in the Chemical Laboratory Edited by NORMAN V. STEERE, School of Public Health, University of Minnesota, Minneapolis, Minn., 55455
XI. Fire-Protected Storage for Records and Chemicals Research records and flammable chemlcals are not adequately protected against fire damage in m o ~ tlaboratories and research facilities. Unprotected chemicals can provide fuel to increase the size and extent of damage of a small fire. Research notes, thesis material, unique chemicals, and financial and academic records may be imeplseeable or mare difficult to reproduce than equipment or the huilding. There are several ways of providing fireprotected storage, ranging from inexpensive methods of gaining additional minutes of protection to built-in systems and construction for providing hours of fire protection. We believe the potential for fire law in laboratories cdls ior (1) realistic evaluation of possible losses, (2) imme diate steps to minimize losses and (3) planning for systematio long-range improvements. While various innovations and ex-
in the long run Fire-Protected Storage f o r Records Fire in a university laboratory building will usually result in an influx of graduate students trying to retrieve their research
notes to avoid having to repeat a great deal of work. To avoid loss of valuable research material and interference with fire fighting operations, research safety considerations should include fire-protected storage. Ordinary desks and file cabinets provide almost no protection ior records, since wood will hum rapidly and metal will transmit enough heat in a few minutes to ignite or seriously char papers and other records. Improvement of Existing Record Storage When funds and space are limited, ordinary desks and file cabinets can be improved to provide a measure of fire-protected storage by use of special fire retardant paints. Intumescent paints foam when heated and form an insulating barrier against heat and flames. Several such paints have been tested and are listed as fire retardant coatings by Underwriters' Laboratories, Inc., 207 East Ohio St., Chicago, Illinois 60611 in their "Building Materials List" and "Bi-Monthly Supplement." Providing adequate fire protection for records will require a detailed analysis
Loborotory Fire Reports
and a comprehensive plan based on determination of the value of various records, hazards to which the records are exposed and the present protection afforded. "Standard for the Protection of Records," NFPA No. 232-1963, $I., is recommended for every research department snd organization. The publication details the need far management and protection of records, gives standards far fireresistive vaults and file r o o m and describes standards far fire-resistive safes and other
salvaging records endangered or damaged by fire. Although same large laboratories may need fire-resistive record vaults and file rooms, the discussion which fallows will be limited to the standards for record protection equipment. Record Protection Equipment Equipment should be selected which will protect records from fires of the most destructive intensity and duration which may occur. If stairwells are open, if there is no automatic fire detection or sprinkler system, and if the building is of eambustible construction, the probable maximum condition is complete destruc(Continuad on page A860) personal libraries, a master's thesis, 500 slides prepared for a doctor's thesis, two rare books printed before 1500. The school's previous 15,000-volume library was entirely destroyed ($250,000) in 1942 and in 1957 a $30,000 fire destroyed Giles Hall. None of these buildings had a sprinkler system and none had fireresistive containers to protect records."
PROlrECTlON OF RECORDS
EDITOR'SNOTE: The National Fire Protection Association has granted permission to reprint laboratory fire reports which have been published in Fire News and Fire Record Bulletin FR58-3, "Occupmcy Fire RecardLaboratories." The fire reports which appear in this column are two of fortyeight in bulletin FRR8-3, which may be obtained for fifty cents from the NFPA a t 60 Batterymarrh Street, Boston, Massachusetts 02113. The bulletin abo includes an analysis of 100 laboratory fires, a list of NFPA publications applicable to laboratories, and the titles of other occupancy fire records, including one on college dmnitories, fraternities, and sororities. The S F P A is z nonprofit technical and educational organization to promote the scienre and improve the methods of fire protedion and prevention, to obtain and circulate inf~rmationon these suhjects, and to secure the cooperation of its rnemhers and the public in establishing proper safeguards a ~ a i n sloss t of life and property by fire.
feature
"A one hundred thousand dollar piece of laboratory equipment would be easy to replace compared to the notes taken during certain experiments. Yet these notes and the valuable supplementary material, such as slides and samples, are often subjected to minimum fire protection; in fact, they are usually left on desk tops or in desk drawers which offer very little protection or none a t all. Protection of records is an exacting study which is laid out in precise, workable form in NFPA Pamphlet KO.232. By following the suggestions in NFPA No. 232, appropriate economic protection for these records can be planned."
