Workplace
Evaluation - Fixed Extinguishing Systems
Fixed fire extinguishing/suppression systems are commonly
used to protect areas containing valuable or critical
equipment such as data processing rooms, telecommunication
switches, and process control rooms. Their main function
is to quickly extinguish a developing fire and alert occupants
before extensive damage occurs by filling the protected
area with a gas or chemical extinguishing agent.
In this section we will review the employer's responsibilities
for operating, testing, and maintaining fixed extinguishing
systems that are installed to meet a particular OSHA standard
1910.160(a)(1),
or where its extinguishing agent may expose employees
to possible injury, death, or adverse health effects 1910.160(a)(2).
This section does not apply to automatic sprinkler systems
(see 1910.159)
or to systems installed to protect areas where there is
no potential for employee exposure.
This section will help you understand your requirements
under the fixed extinguishing system standard by addressing
the following issues: |
|
 |
 |
| Does
the "Fire Extinguishing System" standard apply
to me? |
OSHA's fixed
extinguishing systems standard applies to all employers
who have a fixed extinguishing system installed
to meet a particular OSHA standard, with the exception
of automatic sprinkler systems that are covered
by 1910.159.
This standard also
contains specific provisions for any fixed system,
regardless of why it was installed, that may expose
employees to possible injury, death, or adverse
health consequences caused by the extinguishing
agent. These systems are only subject to the requirements
of paragraphs (b)(4)
through (b)(7)
and (c)
of this standard.
|
|
 |
Note: Systems
installed to protect areas where there is no potential
for employee exposure to the extinguishing agent are exempted
from the requirements of this standard.
|
| System
Design and Application |
A fire extinguishing
systems is an engineered set of components that
work together to quickly detect a fire, alert
occupants, and extinguish the fire before extensive
damage can occur. All system components must be:
- Designed and approved for use on the specific
fire hazards they are expected to control
or extinguish. 1910.160(b)(1)
- Protected against corrosion or either made
or coated with a non-corrosive material if
it may be exposed to a corrosive environment.
1910.160(b)(12)
- Designed for the climate and temperature
extremes they will be exposed to. 1910.160(b)(14)
Typical elements and components
include: |
Note: Use
your mouse to explore the picture above. Click
on any number to go to that component's requirements.
|
Discharge
Nozzles A discharge
nozzle is a device designed to release the extinguishing
agent at a specific rate and pattern to quickly
extinguish a fire. Discharge nozzles must be suitable
for the fire it is intended to extinguish. 1910.160(b)(1)
The nozzle pictured is designed for total flooding
applications. Its bell shape and multiple small
discharge openings will create a widely dispersed
and diffused discharge pattern to quickly flood
an enclosed area with an extinguishing agent.
This type of nozzle is common in paint spray booths,
flammable liquid storage rooms or other similar
areas.
Nozzles designed for local application usually
consist of a cylindrical body with a straight
unobstructed center opening. This type of nozzle
produces a small discharge pattern that directs
the agent toward a local application such as paint
dip tanks, quench tanks or areas where a flammable
liquid spill may occur. |
 |
Piping
The piping network is designed to properly distribute
the extinguishing agent to the protected areas.
All fire protection systems must have pipes and
fittings that are suitable for the expected temperature
extremes with good corrosion resistance properties.
|
 |
Control
Panel
The
control panel monitors and integrates all components
together and controls the audible and visual alarms
and discharge functions. When an automatic or
manual device is activated it sends a signal to
the control panel where, depending on the type
of system and hazards, can be programmed to:
- Activate a pre-discharge alarm
- Initiate agent release
- Shutdown ventilation systems
- Shutdown machinery or equipment
- Activate visual & audible fire alarms
- Notify emergency response personnel
|
 |
Discharge
Alarm or Signaling Devices
Each
area protected by a fixed extinguishing system
must have a distinctive alarm or signal which
complies with 1910.165
to alert occupants that the system is discharging.
These alarms must be able to be heard or seen
above ambient noise or light levels, unless the
discharge is immediately recognizable. 1910.160(b)(3)
If the alarm or signaling device is used on a
total flooding system, it must also:
- Alarm before the system discharges, to give
employees sufficient time to safely exit the
space. 1910.160(c)(3)
- Be connected to an approved fire detection
device that automatically activates the pre-discharge
alarm prior to the system discharge. 1910.160(c)(4)
- Be addressed in an emergency action plan
in accordance with 1910.38
for each area that is protected.
