Acid batteries are used throughout industry to provide power for work vehicles and
uninterrupted power supplies. For example: battery-powered fork-lifts are used in
warehouses; battery-powered carts are used on golf courses; telecommunications facilities
use great numbers of emergency standby battery systems to maintain service during
commercial power outages; electrical utilities also use many battery systems in their
power generation and distribution networks. Because of their ubiquity, reliability and
low-maintenance, these battery systems are often overlooked when addressing hazardous
materials in the workplace.
The typical lead-acid battery
electrolyte is approximately 60% water, and 40% sulfuric acid (CAS 7664-93-9); and traces
of lead. Analysis of electrolyte from a new battery may contain less that 1 mg/L of lead
in solution. An old, well worn battery can contain electrolyte with lead as high as 70
mg/L. Of course, lead sulfate can form as a sludge in the bottom of the battery jar.
Sulfuric acid is the highest volume
chemical produced in the world. It is used in more chemical reactions and industrial
processes than any other chemical
Sulfuric acid is not flammable by
itself, but it can cause and support a fire by reacting with other chemicals and
liberating enough heat to ignite ordinary combustibles. Sulfuric acid can also support a
fire by releasing oxygen from the sulfate ion and therefore feed oxygen to the flames. The
sulfuric acid will dissolve many metals, releasing hydrogen which is extremely flammable.
Heat generated during this chemical reaction can ignite the hydrogen, creating an
Sulfuric acid is extremely dangerous
when it contacts oxidizers and organic materials. This acid, in high concentrations, is
also a major hazard to human life. When sulfuric acid comes in contact with flesh, it
withdraws water, leaving a black charred carbon residue, in the place of living tissue.
The higher the concentration, the greater the danger. If sulfuric acid comes in contact
with large areas of human tissue, death can occur. If acid fumes are inhaled, serious lung
and bronchial damage can occur.
Here is a quote from the NFPA fire
investigation report of the Los Angeles Grand Telephone Exchange fire of March 15, 1994:
"One of the threats was sulfuric
acid (28 percent solution, similar to a car battery) that had been released from damaged
batteries. The batteries were not in diked areas so the leaking acid formed pools covering
the floor near the batteries. Since typical protective gear for structural fire fighters
is not effective against acids, injury could have resulted had fire fighters been crawling
as they approached the fire or slipped and fallen while walking through the acid
Sulfuric Acid Classification by Fire
(12.7 to 50% concentration)
The 1994 UFC classifies
sulfuric acid hazards as:
Class 1 (Appendix VI-A 22.214.171.124)
Reactive Class 1 (Appendix VI-A 2.1.9)
(Appendix VI-A 126.96.36.199)
Target Organ or System (216) (Appendix VI-A 188.8.131.52) (MSDS)
UFC use classification for the two major types of lead-acid batteries are:
(Flooded) - Use, Open System (Section 222)
Regulated (VRLA) - Use, Closed System (Section 222)
So by combining the UFC sulfuric acid
hazard classifications and the Open and Closed System Use, we can approach the maximum
exempt gallons per control area from several directions:
Maximum Sulfuric Acid Exempt Gallons
per Control Area without Sprinklers
(Table 8001.13 A&B)
THE 1994 UNIFORM FIRE CODE
The 1994 UFC treats battery rooms as
any other hazardous materials storage situation. For example, Article 80 states:
Exempt amounts shall be as specified in Section 8001.13.2 and Tables 8001.13-A through
8001.13-D. Storage, dispensing, use and handling of hazardous materials in quantities
exceeding exempt amounts shall be in accordance with Sections 8001, 8003 and 8004.
Storage, dispensing, use and handling
of hazardous materials in quantities not exceeding exempt amounts shall be in accordance
with Section 8001.
8004.2.2.5 Spill control,
drainage control and secondary containment. Rooms or areas where hazardous
material liquids are dispensed into containers exceeding a 1-gallon (3.785 L) capacity or
used in open containers or systems exceeding a 5-gallon (18.93 L) capacity shall be
provided with spill control. Secondary containment shall be provided when the capacity of
an individual container exceeds 55 gallons (208.2 L) or the aggregate capacity of multiple
containers exceeds 100 gallons (378.5 L).
control, drainage control and secondary containment. When required by other
provisions of Section 8004, spill control, drainage control and secondary containment
shall be provided in accordance with Section 8003.1.7.
8003.1.7 Spill control, drainage
control and secondary containment.
8003.1.7.1 General. Rooms,
buildings or areas used for the storage of solid and liquid hazardous materials shall be
provided with a means to control spillage and to contain or drain off spillage and
fire-protection water discharged in the storage area in accordance with Section 8003.1.7.
control. Floors shall be sloped; constructed with sumps and collection systems;
recessed a minimum of 4 inches (101.6 mm); provided with a liquid-tight raised sill to a
minimum height of 4-inches (101.6 mm) to prevent the flow of liquids to adjoining areas;
or otherwise constructed to contain a spill from the largest single container or tank.
