Fire extinguishers are designed for a variety of fire situations and use various materials for fire suppression. When procuring extinguishers, it is important to identify the type needed. Classifications vary according to source of extinguisher. The following table lists the different classifications by geographic area:
|Class A||Class A||Class A||Ordinary combustibles|
|Class B||Class B||Class B||Flammable liquids|
|Class C||Class C||Flammable gases|
|Class C||UNCLASSIFIED||Class E||Electrical equipment|
|Class D||Class D||Class D||Combustible metals|
|Class K||Class||Class F||Cooking oil or fat|
The details given below use the US classification – adjust accordingly for the classification of your supplier.
Extinguishers will list the type or types of fires it is designed for, along with a preceding number to indicate the strength of its extinguishing capacity for each type of fire – for example, US 1-A:10-B:C indicates a much higher capacity for flammable liquids and gases than for ordinary combustibles. (The exception is US Class C/Australian/Asian Call E – these merely indicate safe to use on electrical equipment and does not have an accompanying quantifier). The high the number, the more powerful the extinguishing power.
Dry powder or dry chemical is the most all-purpose of extinguishers, providing coverage for most fir applications. However, they are not safe to use on cooking oil/fat fires – wet chemicals should be used for kitchen areas. Extinguishers should be purchased according to their expected use:
|Office||Dry chemical, high A rating, C|
|Garage, vehicle area, generator room||Dry chemical, High B rating, C, D|
|Guest house (except kitchen)||Dry chemical, High A rating|
|Kitchen||Wet chemical, High K rating|
|Warehouse||Dry chemical, High A, High B rating|
All extinguishers should be a minimum of ten pounds.
Procurement location: These should be procured locally if a reputable source can be identified and certification/inspection mechanism is in place.