NR-23 Fire Extinguishers Area
Estimates fire extinguishers required by floor area per Brazilian NR-23 (1 per 500 m2).
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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.
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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.