Except for surfacing, the sill shall be constructed of noncombustible material, and the
liquid-tight seal shall be compatible with the material stored. When liquid-tight sills
are provided, they are not required at door openings which are provided with and
open-grate trench that connects to an approved drainage system.
Other limitations that seem to affect
the placement of large stationary battery systems:
Appendix VI-D Table 5B Basic
allowable building heights and basic allowable floor area for buildings one story
in height. This table limits the placement of flooded batteries to not over the third
Article II - Definitions and
Abbreviations, Section 204-C. Control Area is a building or portion of a building
within which the exempted amounts of hazardous materials are allowed to be stored,
dispensed or handled.
Requirements. Control areas shall be separated from each other by not less than a
one-hour fire-resistive occupancy separation.
The number of control areas in buildings or portions of buildings used for retail or
wholesale sales shall not exceed two. The number of control areas in buildings with other
uses shall not exceed four.
102.1 Existing Conditions.
The provisions of this code shall apply to conditions arising after the adoption thereof,
conditions not legally in existence at the adoption of this code, and to conditions which,
in the opinion of the chief, constitute a distinct hazard to life or property. See also
Appendices I-A and I-B.
103.1.2 Alternate materials
and methods. The chief, on notice to the building official, is authorized to
approve alternate materials or methods, provided that the chief finds that the proposed
design, use or operation satisfactorily complies with the intent of this code and that the
material, method of work performed or operation is, for the purpose intended, at least
equivalent to that prescribed in this code in quality, strength, effectiveness, fire
resistance, durability and safety. Approvals under the authority herein contained shall be
subject to the approval of the building official whenever the alternate material or method
involves matters regulated by the Building Code.
Article 80 places a heavy burden on
facilities with lead-acid battery systems. Since these systems were not directly addressed
by article 80, and treated as any other hazardous materials situation, a new section was
produced to provide a common-sense approach to compliance for these stationary battery
Enter Article 64
The Appendix to the 1995 Supplement to
the UFC, Analysis of the Revisions for Article 64, states:
"Requirements for the safe
installation and operation of stationary lead-acid battery systems are not contained in
the code. There are currently thousands of such systems in the field which have an
excellent safety record over many years. A growing number of authorities are applying the
requirements of Section 8003, to these installations because there is no other guidance
provided by the code. However, these systems present unique hazards which are not
adequately addressed by the existing provisions of Article 80. The proposal contains
specific and enforceable requirements for these installations which address comments
received from IFCI members and staff. The referenced standards contain detailed
requirements for all phases of stationary lead-acid battery installations."
FIRE CODE , ARTICLE 64, STATIONARY LEAD-ACID BATTERY SYSTEMS (excerpts)
Article 64 applies to stationary
lead-acid battery systems that have a total or aggregate liquid capacity of more than 100
gallons (378.5 L) in buildings with fire suppression sprinklers ( 50 gallons (189.3 L)
in non-sprinkler buildings) and are used for facility standby power, emergency power
or uninterrupted power supplies. (6401.1.)
Each rack of batteries, or group of
racks, shall be provided with a liquid-tight, 4-inch (101.6 mm) spill-control barrier
which extends at least 1-inch (25.4 mm) beyond the battery rack in all directions.
An approved method to neutralize
spilled electrolyte shall be provided. The method shall be capable of neutralizing a spill
from the largest lead-acid battery to a pH between 7.0 and 9.0. (6404.5.)
The appendix to the supplement
contains an analysis of the revisions to Article 64. It clarifies that this article
applies to all battery types, including gel-cells or VRLAs. The code writers used
the definition of "lead-acid battery" to include all "electro-chemical
cells interconnected to supply a nominal voltage of DC power."
The analysis goes on to explain that
the revision lowers the threshold rate from 100 gallons to 50 gallons to allow more
facilities to use Article 64 instead of Article 80. It also eliminates the
requirement to comply with Article 80 if any battery contains over 20 gallons of
Implementation of the UFC Article 64
offers a facility a way of compliance not only with the fire code, but also with the
intent of Environmental Protection Agency (EPA) and Occupational Safety and Health
Administration (OSHA) requirements. The potential for harm to people, equipment and the
environment can be decreased without much effort or resources. It appears that this is a
good idea whos time has come.
Fire Investigation Report,
Telephone Exchange Fire, Los Angeles, California, March 15, 1994, Prepared by Michael S.
Isner, Fire Protection Engineer, National Fire Protection Association.
Uniform Fire Code,
published by the International Fire Code Institute. Copyright © by the International
Conference of Building Officials and the Western Fire Chiefs Association.
1995 Supplement to the Uniform
Fire Code, published by the International Fire Code Institute. Copyright © by
the International Conference of Building Officials and the Western Fire Chiefs
The full text of the Uniform
Fire Code is available from:
The International Fire Code
5360 Workman Mill Road
Whittier, CA 90601-2298
Note: Supplements are excerpts and not