Note: Areas protected
by a total flooding system where employees
cannot enter during or after the system's
operation are exempt from the requirements
of paragraph (c) of this section. 1910.160(c)(2)
|
 |
Warning
Signs and Safeguards
Warning
signs must be posted to warn employees in advance
about the hazards associated with the extinguishing
agent. Hazard warning or caution signs must be
posted at the entrance to and inside of areas
protected by fixed extinguishing systems which
use agents in concentrations known to be hazardous
to employee safety and health. 1910.160(b)(5)
Recommended guidelines for posting:
- To avoid confusion, keep hazard warning
signs consistent by using standardized patterns,
phrases, colors, shapes and pictures.
- Wording on signs should be concise, easy
to read, and contain sufficient information
that is easily understood.
- Warning signs must be in English and should
also be posted in the native language spoken
by the employees.
In addition to warning signs,
the employer must also provide effective safeguards
to warn employees when the atmosphere of a protected
area remains hazardous to their safety or health
as a result of a system discharged. 1910.160(b)(4)
|
 |
Automatic
Fire Detectors
Automatic
detection devices sense the smoke, heat, or flames
from a fire and initiate an alarm. All automatic
detection equipment must be approved, installed
and maintained in accordance with 1910.164.
Automatic detection devices used on a total flooding
system must:
- Automatically activate the pre-discharge
alarm before the system discharges to give
employees time to safely exit from the protected
area. 1910.160(c)(4)
Note: Areas protected
by a total flooding system where employees
cannot enter during or after the system's
operation are exempt from the requirements
of paragraph (c) of this section. 1910.160(c)(2)
|
 |
Manual
Discharge Station
A manual discharge station is a device usually
mounted on a wall near the emergency exit(s) which
will automatically sound an alarm and release
the extinguishing agent. If your workplace is
equipped with a fixed suppressant system, there
must be at least one manual station for each protected
area. 1910.160(b)(15)
Pull Station Guidelines:
- Properly mark and/or label pull stations
and other activation devices to indicate their
function and the potential hazard to personnel.
1910.160(b)(16)
- Pull stations must be clearly visible (not
blocked or covered) and located near exits
or escape routes.
- Operating instructions should be posted
at each station.
- Employees should be trained to know when,
where, and how to use pull stations.
- If possible, determine if someone is in
the area and get them out before using a manual
discharge station.
|
 |
Extinguishing
Agent Storage Containers
Storage
containers hold the extinguishing agent until
it is needed and can be high or low pressure cylinders
or tanks. These containers can be used to hold
specialized fire suppression agents like carbon
dioxide or halon to protect special work areas,
such as computer rooms, chemical storage, or similar
areas.
Storage Container Requirements:
- The weight and pressure of refillable containers
must be checked at least semi-annually. If
the container shows a loss in net content
or weight of more than 5 percent, or a loss
in pressure of more than 10 percent, it must
be maintained. 1910.160(b)(7)
- Factory charged non-refillable containers
that have no means of pressure indication
must be weighed at least semiannually If the
container shows a loss in net content or weight
of more than 5 percent it must be replaced.
1910.160(b)(8)
- Inspection and maintenance dates must be
recorded and kept until the container is checked
again or for the life of the container, whichever
is less.
1910.160(b)(9)
- Avoid using chlorobromomethane or carbon
tetrachloride as an extinguishing agent where
employees may be exposed.
1910.160(b)(11)
|
 |
|
| Operation,
Maintenance, and Testing |
Automatic fire suppression systems,
particularly the total flooding variety, must be operated
properly and regularly maintained and tested to guarantee
worker safety and system effectiveness. To ensure your
fire extinguishing system will perform as expected in
the event of a fire, you are required to:
- Inspect each system annually, and operate and maintain
them in a working condition, making sure they are
always turned on, except during repairs or maintenance.
1910.160(b)(6)
- Notify employees and establish measures to guarantee
their safety if a fixed extinguishing system becomes
inoperable. Any defects or impairments must be fixed
by trained personnel. 1910.160(b)(2)
- Ensure that the weight and pressure of refillable
containers is checked at least semiannually. If the
container shows a loss in net content, weight, or
pressure, it must be subjected to maintenance.
