Photosensitive epilepsy

Sweeping technical changes are proposed for one of NFPA's most frequently used documents.

DURING THE LAST 18 months, the technical committees responsible for NFPA 72(R), National Fire Alarm Code(R), have been developing changes for the 2002 edition, which is up for adoption by NFPA members at the World Safety Conference and Exposition(TM) in Minneapolis in May. With the membership vote to adopt the new edition of the code, it will be published in September.

This new edition represents countless hours of work by committee volunteers, NFPA staff, and users of the code. At the Report on Proposals meetings, held in San Antonio, Texas, in January 2001, committee members processed 587 proposals, a large number of which were submitted by those who use the code. And at the Report on Comments meetings also held in San Antonio during December 2001, committee members processed 422 comments on the proposals.

Among the most visible changes is another restructuring of chapters to conform to the 2000 edition of the Manual of Style for NFPA Technical Committee Documents, the use of which was mandated by the NFPA Standards Council. Because the style manual requires a separate chapter for administrative rules, referenced publications, and definitions, the current chapter on fundamentals was broken up to provide material for the new administrative chapters.

Overall, the code has been reorganized as follows: Chapter 1, Administration; Chapter 2, Referenced Publications; Chapter 3, Definitions; Chapter 4, Fundamentals of Fire Alarm Systems; Chapter 5, Initiating Devices; Chapter 6, Protected Premises Fire Alarm Systems; Chapter 7, Notification Appliances for Fire Alarm Systems; Chapter 8, Supervising Station Fire Alarm Systems; Chapter 9, Public Fire Alarm Reporting Systems; Chapter 10, Inspection, Testing, and Maintenance; and Chapter 11, Singleand Multiple-Station Alarms and Household Fire Alarm Systems.

In addition, the code's appendices were renamed "Annexes." Annex A will include explanatory material. Other annexes will include an Engineering Guide for Automatic Fire Detector Spacing, a sample ordinance; extracted sources; and nonmandatory referenced publications. All measurements will now appear in metric units, followed by the English units in parentheses.

For ease of reference, the section and chapter numbers that follow are those used in the 1999 edition of NFPA 72.

Existing Chapter 1

In the definitions section of the existing Chapter 1, Proposal 72-46a and Comment 72-30 changed the term "non-required system" to "non-required (voluntary) system" to indicate that non-required systems are voluntarily installed and aren't required by building or fire codes. Section 3-2.4, which makes it clear that even voluntarily installed systems must meet the requirements of NFPA 72, was also revised to reflect this change in terminology.

Section 1-6.1.1 was revised to add shop drawings to the list of documents that must be submitted upon request to the authority having jurisdiction (AHJ), and new annex material was added to explain what shop drawings are and what they should contain. This change should result in better documentation and quality control before installation.

Also intended to result in better quality control was a change to the requirements of Section 1-6.2.3, which in the 1999 edition contains specific requirements for certifying and placarding central station fire alarm systems. The revision extends these requirements, in a more general way, to all fire alarm systems, including protected premises (local) systems and supervising station systems. This revision provides a framework for implementing third-party verification when required. Specific requirements for certifying and placarding central station systems can still be found in the chapter on supervising station fire alarm systems.

Yet another change in documentation requirements will require that the installer provide the owner with a record copy of the site-specific software for the system. This change, made by Proposal 72-140, was intended to provide a means of quickly returning the system to normal following a catastrophic equipment failure, such as that caused by a lightning strike.

Proposal 72-69 completely re-organizes the power supply requirements of Section 1-5.2 and provides performance characteristics more consistently. Exception Number 2 and Exception Number 3 to Section 1-5.2.3, which allowed installers to eliminate the secondary power supply where primary power was supplied by a dedicated branch circuit of an NFPA 70, National Electrical Code(R) (NEC(R)) Article 700, 701 or 702 system, have been eliminated. NEC Articles 700, 701 and 702 define the requirements for emergency, legally required standby and optional standby power systems, respectively. A primary and secondary power source will now always be required.

Other major changes to power supply requirements include a revision of the secondary power supply capacity requirements of Section 1-5.2.6. Emergency voice/alarm communications systems will require 24 hours at quiescent load and, at the end of that period, 15 minutes of all call. All other systems will require 24 hours at quiescent load and 5 minutes of alarm. The requirements for 60 hours of secondary power for auxiliary and remote station systems will no longer apply.

The rules formerly in Section 1-5.4.3.2.2 will now provide indication and response requirements specific to both latching and non-latching supervisory circuits. In addition, rules formerly in Section 3-8.3.3.1.3 will permit the use of supervisory signals that latch in the off-normal state, where approved by the AHJ. These changes clearly allow supervisory signals to be latched where it's appropriate for someone to respond, such as for the situation of an unauthorized valve closure.