Feb. 5, 1956, Minneapolis, $500,000
Jon. 23, 1958, Loretta, Pa., $280,000 "A fire thought to have heen of incendiary origin, was discovered a t 5:20 A.M. by an automatic fire alarm system in thiq 2story and basement wooden college laboratory-library building that had no sprinkler system. The watchman had been through the building only 20 min before. The fire spread quickly over the wooden walls and up the open stairways. By the time the distant fire departments (6-18 miles away) arrived only the neighboring buildings could he protect,ed. Destroyed along with a chemical lab, a hidogy lab, and a 45,000-volume Library, were
"A fire of unknown origin was discovered by police in a. patrol car as the flames became visible from the exterior of the laboratory building. The alarm was immediately radioed and two additional alarms were rung within the next 10 min. Fire had such a head start in this 20-year-old, 2-story wooden laboratory that only one wall and a portion of another were left standing a t the end of the fire. A 20-year-old safe of 2-hr fire-resistive construction was severely damaged in its plunge to the eellm. The important reoords it contained were damaged by water as it sat submerged in the cellar hale until sdvaged. Mast of the records in this safe were, however, still legible. All other laboratory equipment, records, and engineering designs were destroyed by the fire. There were no sprinklers, watchman, or automatic detection within this combustible wooden building."
Vol. 41, No. 11, November 1964
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A859
tion of all combustible contents and portions of the building. Record protection equipment in woodjoisted or other nonfire-resistive buildings should be rated to withstand the impact following floor collapse, as well as the fire exposure. The method described in NFPA No. 232 far selecting record protection equipment for a. fire-resistive building is based on estimating the combustible material to which thekquipment may he exposed, assuming uniform distribution, and dividing by floor area to obtain weight of combustibles per square foot. Flammble liquid weights me multiplied by two for the purpose of ttpproximsting their fuel contribution equivalent to ordinary cornbustibles. Table 5533, reproduced with NFPA permission, assumes complete burn-out of various combustible loadings in different arrangements and shows the class of equipment needed to assure record protection. Since Class E devices are less expensive than C l m D, D less than C and so on, i t can be seen from the table that reducing the quantity of combustible eantents in a laborstory and the amount exposed will reduce the cost of record protection. Replacing or fire-retardant coating of combustible desks, filing cabinets, shelving, containem, etc., will also reduce the cost of adequate record protection. The only way to be sure that record protection equipment will meet the need ior which it is purohased is to see that it bears the label of Underwriters' Labora-
A860 / Chemical Educotion
tories, Inc., or other nationally recognized testing laboratory. I n addition to initial tests on equipment which i t labels and lists, Underwriters' Laboratories, Inc., also conducts periodic examinations and Table 5533.
