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Dimmable Warning Lights Extinguished?

By Bill Adams

From the July 2019 Fire Engineering: “The National Fire Protection Association (NFPA) Standards Council has announced that the information in the NFPA 114 Emergency Response and Responder Safety (ERRS) standards, guides, and recommended practices will be consolidated into ‘38 overarching standards.’ The five-year process, which will begin in January 2020, will involve combining 20 to 25 standards annually in their proper cycle. Related standards will be merged into all-inclusive standards; existing documents will become separate chapters.”

Several matters of interest come to mind—some minor and some that could be significant. Currently, there’s a half-dozen or so standards applicable to fire apparatus. In particular, NFPA 1901, Standard for Automotive Fire Apparatus, is a 200-plus page document that costs $80.00 to purchase. It is a long document that could be difficult to confusing for the average back-step firefighter to decipher and understand. A new member of an apparatus purchasing committee might not care about items such as refurbishing apparatus, ambulances, or aerial ladder testing but, in the future, may be obligated to purchase one large document just to access NFPA 1901 data. According to the aforementioned Fire Engineering article, NFPA 1901 content will become a separate chapter in a larger document. While the particulars are not yet known, the amalgamation of all apparatus standards into one possibly very large document may not be in the best interests of an apparatus purchasing committee. Time will tell.

“In addition, ERRS standards will have a new revision cycle: Both the first and second draft meetings and any necessary correlating committee meetings will occur during the same year. One meeting will be held in January and the other in November.” I understand making life easy for the NFPA committee members. However, it appears—and I say it appears only—that mandating that a committee’s work must be completed in one year may not allow enough time for the public to make comments and a committee to respond to them. Again, time will tell.

One example of a “time constraint” is the current “concern” with dimmable warning lights—aka having a separate performance requirement for fire apparatus warning lights while in the blocking the right-of-way mode. It appeared to me that there has been a concentrated effort to “push” this change before the next revision to NFPA 1901. The new proposed NFPA standard “realignments” has put a damper on this wished-for change if not extinguishing it for the time being.

There is no intent to disparage the NFPA or any individual or entity whose intent is to make firefighters’ lives and workplaces (their fire trucks) safe. Firefighter safety should be a top priority for everyone and accolades to all who promote it. There is, however, a possibility that some individuals and entities may be overzealous in advocating changes. There is no accusation or inference some may have a hidden agenda.

Research and Testing
My interpretation of research and testing may differ from others. I believe testing should be done in a controlled environment by unbiased technicians in a systematic manner that cannot be influenced either directly or indirectly by outside sources, emotional reactions, and hidden agendas. Anything less will result, again in my personal opinion, a flawed research study or a product demonstration rather than factual scientific research that can be substantiated via recorded and verifiable data.

A Lighting Study
A study—or demonstration—was held in the parking lot at a recent regional trade show. Again, I must reiterate the reasoning for the study is not in question, nor are the qualifications of the people or entity that conducted it. A full report covering the study encompassing almost 100 pages is available at https://www.lcfa.com/clientuploads/News/Lighting_Study/Lighting_Study_Report.pdf. If the intent of the study is to strictly improve firefighter safety, I believe it is admirable. However, I do not believe it was a true scientific study that can be substantiated by factual data. As such, the results may be tarnished.

There is a video and photographs of the event as well as comments received by some people in attendance including those who participated in it and others who were in the parking lot and just wandered over to the study area. When evaluating light intensity in a certain environment, the ambient lighting in the background should be constant throughout the entire study. It was not. Another observation—not substantiated—was only one light manufacturer participated in the study. Concurrently, that manufacturer supposedly already has in place the technology and equipment to “automatically regulate” lighting intensity. That could be giving a private entity an unfair marketing advantage.

It appears the questions asked of the participants were about their “opinion” and not reflective of scientific fact. From what I understand, meters or whatever devices warning light manufacturers or testing agencies use to measure light intensity were not used. Another questionable factor was that the people asked for their opinions were all fire service related—firefighters. There are “light whackers” in the fire service who believe there cannot be enough emergency lights and lights are only intense when they cause permanent optical damage to the human eye. A more reliable testing (or study) would be, in my opinion, where John and Jane Q Public are the participants. How the general public perceives warning lights and how they react to them may be more beneficial than the possibly biased opinions of a group of firefighters in a parking lot after a long day at a trade show.

