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Dry installations shall be designed in such a way, that the water- foam mixture reaches the test valve at
the end of the pipework within 30 seconds of system activation. This test can be performed using water
only.
P
P.2 Foam injection device
P.2.1The foam injection device shall be approved (GEI3).
Installer shall ensure that the foam injection device is compatible with the foam additive chosen.
Closed head sprinkler systems shall be designed so the proportioning of foam concentrate into the water
stream shall occur within 4 sprinklers flowing. Proportioning rate into the water stream shall be a
minimum of the foam concentrate approval e.g. 1%, 3%, 6%.
P.2.2 A foam solution test valve for foam concentration and an installation isolation valve shall be fitted
downstream of the foam injection device. The installation system isolation valve shall be located as close
as practical to the foam solution test valve. The foam solution test valve and installation isolation valve
shall be installed in accordance with the foam injection device manufacturers recommendations.
The commissioning of the installation shall include a test of the achieved foam concentration using
appropriate measuring devices. In a first test sequence water or test foam that has been designed to
simulate the flow and shearing characteristics of the foam concentrate can be injected in place of foam to
avoid unnecessary use of foam. At the initial system testing and commissioning, the foam concentrate
utilized for the system shall be utilized in the system commissioning.
For closed head sprinkler systems, tests shall be carried out with an equivalent flow rate of four sprinklers
and at the design flow rate of the system. The test at the design flow rate can be carried out by replacing
foam by another liquid. The injection device shall deliver foam solution within a tolerance not less than
its approval to 1.3 times its approval. A maximum of 1% point will be allowed. (Meaning 3% concentrate
shall be allowed to be proportioned between 3% and 3.9 %, 6% concentrate shall be allowed to be
proportioned between 6% and 7%).
Annual testing after the first year can be provided utilizing water or test foam using the comparative data
from the first year. If proportioning with the required range does not occur with water or test foam, a
new test with foam concentrate shall be made. Corrections to the proportioning system shall be made as
required injection device.
P.2.3 If the foam injection device utilizes moving parts, means shall be provided to allow a test of the
mechanical operating components. If the foam injection device utilizes electrical devices or electrical
controllers, means shall be provided to test the electrical devices or electrical controllers, means of
monitoring the working condition of electrical devices shall be provided. Foam injection devices shall
immediately be ready for service after testing and shall restore automatically.
P.3.1 Foam injection pumps shall be selected for the special working conditions like corrosion, tightness.
The performance characteristics of the foam injection pumps shall be selected for the maximum flow rate
and the viscosity of the foam agent. If foam injection proportioning devices are utilized in conjunction
with a foam injection pump, the minimum pressure differential between the water injection point and the
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