By Alyssa Dunn, General Manager, Dyne Fire Protection Labs
Abnormalities identified or found during the tasks outlined in NFPA 25, Inspection, Testing and Maintenance of Water-Based Fire Protection Systems can be classified as either a deficiency or an impairment. A deficiency is a condition that will or has the potential to negatively impact all or a portion of a fire protection system. A deficiency can be further classified as either noncritical or critical. An impairment is defined as a condition where a fire protection system or any portion of it is out of order, which can result in the system not functioning in a fire event. NFPA 25 Table A.3.3.8 helps aid in the classification of some abnormalities and indicates a sprinkler(s) that failed laboratory testing can be classified as either a critical deficiency or an impairment.
Critical Deficiency
A critical deficiency means the system may still operate, but not as intended. For example, a sprinkler that activates, but activates beyond the maximum allowed response time based on the RTI requirements could be considered a critical deficiency. In a fire event, the sprinkler may still operate, but not as quickly as intended. This is still critical, but the system is not completely impaired. Below are examples of sprinklers that activated during the sensitivity and functionality field testing, but failed to activate within the maximum allowed response time:
Impairment
An impairment is more severe – the system is compromised and all or a portion of it will not operate at all. Sprinklers that do not activate at all during the sensitivity and functionality testing could be considered an impairment. These are likely sprinklers that are impacted by heavy loading or corrosion which is preventing them from activating as they should. It could also be sprinklers which have water seals still intact or waterways completely blocked even after the release mechanism has activated. These failures would be considered an impairment since they are preventing the system, even if just a portion of it, from operating in the event of a fire. Below are examples of sprinklers that failed to activate during the sensitivity and functionality field testing:
How long do I have to address a Critical Deficiency or an Impairment?
Many jurisdictions have their own requirements for implementing corrective actions for critical deficiencies and impairments so check with your local jurisdiction first. In general, both critical and noncritical deficiencies should be corrected as soon as practical after considering the nature and severity of the risk. However, an impairment requires immediate action by either correcting the deficiency or implementing the impairment procedures found in NFPA 25 2023 Edition Chapter 15.
Questions? Contact us today by calling (800) 632-2304 or emailing dyne.lab@nfpaglobal.com.
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