Fire Extinguishers in an ASC

Q: We have a 1400 square foot ambulatory surgical center (ASC). In the plans there are only 5 Fire Extinguishers throughout the facility. I looked at 2012 Life Safety Code and the referenced NFPA 10-2010 but still not sure. What are the locations and how many fire extinguishers should be in this 3 operating room 1400 square foot ASC?

A: The placement of portable fire extinguishers is determined on the length of travel distance to get to a fire extinguisher…. It is not determined by the total square footage of the facility. According to NFPA 10-2010, the maximum travel distance to get to a fire extinguisher is dependent on the classification of the fire extinguisher, the capacity of the fire extinguisher, and the potential level of hazard from the fire.

Class A fire extinguishers are for normal combustibles, such as paper, wood, plastic and linens. The maximum travel distance to get to a Class A extinguisher is 75 feet for all capacities of Class A extinguishers, and all potential levels of hazard from the fire. That means you need a Class A extinguisher within 75 feet of all paper, wood, plastic and/or linen. Since paper, wood, plastic and linen are nearly everywhere in a healthcare facility, you will need a Class A fire extinguisher within 75 feet of everywhere inside the facility.

Class B fire extinguishers are for flammable liquids, such as alcohol, alcohol-based hand-rub (ABHR) solution, and xylene. The maximum travel distance to get to a Class B extinguisher is either 30 feet or 50 feet, depending on the capacity of the Class B fire extinguisher, and the level of hazard of the potential flammable liquid fire. The capacity of a Class B extinguisher is pre-determined by the manufacturer, and is identified on the extinguisher label. Usually, it is determined by the ability of the extinguisher to extinguish a fire, so the quantity of the product in the extinguisher is a factor. According to Table 6.3.1.1 of NFPA 10-2010, where the level of the potential hazard is low, a 5-B extinguisher is only permitted a 30-foot travel distance, but a 10-B extinguisher is permitted a 50-foot travel distance. Similarly, if the level of potential hazard is moderate, then a 10-B extinguisher is permitted a 30-foot travel distance, and a 20-B extinguisher is permitted a 50-foot travel distance.

Class C fire extinguishers are for electrical fires. An electrical fire is started by electricity, but the actual substance that burns is either Class A (normal combustibles) or Class B (flammable liquids). Therefore, where potential electrical fires are expected, then a Class C extinguisher is needed, based on the maximum travel distance to get to the extinguisher on either Class A or Class B standards.

Class D fire extinguishers are for combustible metals such as magnesium, zirconium, and potassium, which a typical healthcare facility does not have. Therefore, Class D extinguishers are not required if you do not have any of the combustible metals.

Class K extinguishers are for fires from cooking appliances that involve combustible cooking media (vegetable or animal oils and fats). These are found in kitchens and the maximum travel distance to get to a Class K extinguisher is 30 feet.

The determination of the level of hazard for a Class B potential fire is subjective and could vary depending on the surveyor and authority having jurisdiction (AHJ). For a healthcare facility, a low level of hazard would be areas where individual (or low quantities) of ABHR dispensers or bottles are located, and low levels of alcohol or xylene are located. A potential hazard of flammable liquids is moderate where larger quantities of flammable liquids are stored. But be careful: Based on the information in NFPA 10-2010, you would need Class B extinguishers with a 10-B rating with a maximum travel distance of 50 feet to cover potential fires from ABHR dispensers. This is often overlooked by designers when they are placing portable fire extinguishers in new facilities. Instead of the usual 75 maximum travel distance to get to a Class A extinguisher, you will need to place the Class B extinguishers with a maximum 50-foot travel distance to cover potential fires from ABHR dispensers.

There are fire extinguishers that have the rating to fight Class A, Class B, and Class C fires all in one extinguisher. These are typically ABC dry powder extinguishers, but there are other media types, such as clean agent extinguishers that can achieve an ABC rating. But dry powder extinguishers are not desirable in operating rooms where the possibility of infection is high if the dry powder extinguisher is activated. Therefore, many healthcare facilities rely on water-mist Class A:C extinguishers and a carbon dioxide (CO2) Class B inside the operating room. But you would have to make sure the water-mist extinguishers are charged with distilled water and nitrogen to prevent the growth of pathogens.

Other healthcare facilities do not use water-mist extinguishers in the operating room and rely on the sterile water in a bowl in the sterile field to extinguish any Class A fires that may occur. They then find Class B:C extinguishers to cover Class B and Class C potential fires. Keep in mind, there is no requirement that portable fire extinguishers have to be located inside each operating room. The fire extinguishers just have to be located within the maximum travel distance permitted for each classification of extinguisher, capacity of the extinguisher, and the level of hazard for the potential fire. But be careful: Some operating rooms are rather large, and it might be more than 30 feet to travel from the far corner of the operating room, to the Class B extinguisher in the hallway.

Class K extinguishers are required in kitchens, and the maximum travel distance to get to a Class K extinguisher is 30 feet. A placard needs to be installed above the Class K extinguisher that informs the staff to activate the kitchen hood suppression system first, before using the Class K extinguisher.