tests on samples selected a t random from current production and/or stock. Class D insulated filing devices listed by Underwriters' Laboratories, Inc., are effective in withstanding 8. standardized fire
Equipment for a Fire-Resistive Building
Total combustible Contents per Floor (Including any Combustible Floaring, Partitions, and Trim), Lb Per Sq F t of Floor Area
Noncombustible Deskn, Filing Cabinets, Lockers, and Other Closed Containers. Not Over 30% of Combustibles E x ~ o s e d
Noncombustible Open-Front Shelving and Other Open Containers
Less than 5 lb 5 to 10 lb
Clam E device Class D device
Class E device Class D device
10 to 15 lb
Class D device
Class C wafe or container
15 to 20 lb
Class C safe
20 to 30 lh
Class C safe or container
30 to 35 lb
Class B safe, container or 2-hr vault Class B safe, container or %hr vault Class A safe or 4 h r vault Class A safe or 4 h r vault
Class B safe, container or %hr vault Class B safe, container or 2-hr vault Class A safe or 4 h r vault
35 to 45 lb 45 to 50 lb
50 to 60 Ib
Combustible Desks, Filing Cabinets, Shelving, Containers, Etc. Class D device Class C safe or container Class B safe, container or 2-hr vault Class B safe. container or 2-hr vault Class A safe or 4 h r vault Class A safe or 4 h r vault
Class A safe or 4 h r vault
6 h r vault
6-hr vault
6 h r vault,
6-hr vault
6 h r vault with no combustible near door
of controlled extent and severity for a t least one hour, reaching 1700DF,before an interior temperature of 350DFis reached st the center of the container or its insulated compartments during the period of fire exposure or the subsequent cooling period in the furnace. Class D devices also have t o withstand a sudden heating without producing an explosion sufficient to cause an opening to their interior in a test in which the sample is inserted in a. furnace preheated to 2000'F and kept at that temperature for 30 min. In both exposures papers loosely distributed and in contact with the filing faces must come through in usable condition, capable of ordinary handling without breaking and decipherable by ordinary meam. Contents are not considered usable if they require special preparation to permit handling or are decipherable only by special photography or chemical processes. Manufacturers of Class D-1 hour insulated filing devices listed by Underwriters' Laboratories, Inc., in January, 1964, include: John D. Brush & Co., Rochester N. Y. Diehold, Inc., Canton2, Ohio Herring-Hdl-Marvin Safe Co., Div. of Diebold, Inc., Hamilton, Ohio Meilink Steel Safe Co., Toledo 6, Ohio The Mosler Safe Co., Hamilton, Ohio Murphy Mfg. Co., Louisville 2, Ky. Safe-Cabinet Div. of Remington Rand, Div. of Sperry Rand Marietta, Ohio Schwab Safe Co., Lsfayette, Ind. Shaw-Walker Co., Muskegon, Mich. Prices for Class D fles may range from approximately $200 for a. 2 drawer file to 8300 for a. 4 drawer file, while prices for similar Class C files may range from $232 to $345. Protectall Safe Corp., Hamilton, Ohio, manufactures a Class E-'/, hr insulated filine device which has ~ a s s e da. '/, hr fire testuto 1550°F and a sudden h$&g to 2000°F for 20 min. Class C insulated record containers and safes, manufactured by many of the same companies, have passed the 1 hr 1700°F fire test before the interior temperature has reached 350°F at 1 in. from walls or doors, have withstood the sudden heating to 2000°F far 30 min, and in addition have withstoad an impact due to falling 30 ft in the clear after being heated for 30 min and reheating in the inverted position for 30 min after impact without destroying the usability of papers stored inside. Other companies which manufacture Class C safes m e : Acme Visihle Records, Crozet, 1's. Gary Safe Co., Loa Angeles 21, Calif. Victor Safe & Equipment, Remington Rand Dealer Sales, Div. of Sperry Rand, North Tonawanda, N. Y. ClassIB insulated record containers, and s& are tested to withstand a 2-hr fire test to 1850°F, the sudden heating to 2000'F for 30 rnin and the 30-ft impact test with heating far 45 min and reheating far 1hr. Class A safes, made by several of the companies mentioned and by LeFehure Corp., Cedar Rapids, Iowa, are tested to withstand a 4 h r fire test to 2000DF,as well as the sudden heating test, and the impact test with 1 hr each, heating and reheating. Vol. 41, No.
