Inspection, Testing and Maintenance
of Fire Protection Systems at Electric Generating Plants

By Dominique Dieken, P.E., CFPS,
HSB Professional Loss Control
Introduction
Every year, fire suppression systems fail to operate satisfactorily in fire situations.
In about one-third of these cases, the cause is inadequate inspection, testing and
maintenance. An Edison Electrical Institute (EEI) study found that 49 percent of gaseous
suppression systems in combustion turbine units failed to operate satisfactorily in a
20-year period, with a total property damage of $15.9 million. An example of a fire with a
tragic consequence involved lube oil at a cogeneration plant on Christmas Day in 1992,
which resulted in the death of three plant operators. Automatic sprinkler protection was
provided for most of the plant, including lube oil hazards, but the systems had been
turned off! Had the system been operational, the fire may have been controlled.
Incidents like the one described above can be prevented with a good documented
inspection, testing and maintenance program, which will result in achieving maximum
reliability of the fire suppression equipment. This article is addressed specifically to
electric generating plants because of the wide range of fire protection systems found at
these plants. Below is a list of systems typically found at electric generating stations:
- Fire pumps
- Hydrants
- Sprinkler/water spray systems
- Hose houses
- Halon systems
- Dry chemical systems
- Halon-alternative systems
- Carbon dioxide systems
- Detection/alarm systems
- Portable fire extinguishers
Setting Up A Program
Fire hazards such as large quantities of fuel, combustible/flammable liquids,
electrical hazards, combustible dusts, and warehousing are common in electric power
generating plants. Although fires are not a daily occurrence, they usually will cause
severe property damage and business interruption. Many power generation plants are 10 to
20 years old, and sometimes the fire protection equipment systems have not received
attention since they were installed. If these systems are needed, however, they are
counted upon to perform reliably and protect vital plant equipment from fire. Fire
protection systems are a combination of mechanical and electrical components and, like
power generation equipment, need regular attention.
In addition, some people in charge of fire protection do not have an adequate knowledge
of necessary inspection and testing frequencies, or they use the minimum frequencies
prescribed by their authority having jurisdiction. For example, some jurisdictions only
require annual water flow alarm tests on sprinkler systems, a frequency which is
considered inadequate by most fire protection professionals.
The information contained in this article is based on the current standards established
by the National Fire Protection Association (NFPA), the most widely used in North America,
and generally accepted guidelines. Most fire protection systems are designed and installed
according to these standards. Unfortunately, information on inspection, testing and
maintenance is not contained in a single standard but is contained within the various
system-specific standards, making it cumbersome and difficult to obtain an overview of the
tasks which need to be accomplished.
Other codes and standards such as UBC, UFC, BOCA, OSHA and MSHA also address fire
protection, but their contents are usually based on NFPA documents and may not address
testing/maintenance requirements. Members on the NFPA technical committees comprise a wide
range of fire protection expertise and include representatives from manufacturers, testing
laboratories, users, authorities having jurisdiction and insurance companies. Adherence to
NFPA standards will satisfy most jurisdictions and insurance companies.
Getting Started
- The first step in establishing an inspection, testing and maintenance program is to
generate a list of all the fire protection systems at the plant. These typically range
from portable extinguishers to detection systems and automatic suppression systems.
- Once this list is complete, plant management needs to decide which tasks will be
completed by in-house personnel and which will be contracted out. This will depend on the
number and complexity of the systems as well as the availability and qualification of
in-house personnel. In some areas, state law dictates that any physical testing of fire
protection equipment must be performed by a contractor with an appropriate state-issued
license. A telephone call to the state fire marshals office should clarify this
issue.
- The next step is to determine the frequencies of the tasks. The guidelines in this
article will help to establish these. Other sources for determining frequencies include
the property insurance carrier or an independent fire protection consultant. Keep in mind
that different carriers have different requirements, although the gist is usually the
same.
- Then, a documentation system needs to be implemented. This can consist of paper forms, a
computerized preventive maintenance program (PM), or a modern bar code scanner system. Bar
code scanners with their associated software prompt the inspector to report to each
assigned station and to input the required data, thus making this type of system a
valuable tool for larger plants. Once the round is completed, data from the bar code
scanner is downloaded into a personal computer. The associated software then generates
reports and highlights any discrepancies, which should be reviewed by plant management.
Frequencies:
The frequencies below (see Tables at end of article) are intended as a quick reference
to help set up a program. See the appropriate standards or consult a fire protection
engineer for detailed information. Frequencies may need to be modified based on the
results obtained. This will maximize the effectiveness of the program while focusing the
time and budget on the problems which are most significant, based on actual test data.
Documentation:
Documentation is an essential part of a good program. The information contained on the
reports should accurately reflect the tasks performed. The reports should be clear,
concise, and well organized. For example, a work order stating "sprinkler
inspection" is not adequate because it does not provide information about alarms,
system pressures, riser condition, etc. Although there is no universal report
form, NFPA standards, fire protection manufacturers associations and property
insurance carriers publish forms which can be tailored to a particular application.