Existing Chapter 2

Section 2-3.6.6.1 requires a reduction in the spacing of smoke detectors in areas of high-- air-movement, based on the number of air changes. However, spacing needn't be reduced in heating, ventilating, and air conditioning mechanical rooms used as plenums for return air, according to a proposed new rule. This is based on the rationale that reduced spacing under these conditions doesn't improve response time.

Proposal 72-185 added a requirement for signage on the manual fire alarm boxes of protected premises (local) fire alarm systems. These signs, intended to let occupants know that the system doesn't summon firefighters, must instruct occupants to leave the building and call the fire department. They must also provide the emergency telephone number.

A new section was added near the beginning of the initiating devices chapter to establish requirements for documenting and approving performance-based designs for detection systems. Companion changes made by Comments 72-144 and 72-147 to the general requirements for heat and smoke detectors address performance-based design.

Existing Chapter 3

Proposals 72-261 and 72-262 moved the requirements for both presignal features and positive alarm sequences from the chapter on fire alarm system fundamentals to the chapter on protected premises systems. Also moved from the fundamentals chapter to the protected premises chapter were the existing requirements for fire safety function and alarm signal actuation times, which were also consolidated. Both changes were made because the requirements apply only to protected premises systems, not all fire alarm systems.

Comment 72-192 removed existing Section 3-8.3.1.2, which requires a manual fire alarm box on any system that uses automatic fire detection or water-flow devices. The section was cut because the requirement is also found in occupancy level codes and needn't be repeated in NFPA 72.

Existing Chapter 4

One of the most interesting of the proposed changes relates to voice intelligibility Proposals 72-318 and 72-319 revised former Section 4-3.1.5 to require that messages produced by emergency voice/alarm communications systems have an intelligibility score of 0.70 on the Common Intelligibility Scale. This proposal was modified by Comment 72-270, which added the words "where required" to the beginning of the paragraph.

Annex material was added to explain that there may be spaces in some applications that don't require intelligible voice signaling. Requirements for measuring voice intelligibility testing weren't added to the testing and maintenance chapter, but Proposal 72-443 added annex material identifying methods of verifying intelligibility.

New sections were added allowing the reduction or elimination of audible fire alarm signals where public mode visible signaling is provided in accordance with the code, as long as the AHJ approves the move or it's allowed by other governing codes or standards.

Another change affecting the requirements of Section 4-3.4, raises the criteria for minimum sound pressure levels in sleeping rooms from 70 dBA to 75 dBA. Not only does this correlate with international codes, but industry data suggest that an audible signal of 75 dBA is needed to awaken the average sleeper.

Requirements for visible signaling have also changed. Section 4-4.4.1.1(3), which permitted non-synchronized strobes if they were at least 55 feet (16.8 meters) apart in a room that measured at least 80 feet (24 meters) by 80 feet (24 meters), was deleted, and a new requirement synchronizing visible signals in corridors was added.

Both changes are intended to make synchronization requirements for visible notification appliances uniform and prevent seizures in persons with photosensitive epilepsy.

Existing Chapter 5

One of the biggest changes proposed for the chapter on supervising station fire alarm systems will require third-party verification for remote supervising stations. The proposed change calls for either certification or placarding, similar to the requirement for central stations, or compliance with state or local government programs that act as a means of third-party verification. Some local jurisdictions have programs already in place to serve as a surrogate to certification and placarding.

The same proposal also requires remote supervising stations to transmit supervisory signals, as well as alarm signals, because many remote stations supervise sprinkler systems. Transmitting an indication of off-normal conditions allows corrective action to be taken.

Existing Chapters 7 and 8

Proposal 72-431 revised the requirements of Section 7-1.6.2.1 to reduce the scope of reacceptance testing following system modification. The revised requirements now specify that tests focus directly on affected components, rather than examining much of the system for small changes.

The technical correlating committee directed that all testing and maintenance requirements be consolidated in a single chapter, moving the testing and maintenance requirements related to single- and multiple-- station alarms and household fire alarm systems to the chapter on inspection, testing, and maintenance.

In addition, the functional testing frequency for single- and multiple-station smoke alarms was extended to once annually. However, NFPA 72 also requires smoke alarms to be functionally tested in accordance with the manufacturer's instructions, and these instructions often specify monthly, sometimes even weekly, tests.

Technical committee members, NFPA staff, and interested parties have invested a great deal of time and effort in improving NFPA 72, one of NFPA's most frequently used documents.

While it may take some time to get used to the organizational changes, they'll make the code easier to use in the long run and more compatible with other NFPA documents.

Many of the technical changes will also make the code requirements easier to understand and enforce. The changes are subject to change since NFPA and the Standards Council haven't approved them yet.

MERTON BUNKER, P.E.

MERTON BUNKER

is a senior consulting

engineer with Rolf Jensen

and Associates at its

Fairfax, Virginia office.

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