walk from any point to an extinguisher stays under 20 m for class A and 15 m for class B.

FAQ

How often must extinguishers be inspected? The building staff do a monthly visual check, and a company accredited by INMETRO handles the annual recharge — that recharge happens whether or not anyone has fired the extinguisher.

Which extinguisher works for an electrical panel? Reach for a class C extinguisher, usually CO&sub2; or dry chemical powder (ABC). Water and foam are off the table here, since both conduct electricity.

Is a class K extinguisher mandatory in restaurants? Yes. In a commercial kitchen running deep fryers, IT-21 of CBM-SP wants at least one class K unit near the cooking line, on top of the usual ABC.