I I , November 1964
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Fire Protected Storage for Chemicals Although fire will damage most chemicals or their containers, the greatest need of fire-protected storage is for chemicals which are easily ignited, difficult to extinguish or burn with great rapidity. Oreanic .. oeroxides. am comoounds. ovrophs.r>e metals, and lie~~~rn:~l,lc liquidi are smw f I I W types u i dtt!mimls w l d wed ~ w[.xr:tte>wdhre-prvteitrd su,ragt.. It seems important to recommend that chemical storage practices be reviewed from time to time and the hmards evaluated. Sodium and potassium deserve better protection than results when they are stored according to the alphabet rather than the hazard. Placing all acids together may seem to be the simplest method of s t o r a g ~ x c e p tthat 7&720/0 perchloric acid should not be next to glacial acetic, and picric acid should be in a third place. The first step toward fire-protected storage of hazardous chemicals is to reduce quantities in the laboratory t o the minimum practicable, which reduces the fire load and the amount of storage needed. We do not believe it is practicable to limit quantities in the lab to only one day's supply-but there should he an hone& effort to reduce quantities to workable minimums. While it does not seem a t all safe or workable for every laboratory to have to get all its flammable liquids each day, as some standards propose, neither is i t reasonable to aocumulate gallons of all the common solvents on open shelves. Only two gallons of one flammable solvent recently fueled a fire that caused an estimated $60,000 of damage, and the damage would have been much greater if 10 or 15 gal had been involved. The NFPA Flammable Liquid Code calls for flammable or combustible liquid containers not larger than one quart (946 cc), which can generally be a workable size limit, even in gctduate organic r e search labs. However, if a laboboratory process requires five gallons of solvent for a. single run, the solvent should not have to be in 20 quartsize bottles. Same extractions or pilot plant operations may require such large quantities of solvent that one whole day's supply will be too much to store in the lab. High shelves are unsuitable for storing bottles of combustibles because of the hazard of breakage and the more rapid build-up of heat in s. fire. Open shelves and cabinets with glass doors are not suited for storage of chemicals which are hazardous if broken open by fire-fighting hose streams. Many flammable liquids, particularly technical grade, can he used in metal containers which will not rupture under fire conditions. Safety cans approved by Factory Mutual Laboratories have an FM label and a. flash-arresting screen in can openings. Teflon gaskets should he specified in preference to leather. Manufscturers of flammable liquid safety cans include Eagle Mfg. Co., 24th & Charles Sts., Wellsburg, West Virginia; Justrite Mfg.Co., 2061 N.Sauthport Ave., Chicago, Illinois 60614; and Protectoseal Co., 1920 S. Western Ave., Chicago 8, Illinois. (Continued a page A864)
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Chemical Educafion
The Protectoseal Company makes a very broad range of safety cans suitable for laboratory use, including stainless steel safety cans suitable for reagent grade solvents, siees from pint to five gallon, special shapes for shelf storage, cam with flexible pouring spouts, and flammable waste disposal containers. Proteetoseal also makes a bottle carrier lined with polyurethane foam which has been used for holding bottles of flammable solvents and found to provide about six minutes protection from a spill fire.
Improvement of Existing Laboratory Storage for Flammable Liquids The insulating value of a wooden door prevented involvement of two gallon glass bottles of benzene in the recent $60,000 laboratory fire mentioned earlier. Existing benches and cabinets used for labor* tory storage of flammable liquids and other hamrdous chemicals can be improved by intumescent fire retardant coatings or by other means which provide effective fire insulation. Transite or asbestos board does not provide fire insulation. Although such material may withstand heat to which it is exposed, it transmits the beat rapidly by conduction.
