From the September/October 2011 issue of NFPA Journal®
By Wayne Moore, P.E., FSFPE
Major events such as the terrorist attacks on Khobar Towers in 1996, the terrorist attacks on the World Trade Center and the Pentagon on September 11, 2001, and the shootings at Virginia Tech in 2007 have all had an impact on the NFPA code-making system, resulting in new requirements that appear in the 2010 edition of NFPA 72®, National Fire Alarm and Signaling Code®.
One example is that, for the first time, NFPA 72 now allows another emergency signal to take precedence over a fire alarm signal. Chapter 23, Protected Premises Fire Alarm Systems, of Section 220.127.116.11 states that "Fire alarm signals shall have priority over all other signals." A clarification to this rule in Chapter 10, Fundamentals, states that "Fire alarm signals shall take precedence over all other signals, except as permitted by 10.6.1 or 10.6.3." Section 10.6.1, pertaining to emergency communications systems, notes that "ECS priority signals when evaluated by stakeholders through a risk analysis in accordance with 18.104.22.168 shall be permitted to take precedence over all other signals." More specifically, Section 10.6.3 states that "Emergency mass notification signals and messages shall be permitted to have priority over fire alarm notification signals in accordance with the requirements of Chapter 24."