Learn how to calculate fire alarm battery backup capacity per NFPA 72 Section 10.6.7. Includes standby load, alarm load, and battery selection worked examples.
NFPA 72 Section 10.6.7 requires every fire alarm system to have a secondary power supply — typically a sealed lead-acid (SLA) battery — capable of operating the system for 24 hours in standby followed by 5 minutes at full alarm load. For systems with emergency voice evacuation, the requirement jumps to 24 hours standby plus 15 minutes alarm. Undersized batteries are one of the most common code violations found during inspections.
Topics covered
NICET Fire Alarm Level I — Extended Practice Exam
✨ Premium ContentGo beyond the free practice questions with a full-length paid exam bank.
Fire Alarm Design Professional Training Program
✨ Premium ContentA structured, paid professional training program for this discipline.
NICET Fire Alarm Level II Study Guide (Full Access)
✨ Premium ContentA zoomable interactive reader — free preview, then unlock the full set.
Cross-Zoned vs. Single-Zone Detection — A Deliberate Tradeoff, Not a Universal Upgrade
✨ Premium ContentA paid interactive calculator or 3D simulator for this discipline — part of the All-Access Pass.
📬 Get new engineering guides in your inbox
New calculators, interactive readers, and reference guides — no spam, unsubscribe anytime.
Put this knowledge to work on your iPhone
Browse our full catalog of professional iOS apps — from electrical code tools to AI builders.
Browse All 95+ Apps