3 FM quick reads on NFPA 72
1. Fire Code Clarifications NFPA 72
As fire codes are revised, changes to the code are clarified and refined. This, argues Wayne Moore in a brief from the latest issue of NFPA Journal, is why facility managers and any one else that interfaces with a fire life safety system should be aware of the latest version of the code, even if their jurisdiction enforces an older version for the code.
For example, on area of confusion that is addressed in the latest version of NFPA 72, National Fire Alarm and Signaling Code, is intelligibility related to in-building fire emergency voice communication systems or mass notification systems. This is a relatively new aspect of the code, which can lead to some confusion around what the code actually requires. The code requires intelligibility, but it never intended to require that this intelligibility had to be quantitatively measured, says Moore. Doing so might be a great idea, but the technical committee only intended to require that people in the space understand the voice message. Exactly proving this through quantitative measurements is gravy. Moore says the problem is that misunderstanding the actual requirement could delay acceptance of a project by AHJs, hold back the occupancy permit, and add cost.
Another area of confusion around intelligibility is the "acoustically distinguishable space." Different spaces will behave differently from an acoustics standpoint because of physical characteristics of the space or how the space is used. So when designing systems for voice intelligibility, these space variances have to be taken into account. This concept came into the code with the 2010 edition of NFPA 72. However, in the 2013 edition the code was refined to clarify that not all acoustically distinguishable spaces necessarily have to support voice intelligibility (absent any other applicable codes, laws, or standards that might require intelligibility.) In Annex A, a list of spaces that might be exempt for the intelligibility requirements includes mechanical rooms, private bathrooms, kitchens and other similar spaces where it would be impractical to achieve intelligibility. In these spaces, alternatives to voice evacuation might be required, Moore says.
Read the original brief here.
Code Guidelines on Mass Notification Available, Not Required
Fire safety considerations are often interwoven with mass communication or emergency communication considerations. However, at this time, emergency communication systems are not a requirement of NFPA 72: National Fire Alarm and Signaling Code. Rather, it provides the design, installation, and maintenance requirements and guidelines for systems if they are required by local codes or other governing authorities or if an owner decides to voluntarily implement an emergency communication system within a building or area, says Ray Grill, a principal with Arup, in an article in the September 2013 issue of Building Operating Management.
"There are currently no known requirements in the building or fire codes mandating mass notification," he says. That said, building and fire codes establish when a fire alarm system is required in a facility and what it needs to be able to do. Sometimes, that includes a communications component, such as in high-rise buildings, large assembly and schools. While the systems in those situations would not be mass notification systems per se, they could be designed to function as such.
There are many communications tools available for communicating emergency information to a large number of people that still wouldn't be defined as emergency communications systems in NFPA 72. For example, automated text message generated by a computer alert or phone communications are not considered part of an emergency communication system, though they can certainly serve to augment one.
In addition to listing under NFPA, mass notification equipment is listed under the Underwriters Laboratories standard UL 2572: Control Equipment for Mass Notification Systems. The standard covers control units, communication units, distributed recipient mass notification control units and dedicated targeted individual receiving equipment, high power speaker arrays, transport products which manipulate the data packets, and accessories for mass notification systems to be employed in accordance with NFPA 72.
Fire Alarm Systems Requirements For Use In Emergency Communications
Fire safety covers many different building systems and concepts. One of them is the need for effective emergency communications in the event of a fire, and other emergency situations. Fairly recently, codes have recognized that fire alarm systems can be used for emergency communications beyond fire events. This use is governed by NFPA 72: National Fire Alarm and Signaling Code, and the 2010 edition of this code is the first to allow the use of fire alarm systems for emergency mass communications in non-fire events.
To note, existing fire alarm systems with voice capability can be used for emergency communication, but existing mass notification systems can not be also used for fire, unless they were originally designed for that purpose, says Ray Grill in an article in the September 2013 issue of Building Operating Management. Also if a system will provide both fire alarm and emergency communication, the fire alarm requirements are more restrictive, he says.
Once you move out of just using the fire alarm system for fire events, there is a wide range of events that it could be used to address. For this reason, NFPA 72 requires a risk analysis be performed to investigate the types of events the system will be asked to address, the nature of the hazards, occupancy characteristics and facility characteristics. This will ensure that the application of the mass notification system is specific and appropriate to the anticipated risk.
The risk analysis will also need to cover the number of people that will need to be notified in each type of event, occupant attributes such as whether they are resident population or public that just moves through the facility, management and staff capabilities and who are the first responders for each type of event.