Why Sprinklers Fail
IFR Africa tests sprinkler response times to ensure that the sprinkler operates within a specified time when exposed to a defined temperature and airflow. Acceptable response times are based on the Response Time Index (RTI). RTI requirements are listed below. Note that sprinklers coated with corrosion-resistant materials (such as wax) are allowed additional time per UL 199. Standard response coated sprinklers have a response time of 180 seconds or the maximum response time, whichever is greater.
Sprinkler Definitions:
- ESFR – RTI value less than 50 (meters-seconds) 1/2
- Fast Response – RTI value less than 65 (meters-seconds) 1/2
- Standard Response – RTI value less than 350 (meters-seconds) 1/2
If the response time does not meet the RTI requirement, the sprinkler response time will be marked as “FAIL”.
Failure to meet the RTI requirement may result from, but are not limited to, the following:
Loading
Corrosion
Paint
(other than that applied by manufacture)
Missing fluid in glass bulb
(if applicable)
Additionally, sprinklers that failed to release due to the release mechanism not activating, the water seal not releasing, or pressure loss not being detected due to a blocked waterway will be marked as “FAIL” on the report. If a sprinkler fails to meet the response requirements as defined above, all sprinklers within the area represented by the failure shall be replaced per NFPA 25 2023 Ed. Section 5.3.1.3.
IFR Africa will also provide an image of the waterway following the response time test. The image of the sprinkler waterway post-testing can be used to help identify any obstructions that may still impede functionality.