Good Morning. This is a question that often comes up in museum storage design as the selection can depend on the type of collections being stored. NFPA 10 and the local fire codes provide general guidance on the number and type of fire extinguishers. I don't have a definitive answer, and defer to your fire protection engineer. Below are some resources that evaluate and provide guidance on fire extinguishers for museum collections. Let me know if you have questions.
NARA 1571S, Architectural and Design Standards for Presidential Libraries (2018) - 3.67.10: Follow requirements of NFPA 10, the extinguishers must be in recessed cabinets, and that water extinguishers must be provided in "critical holdings areas."
Conclusions included:
- None of the extinguisher agents left the samples entirely damage free. All of them impacted at least some of the materials in the test group in some manner.
- Due to the degree to which the ABC powder spreads, the process of clean up after an intentional, accidental or malicious deployment is compounded.
- One additional caveat is important to mention. Although, individual results may appear alarming, it is important to remember that, for most extinguishing agents the degree to which the agent spread, as evidenced by the impact seen on the indirect arrays, was limited. Additionally, it is important to remember that in an incipient fire situation, not using an extinguisher is likely to have more damaging repercussions than using an available extinguisher, even if it is not the ideal type.
Manually operated portable fire extinguishers (PFEs or "fire extinguishers") are often the first line of defense when a fire breaks out in a building. PFEs supplement automatic fire protection. Annual training to operate a PFE is required for all staff. When installed in a building, properly maintained, and in the hands of trained staff, PFEs may stop a fire before it gets out of control. Fire extinguishers must comply with NFPA 10: Standard for Portable Fire Extinguishers.
There are many different types of fire extinguishers available, including (in alphabetical order):
ABC multipurpose dry chemical extinguishers use a fine chemical powder.
Carbon Dioxide (CO2) extinguishers used pressurized CO2 gas.
Clean agent extinguishers use a pressurized gas or liquid.
14. Portable fire extinguisher selection for structures housing collections
Water extinguishers use a stream of water.
Water mist extinguishers use a spray of water of smaller particle
size than a water extinguisher.
Note: Purple K and MonnexTM dry chemical extinguishers can cause severe damage to objects, and should not be used in structures housing collections.
Each type of PFE has advantages and disadvantages as described in
Figure 9.8: Comparison of Selected Portable Fire Extinguishers for Museum Objects. A combination of different PFE types may be necessary. Consult with the PSFC, AHJ or RSFM, regional curator, and a conservator to determine the type(s) of PFE best suited to each structure housing collections.
Consider the following variables when selecting fire extinguishers:
Type of materials in the collection: Some materials, such as metals and composites, may be more susceptible to damage from certain fire extinguishers than others.
Containerization of objects: Objects in sealed steel cabinets or mobile carriages in storage and on exhibit in cases or vitrines are more protected than those in open storage or display.
Impact of extinguishing agent on objects: The chemical composition of non-water PFEs may damage objects, as can the high pressure of non-mist water PFEs.
Installation and placement of fire extinguishers depends on various factors, including type of occupancy, hazards present in the building, square footage, and building layout. Ensure extinguishers are properly spaced in a building and installed along regular routes and exits so employees can access them when needed.
Note: Many museums use water mist extinguishers in collections areas, unless there are specific hazards such as flammable liquids that require other types of extinguishers.
Comparison of Selected Portable Fire Extinguishers for Museum Objects* (In alphabetical order) |
Extinguisher Description Advantages Disadvantages Type |
| Multi-purpose dry chemical extinguisher Extinguishing agent is a fine powder Used on Class† A, B, and C fires | − Easytouse
− More effective at preventing soot damage than other PFEs | − Can cause chemical damage to metals and composite objects − Deposits of powder can cause permanent damage if not cleaned immediately − Spray covers a wider area than other PFEs − Chemical extinguishing agent may irritate skin and eyes or pose respiratory problems
|
| Uses pressurized CO2 gas to displace oxygen from a fire Used on Class B and C fires Widely used in electrical rooms and computer rooms | − Easytouse
− Does not leave a residue | − Cannot be used on Class A fires, so has limited museum applicability − Can pose health issue if used in a contained space without respiratory protection
|
| Pressurized liquid or gas extinguisher Used on Class A, B, and C fires | − Easytouse
− More contained spray than ABC PFEs | − Can cause significant physical/toppling damage to freestanding objects − Can drive soot into organic objects − Can cause adhesives to swell and ink to bleed − Can pose a health issue if used in a very small contained space
|
| Uses a stream of water (tap, deionized, or distilled) to extinguish fire Used on Class A fires | − Easytouse − Does not cause chemical damage to objects − Extinguishers using distilled or deionized water aid in salvaging collections wetted during a fire
| − Can cause significant physical/toppling damage to freestanding objects − Can cause water damage to freestanding collections and structures housing collections − Can drive soot into organic objects − Can cause adhesives to swell and ink to bleed − Cannot be used on Class B and C fires
|
| Uses a fine mist of water (deionized or distilled) to extinguish fire Pressurized using nitrogen Used on Class A and C fires Widely used in museum exhibit and storage areas and archives | − Easytouse − Does not cause chemical damage to objects − Lowestriskofphysical/toppling damage to freestanding objects − Extinguishers using distilled or deionized water aid in salvaging collections wetted during a fire − More contained spray than ABC PFEs
| − Can cause water damage to freestanding collections and structures housing collections − Can drive soot into organic objects − Can cause adhesives to swell and ink to bleed − Heavier than chemical extinguishers − Cannot be used on Class B fires
|
*This table incorporates information from NFPA 10 and OSHA, "Portable Fire Extinguishers: Types of Fire Extinguishers." †Fire Class Definitions from NFPA 10: Standard for Portable Fire Extinguishers:
Class A fires involve ordinary combustible materials, such as wood, cloth, paper, rubber, and many plastics.
Class B fires involve flammable liquids, combustible liquids, petroleum greases, tars, oils, oil-based paints, solvents, lacquers, alcohols, and flammable gases.
Class C fires involve energized electrical equipment. |
MICHELE F. PACIFICO
Archival Facilities Consultant
PO Box 1490, Jackson, WY 83001
301-908-8720