1910.160(b)(7)
- Assure that factory charged non-refillable containers
that have no means of pressure indication are weighed
at least semiannually The container must be replaced
if it shows a loss in net weight.
1910.160(b)(8)
- Assure that inspection and maintenance dates are
recorded and kept until the container is checked again
or for the life of the container, whichever is less.
1910.160(b)(9)
- Annually train employees who inspect, maintain,
operate, or fix extinguishing systems.
1910.160(b)(10)
- Train all employees with respect to the type of
systems installed in the workplace, the hazards involved,
proper activation in case of emergency, and the correct
response to audible and visual pre-discharge alarms.
Provide training for non-English speaking employees
in languages understood by the affected employees
and other individuals that may be exposed to the hazard.
- Provide and assure the use of personal protective
equipment (PPE) for rescuing employees trapped in
areas that have become hazardous due to an agent discharge.
1910.160(b)(17)
|
| Total
Flooding Applications |
Total Flooding Applications consist
of protecting an enclosed space by flooding it with a
gas, such as carbon dioxide or halon. This method is used
to protect electrical equipment and other types of deep-seated
smoldering fires that may re-ignite after the flame has
been extinguished. Because these systems can create an
oxygen deficit or toxic atmosphere they deserve special
attention.
The following special provision apply to all fixed suppression
systems used for total flooding applications:
- There must be an emergency action plan in accordance
with
1910.38 to provide for the safe evacuation of
employees from within each area protected by a total
flooding system. 1910.160(c)(1)
Systems installed in areas where employees cannot
enter during or after the system's operation are exempt
from the requirements of this section.
1910.160(c)(2)
- Each area protected must be equipped with a pre-discharge
alarm that complies with 1910.165
that is capable of being perceived above light or
noise levels, and which gives employees time to safely
exit the area before discharge.
1910.160(c)(3)
- Install and connect fire detection devices to pre-discharge
alarm systems which automatically activate total flooding
systems.
1910.160(c)(4)
- Signs must be posted in and at the entrance to areas
protected by total flooding fire suppression systems
which use agents that are a serious health hazard,
such as carbon dioxide, Halon 1211, etc.
- Have personal protective equipment (such as 5-minute
"escape packs") available and ready for
rescuing employees trapped in areas that may become
hazardous due to an agent discharge.
1910.160(b)(17)
Safety and Health Hazards
The Material Safety Data Sheet
for each extinguishing agent should be available in the
workplace. It is important that employees know the potential
hazards of the extinguishing agents they may be exposed
to and how to protect themselves. Additionally, employees
who are likely to enter such areas should receive a basic
level of instruction into the operating principles of
the system to include alarms and related hazards, as well
as evacuation procedures. The two most common extinguishing
agents used for total flooding applications are carbon
dioxide and halon.
Carbon Dioxide Carbon dioxide,
under normal conditions, is a colorless, odorless, electrically
nonconductive gas that is approximately 1.5 times heavier
than air. It will not disturb live electrical components,
is non-corrosive, and leaves no residue to clean up.
Specific hazards include:
- Asphyxiation - Exposure to high concentrations of
CO2 gas may create an oxygen-deficient atmosphere.
- Cold Temperature - Direct contact with the vaporizing
liquid during discharge can cause frostbite burns
to the skin.
Halon Systems
Halon is a bromo freon that works
by replacing oxygen, thus creating an oxygen-deficient
atmosphere. This can be very dangerous to employees. The
reaction products of halon on hot surfaces may result
in the release of toxic substances and carcinogens. These
areas should be clearly labeled as follows:
Specific halon hazards
include:
- Asphyxiation - Exposure to high concentrations of
halon can create an oxygen-deficient atmosphere.
- Cold Temperature - Direct contact with the vaporizing
liquid during discharge can cause frostbite burns
to the skin.
- Central Nervous System (CNS) - Inhaling high concentrations
of halon gas can cause dizziness, tingling in extremities
and, in severe cases, unconsciousness.
- Cardiovascular Effect - In some people, exposure
to halon can cause an increased sensitivity of the
heart to adrenaline resulting in irregular heartbeats
and, in severe cases, heart attack.
- When halon is exposed to temperatures above 900
degrees F. it could break down and create high concentrations
of toxic gases.
|
|
Back to Top 
www.osha.gov