Perhaps on a scientific level, some entity could, via controlled testing, determine the intensity at which a warning light causes glare, confusion, or discomfort. And then, light intensity can be determined based upon that “scientific” analysis. A periodical covering the event stated, “There is almost universal agreement that warning lights on vehicles should be less intense at night and when stopped along the road.” I agree with that statement 100 percent and believe something should be done—scientific testing and objective analysis perhaps by third- party testing agencies. I further believe that enough time should be taken to ensure the testing, analysis, and recommended changes to NFPA 1901 are completed unimpeded by a time constraint. NFPA’s amalgamation of multiple standards into one just may give the fire service and industry enough time to do so.

BILL ADAMS is a member of the Fire Apparatus & Emergency Equipment Editorial Advisory Board, a former fire apparatus salesman, and a past chief of the East Rochester (NY) Fire Department. He has 50 years of experience in the volunteer fire service.

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  1. Any time I see a conversation on lighting, I regret not saying anything about headlights – especially when a rig is parked with the High Beams lit. For everyone’s sake, please dim your headlights when you pull up on a scene. Blinding oncoming traffic puts every person on scene in peril.

    Second: I am concerned about “light pollution”. Every dump truck, tow truck, service vehicle, etc, seems to be using warning lights all the time now. The public is tuning them all, including ours, out. I’d love to see something changed.

    Drive Defensively and Be Careful out there!

  2. Any test that is not repetable & get the same resultes isn’t a valid test. Well said.

  3. Bill Adams injects a healthy dose of cynicism into the discussion regarding effectiveness versus confusion (Dimmable Warning Lights…August 6) caused by warning lamps that are too bright (or not bright enough). His comments address the process, not the need for study. As a manufacturer of sequential-flashing road LED flares, we enthusiastically support independent scientific study of the optimum frequency, duration, and brightness of warning lamps. It is our contention, not based upon science, that the current state of technology, that is, random-flashing, short-duration (strobe-like), extremely bright warning lamps leads to drivers that are more confused, not less. Driver attention is redirected and focused on the bright lights rather than on the path ahead.

    Our non-scientific observations suggestion that lights that move in sequence require less intensity to be noticed and provide guidance rather than confusion. Runway sequential-flashing approach lights, positioned to guide pilots to the threshold, are used for a reason. During a nighttime approach, these sequential moving lights (“rabbit”) have been chosen by the FAA following extensive research. Finding a runway hidden in a “sea of light” requires guidance. Perhaps there is a message there.

    Jim Selevan, M.D.
    Pi-Lit Sequential Warning Lamps

  4. Very interesting. I would love to get Bills expert opinion on responder safety on freeways. We here at Phoenix Fire are currently looking at how we can “better” keep our members safe when operating on freeways with a single unit response. We are exploring our current SOP’s, other cities practices, as well as new technologies.

  5. Well here’s an idea for those who think that bright lights are too confusing for the general public …. we need to educate the general public to this …. if the lights are too bright so that you “can’t see,” you’re not sure what to do or where to go, how about this answer, “STOP!!!!!” Don’t continue into the emergency scene …. that’s why the flashing lights are there, to tell you to go another way. Whether the lights are too dim, too bright or just right doesn’t help the fact that too many people are too self-centered to consider that someone else might be having a worse day than they are by being inconvenienced to have to stop or detour. Until we fix society, this argument is really mute. The only thing that does have some validity is the lighting on directing traffic … if we can figure that out, that really could lead to some true assistance to safety. How bright apparatus lights are or aren’t …. not so much. The general public has no excuse for not staying away from brightly lit apparatus.

    Just my pet peeve and rant after 39 years in fulltime EMS and paid-on-call firefighter, responding in the latter capacity for almost 35 years with a 5 lane state highway through 12 miles of our first due area … and often the first emergency vehicle on scene trying to help victims and ward off those who are so obviously important that they can’t stop, but need to continue to drive into and through the emergency scene …. oh, but they do have time to gawk and take pictures (while driving). Yeah …. and we’re arguing about light intensity …. some, as pointed out in the article, with potentially economic motives.

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