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To NFPA 101 Life Safety Code Means of Egress Panel: Listen up!

When it comes to the illuminance requirements for exit signs, all exit signs need to be evaluated on a level playing field.  It's not as though smoke or fire near a doorway will choose to ease up because the exit sign above the door won't be bright enough for people to see.  Not to mention, ambient lighting has an adverse effect on exit sign visibility, especially in smoke.

Every exit sign needs to meet the illuminance requirements in UL 924! So why does the NFPA 101 Life Safety Code Means of Egress Panel continue to permit photoluminescent exit signs to be installed above doorways when their illuminance performance is as low as 1/10 of that of electric signs?  These signs get listed using a subjective test instead of light measurement methods. It's a failure of the safety system waiting to happen!  With that in mind, any building specifier needs to consider the recommendations of NEMA white paper LSD 46-2009 before they "go green" with their doorway exit signs.

By the way, the energy required to “charge” photoluminescent signs and maintain that charge? It exceeds that required for an LED electric sign.


Posted 02-26-2010 6:16 AM by Leibowitz, Mike

Comments

Barlow, Charles wrote re: To NFPA 101 Life Safety Code Means of Egress Panel: Listen up!
on 08-23-2010 4:41 PM

Disclaimer:  EverGlow (www.everglow.us) is a manufacturer of photoluminescent emergency lighting – code approved exit signs and exit path markings.  I am a member of the NFPA Means of Egress Committee.

Mr. Leibowitz asked NFPA and the Means of Egress Committee to “Listen up!”  He must be aware, by now, that many of those who write the standards and codes at UL, NFPA and IBC have voted to allow the use of electrical and non-electrical emergency lighting – exit signs and exit path markings.

In fact, because of the lack of reliable operation of electrical emergency lighting during emergency evacuations, the model building and fire codes REQUIRE the use of non-electrical exit path markings to supplement electrical emergency lighting in the exits of high rise buildings.

Mr. Leibowitz questions the effectiveness of photoluminescent exit signs:

a) In Smoke.  All of the data that I have seen indicates that all exit signs are not visible in smoke.  The NEMA report to which he refers shows that electrical signs are not visible after only a few minutes.

b) Green.  Of course non-electrical photoluminescent emergency lighting is green – no batteries and no lamps or LEDs; and no power consumption.  EverGlow exit signs recycle (absorb and store) the energy from normal lighting in exits and corridors leading to exits.  Mr. Leibowitz is correct that the normal electrical lighting necessary to properly charge EverGlow exit signs can consume more energy than LED exit signs.  However, he forgets that it is extremely rare for a building owner to install lighting to specifically charge photoluminescent exit signs.  If there is appropriate and sufficient normal lighting to properly charge EverGlow exit signs, and that lighting is maintained at minimum illumination levels as required by code, then photoluminescent exit signs can and do replace electrical exit signs.

c) UL924 and Level Playing Field.  Yes, every exit sign must meet the requirements of UL924.  Generally, electrical exit signs are tested to the illuminance requirement in UL924 and non-electrical photoluminescent exit signs are tested to the observation visibility test (a real world reference to luminance) in UL924.  Until exit signs become part of the overhead lighting scheme, visibility and legibility of exit signs in normal lighting and darkness are the paramount tests for effectiveness.  Generally, electrical exit signs are tested for visibility and photoluminescent exit signs are tested for legibility at a distance in darkness.

d) Ambient Lighting.  Emergency lighting must perform in normal lighting, emergency lighting only (normal electrical lighting has failed), and complete darkness (all electrical lighting – normal and emergency – has failed).  In normal lighting, both electrical and non-electrical exit signs generally are easy to see and read at a minimum distance of 100 ft.  In complete darkness, electrical exit signs have failed and are impossible to see without a flashlight directed to the sign face; only non-electrical exit signs are visible and legible.  In emergency lighting – partially lighted evacuation conditions – electrical exit signs can be seen if they have been properly maintained and their brightness is not too high (a quantity that is not tested by UL924).   Photoluminescent exit signs glow as normal in full and partial lighting.  If there is a minimum of emergency lighting, the glow of these signs will be plainly visible and legible – they are tested by UL for this quality.  If there is an abundance of emergency lighting – more than required by code – the sign face has a very high contrast that makes the photoluminescent exit sign easily visible and legible.

Photoluminescent (non-electrical) emergency lighting technology has proven to be supremely reliable and effective in all types of emergency evacuations.  Photoluminescent exit signs will continue to replace electrical exit signs where there is sufficient and appropriate normal lighting to properly charge the signs.  And, electrical LED exit signs will continue to have a place in energy efficient buildings.  Building owners and operators have two good choices for green emergency lighting.

Electrical systems wrote re: To NFPA 101 Life Safety Code Means of Egress Panel: Listen up!
on 12-20-2010 12:47 AM

Photoluminescent (non-electrical) emergency lighting technology has proven to be supremely reliable and effective in all types of emergency evacuations.  Photoluminescent exit signs will continue to replace electrical exit signs where there is sufficient and appropriate normal lighting to properly charge the signs.  And, electrical LED exit signs will continue to have a place in energy efficient buildings.  Building owners and operators have two good choices for green emergency lighting.

Electrical systems wrote re: To NFPA 101 Life Safety Code Means of Egress Panel: Listen up!
on 12-20-2010 12:49 AM

Disclaimer:  EverGlow (www.everglow.us) is a manufacturer of photoluminescent emergency lighting – code approved exit signs and exit path markings.  I am a member of the NFPA Means of Egress Committee.

terrance forma wrote re: To NFPA 101 Life Safety Code Means of Egress Panel: Listen up!
on 04-10-2011 3:03 AM

there are several choices for non electrical exit signs. Tritium or photoluminescent are the 2 that usually come to mind first. At www.emergencylights.net they carry the best of both. Not only was I able to purchase at wholesale prices, but because I referred another associate of mine to them I was able to receive a discount.

www.emergencylights.net/.../Photoluminescent-Exit-Signs

www.emergencylights.net/.../Non-Electrical-Exit-Signs

Evan wrote re: To NFPA 101 Life Safety Code Means of Egress Panel: Listen up!
on 04-10-2011 5:05 PM

In cases where there is not enough light available for a photoluminescent exit sign to properly charge and electricity is unavailable for installation of an electrical exit sign, consider a tritium powered self-luminous exit sign.

Self-luminous exit signs feature up to a 125 foot UL Listed viewing distance, 50 feet more than the longest UL approved viewing distance for photoluminescent exit signs (75 feet).

Here is some more helpful information on the differences between photoluminescent and self luminous exit signs: <a href="www.emergencylights.net/.../Glow-In-The-Dark-Exit-Signs.html">Types of Glow In The Dark Exit Signs</a>.

The website <a href="http://www.emergencylights.net"> is very helpful and informative, explaining the differences in design, construction, and application of exit signs, both electrical and non-electrical.

Keiffer wrote re: To NFPA 101 Life Safety Code Means of Egress Panel: Listen up!
on 05-31-2011 10:50 PM

That's a mold-breaker. Great thinnikg!

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