Whichever method of documentation is chosen, the records should be thoroughly reviewed
by management for discrepancies, acceptability of the results and any problems noted. The
records should be filed in chronological order in an accessible location for review and
use by other parties, such as for jurisdictional inspections and insurance company
surveys. The usually required record retention time is three to five years. These records
can also be used for trending analysis.
Impairments:
An impairment is an expression for a fire protection system which is out of service.
Impairments fall into two categories: planned and concealed. A planned impairment is
usually the result of maintenance or repair; a concealed impairment is usually
inadvertent. Frequent inspections help to prevent concealed impairments.
Whenever an impairment occurs, several procedures need to be followed. First, the
person responsible for safety/fire protection should be notified who should then inform
the plant manager. Then, appropriate third parties should be notified such as the fire
department, alarm company and the property insurance carrier. The severity of the
impairment must be analyzed by management. There may be alternative methods of fire
protection available while a primary system is impaired or the decision to take the
affected equipment out of service may need to be made. Before the system is taken out of
service, the affected area should be secured. This would include stopping hazardous
activities, shutting equipment down and posting a fire watch.
A conspicuous tag should be attached to the systems control valve to remind
personnel that protection is temporarily unavailable, and to turn the system back on after
the work has been completed. HSB Professional Loss Control provides its clients with
impairment pamphlets, impairment stickers for fire protection equipment and red impairment
tags.
Microbiologically Induced Corrosion (MIC):
A phenomenon found recently across the United States, but mainly in the Southwest and
West, this condition has caused premature corrosion in sprinkler system piping and heavy
tuberculation (scale which inhibits water flow). Some plants have reported that 5-year-old
sprinkler piping has developed leaks that warrant the replacement of piping or extensive
repairs. Underground piping does not seem to be affected because of increased circulation.
Tests have shown that a chlorine concentration of 3 ppm kills the microbes. This condition
is especially likely at plants which have their own water supply (wells, tanks and ponds).
If the water supply is from a municipal source, the water has most likely already been
chlorinated, but the level of chlorinating may not be enough.
Common Problems:
Downsizing often results in the reduction or elimination of jobs in the area of
maintenance, particularly for systems that do not directly generate revenue. As personnel
experienced with fire protection systems leave, fire protection-related tasks often are
assigned to inadequately trained personnel, or are not done at all.
- One frequent comment is: "We comply with the states requirements." Just
because a program complies with the requirements of a local jurisdiction or fire
department does not mean that the frequencies are adequate, but merely states that certain
minimum requirements are met. Compliance with NFPA standards is one of the best ways to
maintain an acceptable level of fire safety.
- Otherwise skilled technicians and mechanics are not necessarily qualified to perform
inspections, testing or maintenance on fire protection systems. These types of systems
have unique features and are usually subject to specific code requirements. Proper
training should be provided for personnel who work with fire protection systems.
- Just because a maintenance contract for a particular protection system is in place does
not mean that all necessary tasks are performed. For example, a halon system in a
combustion turbine enclosure requires testing of ventilation dampers, heat/flame/gas
detectors and unit trip interlocks, in addition to weighing cylinders and testing the
actuating valves.
- Regular fire department inspections are no substitute for a fire protection equipment
inspection and testing program. Contrary to popular belief, fire department personnel are
often unfamiliar with automatic fire suppression systems; their emphasis is on rescue,
manual suppression and potential hazards to firefighters.
- If private yard hydrants are used for wash-down purposes, the fire pumps should never be
turned off. Rather, a larger jockey pump, capable of supplying a small hose stream, should
be installed.
For Further Reading:
NFPA publishes several manuals and reference books covering specific systems, such as Fire
Protection Systems; Inspection, Test & Maintenance Manual; Fire Alarm Signaling
Systems and Automatic Sprinkler and Standpipe Systems. These publications can be
obtained directly from the NFPA, telephone (800) 344-3555.
Other relevant codes and standards include the following, each of which can be ordered
separately:
NFPA 10, Portable Fire Extinguishers
NFPA 12, Carbon Dioxide Extinguishing Systems
NFPA 12A, Halon 1301 Fire Extinguishing Systems
NFPA 17, Dry Chemical Extinguishing Systems
NFPA 25, Testing, Inspection and Maintenance of Water-Based Fire Protection Systems
NFPA 72, National Fire Code Alarm
NFPA 1962, Care, Use and Service Testing of Fire Hose Including Couplings and
Nozzles
Dominique Dieken, P.E., CFPS, is a senior engineer with HSB Professional Loss
Control, HSBs subsidiary fire protection engineering and consulting firm
headquartered in Tennessee. He provides field engineering for electric power generation
facilities in the western United States and Europe. Dominique is a graduate of Cal Poly
San Luis Obispo, is a registered fire protection engineer and holds a National Board
Commission. He is a member of NFPA and the Society of Fire Protection Engineers.