Cabinets for Fire-Protected Storage Although one national code requires flammable liquids in laborstories to be in double w d e d metal storage cabinets, if not in safety cans or containers less than a quart, other national standards snd authorities attribute very little protection to such a cabinet. Review of the fire performance standards for records protection equipment, listed earlier, supports the view that temperatures within uninsulated metal cabinets would be likely to exceed 350°F in just afew minutes. We recommend considerstion be given to use of Underwriters' Laboratories listed insulated filing devices and record containers, for fire-protected storage of heat sensitive chemicdls and flammable liquids. The well-developed standards and the testing program for record protection equipment seem to assure that such equipment would provide a known measure of fire resistance. We believe that special standards need to be developed for chemical storage cabinets and that special tests have to be devised and evaluated so that chemical storage cabinets can be built to meet the needs for fire-protected storage. The Los Angeles Fire Department conducted some interesting tests early in 1959 to compare heat transmission of sections of various metal and wood cabinets, and adopted a standard (LAFD Standard No. 40, 1-1-60) for plywood cabinets for hazardous materials storage. A typical cross section of five kinds of metal cabinet walls was made as follows: 1. A double wall, metal structure of 18 gauge CR steel, approximately 7 in. X 10 in. with 1.5 in. air space. 2. A similar cross section was made
(Catimed on page A866) A864
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Chemical Education
with a core of V 8in. sheetrock suspended midway in the 1.5 in. air space. 3. A similar cross section was used with a core of in. Douglas Fir plywood untreated suspended in the air space. 4. Metal-walled structure insulated with 1 in. of 1 lh. density fiberglass blmket in the 1.5 in. air space. 5. Metal-walled structure insulated wit,h 1.5 in. of mineral rock wool density unknown. The wood sections were set up in a. similar manner and consisted of the following: 1. Two layers 1 in. Douglas Fir plywood, 2. One layer 1 in. Douglas Fir plywood, 3. Laminate formed by I/, in. plywood each side of I/* in. sheetrock. Each of these struotures was fastoncd to the opening of a furnace preheated to 1300' to 1450°F. A thermocouple was attached to the opposite face of the cross section mockup. The temperature and other observations were recorded. Results
Min.
5
10
15
20
Metal #1 430°F X2 150°F 130°F 310°F #5 Zill°F
500°F 180PF 140°F 430°F 433T
510PF 210°F 160'F 470'F 466OF
6SO"F 240°F 170°F
Wood #1 100T #2 120°F #3 80°F
100°F 100°F 133'F 166'F 100DF llO0F
100°F 200°F 130'F
. .. ...
Test results seemed to indicate that further testing of flammable liquid storage cabinets would be in order. Extensive tests were conducted later that year on wooden cabinets, and the results were so satisfactory that the Department meommended plywood cabinets in preference to non-insulated metal cabinets. I t should be noted that while no metal cahinet manufacturers submitted samples for the tests, the Department did a t a later date test and approve one manufacturer's metal cabinet for use in the City of Lus Angeles. The following are the Los Angeles Fire Department's specifications for the construction of Hazardous Materials Storage Cabinets as contained in the LAFD Standw d No. 40, 1-1-60. The Type A cabinet shall he used ior tho storage of dangerous chemieals. Either the Type A or the Type B cabinet may be used for tho storage of hazardous nmterisls other than dangerous chemicals (i.e., flammable and combustible liquids). Cabinets shall be constructed of plywood. The Type A cahinet shall not be Less than 2 in. thick. The Type B cahinet shall not he less than 1 in. thick. 50material shall he used having a thickness Less than 1 in. All joints shill1 he rsbhetted and shall be fastened in two directions with flsthead wood screws. (Continued on page A868) A866 / Chemical Education
All doors shdl be self-closing and equipped with substantial hinges. When more than one door is used there shall be a rahhetted overlap of not less than 1 in. Doors shall be equipped with a substantial locking or latching device. The shelves in Type A cabinets shall he of wood not less than 1 in. thick. Shelves for Type B cabinets may be of either wood or metal. The volumetric cappacity of cabinets shall not be more than 50 cu ft. The contents of all cahinets shdl be indicated by appropriate warning signs, with letters 3 in. high on contrasting bsckground. We understand that the Los Angeles Fire DeparLment standard is based on the absence of any record of fires originating within storage cabinets, and on a design philosophy of providing enough thermal insulation barrier to protect cabinet eontents until the area is untenable and persons are not present to be injured when and if the cabinet fails. Coatings of fire retardant paint on the exterior of storage cabinets would provide additional fire protection, as would incorporation of a package system for automatic extinguishment by carbon dioxide or dry chemical.
