FAQ

NFPA 25 does not require any system modifications to bring an old system up to present
standards. There are exceptions however. If the authority having jurisdiction determines that
an unsafe condition exists, Section 1.2 permits corrective action in excess of the minimum
requirements of the standard. Another exception to this requirement can be found in
Section5.3.1.11.1 which states “sprinklers installed prior to 1920 shall be replaced”

NFPA is not intended to address installation deficiencies. In fact, Section 1.1 states
“Where a system has not been installed in accordance with generally accepted practices, the
corrective action is beyond the scope of the standard”

Many state or local jurisdictions require licensing or certification, NFPA 25 does not. Section
4.1.2.3 states that “These tasks shall be performed by personnel who have developed
competence through training and experience”.

Section 4.5.6 requires testing in accordance with the original acceptance test for that
component or subsystem. This information can be found in the installation standard for the
type of system involved.

There are two activities that are related to obstructions in Chapter 13 that require our
attention. The first is an investigation that is actually more of an “inspection” as described
in Section 13.2.1 that must be conducted every five years. While the sprinkler system is shut
down for the purpose of internal valve inspections (See Table 12.1), the flushing connection
at the end of one crossmain and a single sprinkler at the end of one branchline must be
NFPA 25 – FAQs
removed and the inside of the piping is then “inspected” for the presence of organic and
inorganic material.
In Section 13.2.2 a more comprehensive obstruction “investigation” must be conducted
when any of the 14 conditions listed in that section are present. This more comprehensive
obstruction “investigation” is conducted by internally examining the following four points in a
system: system valve, riser, cross-main and, branch-line and is only required when one of the
14 problems listed in Section 13.2.2 is present. This obstruction investigation is not a routine
procedure, it is only needed when a problem exists. If any obstructing material is found, a
complete flushing program must be conducted to remove any remaining obstructing
material.

Bags are only permitted when sprinklers are protecting spray coating areas. Plastic bags must
have a minimum thickness of 0.003 in. (0.076 mm) or small paper bags may be used.
Sprinklers protecting areas other than spray coating hazards are not permitted to have bags
placed over the sprinklers.

Individual sprinkler sample refers to each type of sprinkler in a system. For example, if a
system contains upright and pendent sprinklers, one percent or not less than four of each
type must be removed for testing.

In your case, a sample from each tenant space is not required. The sampling requirement in
Section 5.3.1.2 is intended to be random sampling, meaning that sprinklers should not be
removed from a single branch-line but should be taken from a number of different areas in a
building (where practical). Removing sprinklers from as many different areas as possible will
better represent the condition of all or most of the sprinklers in that system.

Section 5.3.1.2 requires that one percent (or no less than four) be removed and submitted to
a testing laboratory for evaluation. If a system contains 500 sprinklers for example (400
upright and 100 pendent) then a total of eight sprinklers must be removed; 400X.01=4 and
100X.01=1 (but not less than 4).

A small amount of water in the baseplate drain is normal. This water should be dripping from
the packing glands. The packing glands on the pump must be kept wet for proper lubrication
(about one drop per second). Never adjust the packing gland to stop the dripping of water.
To do so will prevent lubrication and will result in the destruction of the packing gland.

This may not be a problem. First, you should verify that all valves on the suction side of the
pump and in the test header are open fully. Some decrease in performance can be expected
due to slight wear of the pump or its components, this is normal. The annual test is intended
to ensure that the pump is capable of supplying the maximum system demand. The test
results from the annual test are not required to meet the original pump curve as in the
original acceptance test.

You have several options, they are:
 use the fire pump test header, if present, as a test connection
 if the backflow preventer is installed on the suction side of the pump, the annual fire
pump test will also serve as a flow test for the backflow preventer
 the fire department connection may be used as a test connection by reversing the check
valve and flowing water out of the FDC. It might be a good idea to install a by‐pass
around the check valve with a normally closed control valve for future testing

A main drain test is required annually or any time the water supply control valve is closed,
this includes any time a system undergoes maintenance or repair. This test is essential to
NFPA 25 – FAQs
ensure that the water supply valve is fully open. Sprinkler systems perform exceptionally
well, however when they do fail the major cause of failure (35% of the cases reported to
NFPA) the water supply valve was closed, thus the verification of an open water supply valve
cannot be over emphasized. The annual test frequency is a minimum requirement, NFPA 25
permits more frequent testing if desired.

MIC or microbiologically influenced corrosion is the result of certain types of bacteria in the
water that attack steel and copper pipe. MIC can be recognized by the presence of orange or
black tubercules or black mud‐like slime in steel pipe and blue or green tubercules in copper
pipe.
The best approach to address this situation is to submit a sample of the corrosion by‐product
to a laboratory for testing (such labs can be found on the internet) and identification of the
microorganism responsible. Once identified, a treatment strategy can be developed. This
may involve altering one or more environmental conditions inside the pipe such as: oxygen
levels, pH, temperature or residual chlorine content. If the problem is MIC, treatment of the
water will be necessary each time you test or flush your system. Introducing a fresh supply of
water and oxygen may allow the MIC to renew its attack on the pipe.