Oxygen Reduction Systems
Oxygen reduction systems permanently lower the oxygen concentration in a protected space below the ignition threshold of the fire load present, preventing a fire from starting rather than fighting it once ignited.
Operating Principle
On-site generated nitrogen typically lowers the oxygen concentration in the protected area to between 13 and 17 percent by volume, depending on the ignition threshold of the specific fire load. Oxygen sensors continuously monitor the concentration and adjust the nitrogen supply accordingly, keeping the target level stable throughout ongoing operation.
Applications and Constraints
Typical applications include high-bay warehouses with sensitive goods, archives, cold stores and data centres. The protected space must be sufficiently airtight so the reduced oxygen level does not dissipate through air exchange. Personnel who regularly enter the space are subject to occupational exposure limits, access controls and separate oxygen monitoring.
Insurance Relevance
Because a fire cannot start under normal operating conditions, oxygen reduction is regarded as a highly effective preventive measure for storage areas that are hard to access or sensitive to water damage. Insurability depends on unbroken documentation of the continuous oxygen concentration through operating logs, since an undetected excursion above or below the target level immediately negates the protection.
Standards and codes
- FM Data Sheet 4-13 – Oxygen Reduction Systems