| Type of System |
Activities |
Recommended to be
performed by * |
Weekly |
| Fire Pump |
Fire pump churn test by automatic
operation, usually drop in sensing line pressure (10 minutes for electric, 30 minutes for
diesel) and associated engine inspections. Verify that pump running alarms are received in
control room. |
P.P. |
| Pump Suction Sources |
Check level of pond or suction tank. Also
check heating system during cold weather. |
P.P. |
| Valves |
Inspect indicating sectional and system
control valves to verify that they are in the open position (If they have neither locks
nor tamper switches. It is recommended that all valves be locked in the fully open
position). This should include special suppression systems. |
P.P. |
| Dry Pipe Sprinkler Systems |
Inspect dry pipe sprinkler riser
enclosures. |
P.P. |
| Low Pressure CO2 Systems |
Inspect liquid level of tanks. Tanks
should be refilled if a volume drop of more than 10 percent from the design requirements
is observed. |
P.P. |
Monthly |
| Fire Pump |
Test battery system, main circuit breaker
and isolation switch (electric pumps). |
P.P. |
| Fire Extinguishers |
Inspect each fire extinguisher and cart. |
P.P. or Contr. |
| Fire Hoses |
Inspect each fire hose station/hydrant
house. Hoses should be properly racked or rolled and the proper nozzles as well as hose
wrenches and other hardware should be provided. |
P.P. |
| Sprinkler Systems |
Inspect each sprinkler/water spray system
riser. This should include water/air pressures and alarm valves. |
P.P. |
| Special Suppression |
Inspect each system (agent level and
pressures, panels, nozzles). |
P.P. |
| Valves |
Inspect indicating sectional and system
control valves (locks and/or tamper switches provided). This should include special
suppression systems. |
P.P. |
Quarterly |
| Sprinkler Systems |
Test water flow alarms and perform main
drain test on sprinkler/water spray systems. |
P.P. or Contr. |
| Valves |
Test valve tamper switches by turning the
supervised valves until an alarm is obtained at the alarm panel. |
P.P. or Contr. |
| Post Indicator Valves (PIV) |
Test by turning them through the full
cycle and reopening them. Follow by a main drain test at the sprinkler riser controlled. |
P.P. or Contr. |
Semiannually |
| Special Suppression Systems |
Weigh high-pressure cylinders (halon, CO2,
halon-alternatives). Cylinders should be refilled if a volume drop of more than 10 percent
(CO2) and 5 percent (halon) from the design requirements is observed. Test
system actuators for proper operation. |
Contr. |
| Flame Detectors |
Test all flame detectors (UV/IR). |
P.P. or Contr. |
| Emergency Lighting |
30 second functional test. |
P.P. or Contr. |
Annually |
| Special Suppression Systems |
Test operation of CO2, halon
and halon-alternative systems, including auxiliary interlocks such as dampers or equipment
trips. |
Contr. |
| |
|
|
| Sprinkler Systems |
Trip test of dry pipe, preaction and
deluge sprinkler/water spray systems. A full discharge test should be conducted whenever
possible to verify free flow through all piping and nozzles. |
P.P. or Contr. |
| Antifreeze Sprinkler Systems |
Test specific gravity of solution in
antifreeze systems. |
P.P. or Contr. |
| Fire Pump |
Fire pump performance test (usually done
with insurance fire protection consultants). |
P.P. or Contr. |
| Hydrants |
Yard main flush/hydrant test (usually done
with insurance fire protection consultants). |
P.P. or Contr. |
| Fire Detectors |
Test all heat and smoke detectors. |
P.P. or Contr. |
| Fire Doors |
Test all automatic-closing fire doors. |
P.P. or Contr. |
| Gas Detectors |
Test/calibrate all combustible gas
detectors. |
P.P. or Contr. |
| Alarms |
Test alarm control equipment (batteries,
lamps, power supplies, etc.). |
P.P. or Contr. |
| Manual Fire Alarms |
Test all manual fire alarm boxes. |
P.P. or Contr. |
| Fire Extinguishers |
Service each extinguisher and cart. |
Contr. |
| Emergency Lighting |
90 minute functional test. |
P.P. or Contr. |
Other Than Annually |
| Fire Hoses |
Hydrostatic Test at 150 psi for most hose,
five years after installation, three years thereafter. |
Contr. |
| Portable Extinguishers |
Hydrostatic test, every 12 years for halon
and dry chemical (steel, brass or aluminum shells). Every five years for all other
extinguishers. |
Contr. |
| Carbon Dioxide |
Hydrostatic test of high pressure
cylinders every five years, 12 years if cylinders have been in continuous service without
discharge. |
Contr. |
| Halon |
Hydrostatic test of cylinders after
discharge, if more than five years have elapsed since the last hydrostatic test. |
Contr. |
| Standpipe Systems |
Hydrostatic and flow test every five
years. |
Contr. |