More stringent maintenance requirements for foam systems

Monday 06 May 2013

We would like to inform you about the stricter requirements concerning maintenance executed conform NFPA 25. Based on this regulation maintenance inspection is being done by an official inspection institution. The following extra work is required due to the new more stringent regulations. It concerns work that is not part of the standard yearly maintenance.


  • Solenoids and cylinders have to be activated or operated with the sprinkler alarm centre every month


  • Check control valves (used with bladdertanks)
  • Check control valves (used with self suction proportioners)
  • Check cylinders/actuators of the actuated valves
  • Clean solenoids
  • Check proportioning rate of proportioners
  • Check foam pumps on capacity and pressure (use data from commissioning as reference)
  • Execute foam proportioning and/or water reference test
  • A quality foam concentrate test (EN-1568) has to be performed

Every 3 years

  • Control valves (used with bladdertanks) must be equipped with new seals/rubbers
  • Open cylinders/actuators and provide with new seals/rubbers
  • Replace all rubber seals of the control valves, this also applies to the pressure regulators
  • Hi-Ex installations – check pipes and nozzles for debris

Every 5 years

  • Foam proportioners have to be maintained conform instruction of the manufacturer
  • The balancing head of the balanced pressure proportioner has to be cleaned thoroughly. For this activity it needs to be dismantled

Every 10 years

  • Draining and rinsing of the foam concentrate tank
  • Check foam concentrate tank and suction/discharge line in the tank for rust and debris
  • Perform hydraustatic test on foam concentrate tank

What to do after extinguishing

When an installation has been activated it is important to follow through these steps:

  • A dry system will show a mixture of water and foam concentrate in the lines. If these are not rinsed thoroughly it could have dramatic consequences that can go so far that the installation will not function properly anymore. The pictures show what can happen if the lines are not rinsed thoroughly. Furthermore the content of the bladdertank or pressureless tank will not be sufficient according to system requirements.
  • Rinsing water must be checked for foam concentrate
  • Foam concentrate storage must be refilled to the required content.

In case of emergency InnoVfoam service is available 24 hours a day in order to lend you professional support for measuring the present content of the foam concentrate storage.