Special Rooms While outdoor locations or detached huildings are preferred for storage or handling of drums and hulk quantities of flsmmahle liquids, most laboratory buildings need to have a wellsupplied stockroom within the building. Some industrial laboratories have outdoor storage for drums of flarnmahle liquids that will not freeze, and several universities hsve separate storage buildings, more than 50 ft from main buildings, far drums and ease lots. Every laboratory building that stocks over 50 gal of flammahk or combustible liquids should have a special cutoff room to provide fire-protected st,oragefor ehemicals. Cutoff rooms for flammable and combustible liquid storage should not be below grade level in basements or subbasements because of the difficultyof providing adequate drainage, ventilation, and explosion-venting ( 1 ) . Cutoff storage roams should be located s t an exterior wall and be separated from laboratories and corridors by fire resistive eonstmotion, including walls, floors and automatic-dosing fire doors, of a t least 1L/2 hr fire resistance. If the average weight of flamm~hleand enmbustible liquids exceeds 15 psf of floor area, the minimum fire resistance of construction should be increased by s/, hr for each increase of 5 psi of flammable and cumbustible liquids
(2). The NFPA Flammable and Combustible Liquids Code (S), which may be the basis of legal regulation in some jurisdictions, specifies that inside storage rooms (or cutuff rooms) s l d hsve n fireresist,ive rating of not less than 2 hr with noncombustible walls, floors and ceilings. The code also calls for 6 in. liquid-tight. sills or ramps st openings to other rooms,
(Continued on page A870)
A868 / Chemical Education
proper ventilation, electrical wiring and equipment approved for Class I Division 2 Hazardous Locations if the room is used for flammable liquids with flajh points below 100°F and, where prsctieal, large vents to provide fire and explosion relief. Since explosions of common flammable liquid vapors under optimum mixture conditions may produce pressures in excess of 100 psi (I), the maximum practical amount of venting me. should be installed on rooms used for storage and handling of flammable liquids. Vents may be doors, windows, explasion-venting sash, roof or wall panels or other devices arranged to open st internal pressures greater thau 20 psf. Positive mechanical exhaust ventilation should be provided for cutoff rooms in which flammable liquids with flash points below 100°F are stared or transferred. Ventilation should be a t the rate of 10,000 cu f t of air far every gallon of Liquid vapori~ed,except carbon disulfide which would require 20,000. Autamstic sprinklers are the basic protection for all flsmmsble liquid occupancies (I), to extinguish or limit fire, and should be provided to back up fixed automatic extinguishing systems utilising foam, carbon dioxide or dry chemicals. Grating-covered troughs the full width of all doorways into the building may be provided instead of ramped curbs, and trapped drains should be provided from the troughs and the room to conduct to a safe outdoor discharge point the maximum sprinkler discharge in the cutoff room. Portable extinguishing equipment should also he provided in convenient locations accessible under fire conditions. Building hoses far use by trained people should be equipped with adjustable spray nozzles, and wheeled dry chemical extinguishers should be considered, particularly for facilities an upper floors or remote from fully equipped fire departments.
Special Extinguishing Systems For storage cabinets or small cutoff rooms there are available package systems of carbon dioxide and dry chemical extinguishing systems.
Literature Cited
New York, 1959, p. 41-1. (2) Factory Mutual Engineering Division, "Handbook of Industrial Lass Prevention," ~McGraw-HillBook Co., New Pork 1969, p. 2-4.
(3) Xationnl Fire Protection Association, "Flammable and Combustible Liquids Code," NFPA No. 30-1963, National Fire Protection Assoriation, Boston, 1963.
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