How many heads must be on a system before supervision is required?

In sprinkler system design and installation, the requirement for supervision typically hinges on the number of sprinkler heads present in a system. Supervision refers to the monitoring of sprinkler systems to ensure they operate correctly, especially in the event of a fire.

For systems with a greater number of heads, the potential impact of any single head's failure increases, so supervision becomes crucial. If a system has 20 or more sprinkler heads, supervision is mandated because this threshold implies that the system is large enough that the failure of an individual head or other components could significantly affect performance and safety.

Also, supervisory control can include monitoring for flow, pressure variances, and other mechanical failures, ensuring that the firefighting capacity remains reliable under emergency conditions. This requirement is aligned with national codes and standards to enhance safety in larger installations while ensuring that the appropriate level of oversight is maintained for effective firefighting response.

Hence, the requirement for supervision kicks in at 20 heads, making it essential for systems of this size and above to have proper oversight mechanisms in place.