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• Support for Research
  Joseph M. Fleming
  Published on: 13 May 2016

• Published on: 13 May 2016

  Support for Research

  • Joseph M. Fleming, Deputy Fire Chief

  Dear Editor

  First I want to thank the authors for an excellent study. As the authors discuss, the benefit of using photoelectric technology to reduce smoke alarm disablement and thereby fire deaths has never been adequately communicated to the public. (Note: This author has made repeated requests, accompanied by extensive research, to the National Fire Protection Association (NFPA), Underwriters Laboratories...

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  Dear Editor

  First I want to thank the authors for an excellent study. As the authors discuss, the benefit of using photoelectric technology to reduce smoke alarm disablement and thereby fire deaths has never been adequately communicated to the public. (Note: This author has made repeated requests, accompanied by extensive research, to the National Fire Protection Association (NFPA), Underwriters Laboratories (UL) and the Consumer Product Safety Commission (CPSC) to inform the public but no action has been taken.)

  The authors may be interested to know that the following language has been contained in the Massachusetts State Building Code since 1998. "Section 919.3 - Where required: single and multiple station smoke detectors or household fire warning systems shall be installed and maintained in full operating condition in the locations described in 780 CMR 919.3.1 through 919.3.3. Any smoke detector located within 20 feet of a kitchen or within 20 feet of a bathroom containing a tub or shower shall be a photoelectric type smoke detector."

  This decision was based on research submitted by this author that is not available in the public health literature.

  From a study published in NFPA’s Fire Journal, “ ... We favor photoelectric detectors to reduce rates of nuisance alarms from cooking and to provide optimal protection from cigarette related fires. Electrical detectors with battery back-up are the detectors of choice, except in communities such as remote villages in Alaska, where alternating current is non-existent or unreliable. If ionization detectors are installed, they should be located at least 20 feet, and preferably 25 feet, from stoves and at least 10 feet from bathroom doors if possible." (KuKlinski, Diana, Berger, Lawrence, and Weaver, John, "Smoke Detector Nuisance Alarms - A Field Study in a Native American Community", Fire Journal (Sept/Oct 1996) pp. 65-72.)

  In a study in Woodlands, Texas, 90% (115/126) of the total number of false alarms were recorded by the ionization detectors, 86% (83/95) of the non-malfunction alarms were caused by cooking. This study clearly shows that the most common source of false alarms in a residential setting is cooking and that ionization detectors are clearly more susceptible to these types of false alarms. (Moore, D.A., "Remote Detection and Alarm for Residences: The Woodlands System", U.S. Fire Administration, Emmitsburg, Md., May 1980.)

  In a manual published by one manufacturer titled "A Method For Improving Smoke Detector Codes In The United States, the manufacturer recommends using photoelectric detectors in, "Existing small apartments where kitchens or open flame heaters are adjacent to sleeping area." This manufacturer also recommends using a photoelectric detector if you have to place a detector within 20 ft of a furnace or heater. ("A Method for Improving Smoke Detector Codes In the United States", prepared by BRK Electronics, (1987).)

  The authors have contributed valuable research to the previous work. I have already forwarded it to the various boards and committees that I am dealing with which type of smoke alarm to require.

  If I may add some additional comments on the following topics discussed by the authors.

  1. The authors cite 2 studies showing that, "smoke alarms are effective interventions for injuries from residential fires."

  Comment

  I agree that smoke alarms are better than nothing but this information has to be put in context. The authors conclude that having a smoke alarm is better than not having a smoke alarm. This is almost self evident. But neither investigated whether or not one type was better than another or if there were scenarios were it should have made a difference but didn’t. Neither author was probably aware, because it was never publicized, that in the late 80's UL and the smoke alarm manufacturers decided to de-sensitize smoke alarms, i.e. ionization smoke alarms, to help reduce the nuisance alarm problem. Since this de-sensitization has taken place the % of fire fatalities with working alarms has doubled. (US Fire Administration Data)

  A 2004 Report issued by the NFPA, after this de-sensitization, found that smoke alarms reduced the risk of dying in a fire by only 7% for apartment dwellers. This report also estimated that the reduction risk for all residential occupancies was only 21%. (Ahrens, M., “U. S. Experience with Smoke Alarms and Other Fire Detection Alarm Equipment,” National Fire Protection Association, Quincy, MA November 2004.) In any case, researchers cannot identify how much of the reduction in risk is not due to the effectiveness of the detector but rather due to occupant characteristic that go along with owning a smoke detector: higher income, newer construction, better evacuation plans etc? All of these factors would contribute to a reduction in fire risk. As a consequence, the actual reduction in risk due to the effectiveness of the detector is probably much less that 21%. Smoke alarms do reduce risk but do they reduce it as much as we think they do?

  Since, according to the CPSC, approximately 90% of the smoke alarms in use are ionization, then these statistics refer to the effectiveness of ionization alarms. This relatively small amount of risk reduction is due to the failure of the ionization alarm to adequately sense smoke created by smoldering fires, such as those started by smoking. "NIST officials told the Boston City Council's Public Safety Committee in August that "ionization alarms may not always alarm, even when a room is filled with smoke from a smoldering fire." Scientists have reached similar conclusions in Norway, Australia and England." ("Smoke Detector Alarming Limits," Roylance, F., Baltimore Sun, March 4, 2008.)

  2. The authors discuss the cost of different technologies and list the following prices: ionization - $10, photoelectric $15, and dual sensors for $25.

  Comment

  The Boston Fire Department has provided photoelectric smoke alarms in our free give-away program for approximately ten years. The last pricing information that we received was $5.75 for ionization and $8.00 for photoelectric. It appears that much of the price differential at the retail level is due to marketing as opposed to manufacturing cost differences. It is not unreasonable to assume that if photoelectric alarms captured 90% of the market that benefits of "economies of scale" would change the price differential. In addition, in new construction the total price included wiring and labor so the total price differential is negligible.

  Let me conclude with the following information:

  Due to this author’s research the Massachusetts Board of Fire Prevention Regulations approved the following language. (It will become effective on October 1, 2008.)

  32.02: Definitions

  Approved monitored battery power smoke detector, shall consist of a working device, as defined in M.GL.c148, s. 26D. However such device shall not include a device that employs ionization technology as the sole means of smoke detection.

  Approved primary power smoke detector, shall consist of a working device, as defined in M.GL.c148, s. 26D. However such device shall not include a device that employs ionization technology as the sole means of smoke detection.

  32.03 Installation of Smoke Detectors In the Vicinity of a Kitchen, Bathroom or Other Areas.

  No smoke detector employing ionization technology shall be installed within 20 feet of an entryway to a kitchen, or bathroom containing a bathtub or shower or any other room or area which features any item which produces steam or moisture. The 20 foot measurement shall include and extend into common areas of a multi-family dwelling, if applicable.

  Due to this author’s research the Governor of Vermont will sign the following legislation. (It will become effective on January 1, 2009.)

  (a) A person who constructs a single-family dwelling shall install one or more photoelectric-only-type smoke detectors in the vicinity of any bedrooms and on each level of the dwelling, …

  (b) Any single-family dwelling when transferred by sale or exchange shall contain one or more photoelectric-only-type smoke detectors in the vicinity of any bedrooms and on each level of the dwelling installed in accordance with the manufacturer's instructions …

  This research paper is additional evidence supporting my efforts to educate the public regarding the differences in smoke alarm technology and I appreciate the authors’ thoroughness. Hundreds of lives can be saved each year if the public is provided with this type of information.

  Jay Fleming Deputy Chief Boston Fire Dept.

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  Conflict of Interest:
  None declared.

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