Fire apparatus chevrons: An update
Love them or hate them, apparatus chevrons are here to stay; here's a look at how the requirements have changed and may change in the future
Some of the recent changes in apparatus marking and lighting have been met with skepticism at best and downright rejection at worst in some fire service circles. The rear apparatus-marking requirement for a chevron using retro-reflective material, which was first introduced in the 2009 edition of NFPA 1901, is just one example.
Before that, the Emergency Vehicle Visibility and Conspicuity Study was a landmark publication on how to make emergency vehicles more visible and conspicuous to the motoring public.
The report defines visibility and conspicuous as "a number of interrelated factors affecting the visibility of an emergency vehicle to approaching drivers both during a response and while parked at an incident scene. These variables include the vehicle's size, color scheme (also called a "livery"), marker lamps and retro-reflective striping, and the presence/operation of active warning devices including emergency lighting systems or audible sirens and horns.
"Conspicuity refers to the ability of a vehicle to draw attention to its presence, even when other road users are not actively looking for it."
An equally important development from that report was changes made to NFPA 1901 that specified new graphic requirements for all fire apparatus sold after January 2009. Other NFPA standards pertinent to fire apparatus, such as NFPA 1912: Standard for Fire Apparatus Refurbishing (2011 Edition), have always contained language that maintains congruency with NFPA 1901.
For example, from NFPA 1912, Chapter 5: Level I Refurbishing reads, "Fire apparatus refurbished to Level I standards shall meet the current requirements of NFPA 1901 or NFPA 1906, whichever is applicable, for those components unless otherwise specified in this chapter."
That same language is present in NFPA 1912 for Level II refurbishment. While there's no specific mandate for fire departments to bring their current fire apparatus up to the retro-reflective marking specifications contained in NFPA 1901, there appears to be no ambiguity that when a unit is refurbished it must comply with the most current applicable edition of NFPA 1901 or 1906.
The FEMA report also called for more research specific to emergency vehicle visibility and conspicuity. Based on my search, seven years after the report's original release there has been no discernable research in this area to determine, from a scientific perspective, what works and what does not.
One key findings included in the 2009 FEMA report was that it is theoretically possible to over do the use of retro-reflective materials and interfere with drivers' ability to recognize other hazards.
In a May 2016 post on the Ambulance Visibility Blog, John Killeen wrote, "Many earlier posts have described the problems associated with affixing a range of different patterned markings (especially rear chevrons) onto emergency vehicles.
"The problem is made even worse when a number of local agencies independently decide to display different pattern styles to brand their vehicles in an attempt to highlight their agency's individuality. It is only when all the different vehicles pull-up alongside one another that the full impact of the pattern confusion becomes obvious.
"Those patterns are so strong that they serve to distract the approaching motorist by drawing their eye to different areas within the emergency scene," Killeen wrote. "Keep in mind that you were stationary while viewing this image, not in a moving vehicle approaching the scene."
This untoward effect makes the outline and shape of each emergency vehicle much harder to discern. It may be correctly assumed that said driver's ability to make sense of the emergency scene is greatly reduced.
And let's not forget how this scene would present to the approaching driver at nighttime when the incident scene would be bathed in light pollution from the emergency warning lights.
The path forward
A cursory and wholly unscientific survey of fire apparatus in the greater Charleston, W. Va., area revealed a wide variety of retro-reflective markings. Some that appear to be in line with the requirements of NFPA 1901 and some that do not. The greatest variance that I've observed is in the color scheme used for the rear chevrons.
Another aspect that seems to be lacking is the application of retro-reflective markings on the sides of fire apparatus. Increasingly, fire departments are using fire apparatus in blocking schemes to protect personnel and victims while working motor vehicle crashes and other emergencies on roads and highways.
Adding retro-reflective marking to the sides of fire apparatus to improve its livery — particularly that which outlines the size and shape of the vehicle for the approaching motorist — would seem to be a good thing to improve apparatus visibility.
That's particularly true because parking the apparatus at an angle to the approaching motorist renders the rear chevron visually ineffective to oncoming traffic.
What are your thoughts on the requirements for retro-reflective markings on fire apparatus?
NFPA 1901 visibility sections
14.1.6 Any door of the apparatus designed to allow persons to enter or exit the apparatus shall have at least 96 inches (62,000 mm) of retro-reflective material affixed to the inside of the door.
22.214.171.124 A retro-reflective strip(s) shall be affixed to at least 50 percent of the cab and body length on each side, excluding the pump panel areas, and at least 25 percent of the width of the front of the apparatus.
126.96.36.199.1 The stripe or combination of stripes shall be a minimum of 4 inches (100 mm) in total width.
188.8.131.52.2 The 4-inch-wide stripe or combination of stripes shall be permitted to be interrupted by objects (receptacles, cracks between slats in roll up doors) provided the full stripe is seen as conspicuous when approaching the apparatus.
184.108.40.206.3 A graphic design shell be permitted to replace all or part of the required striping material if the design or combination thereof covers at least the same perimeter length(s) required by 220.127.116.11.
18.104.22.168 At least 50 percent of the rear facing vertical surfaces, visible from the rear of the apparatus, excluding any pump panel areas not covered by a door, shall be equipped with retro-reflective striping in a chevron pattern slopping downward and away from the centerline of the vehicle at an angle of 45 degrees.
22.214.171.124.1 Each strip in the chevron shall be a single color alternating between red and either yellow, fluorescent yellow or fluorescent yellow-green.
126.96.36.199.2 Each strip shall be 6 inches (150 mm) in width.
188.8.131.52.1 All retro-reflective materials required by 184.108.40.206 and 220.127.116.11 shall conform to the requirements of the ASTM D 4956, Standard Specification for Retroreflective Sheeting for Traffic Control, Section 6.1.1 for Type I sheeting.
18.104.22.168.1 All retro-reflective materials used to satisfy the requirements of 22.214.171.124 that are colors not listed in ASTM D 4956, Section 6.1.1, shall have a minimum coefficient of retro-reflection of 10 with observation angle of 0.2 degrees and entrance angle of -4 degrees.
126.96.36.199.2 Fluorescent yellow and fluorescent yellow-green retro-reflective materials used to meet the requirements of 188.8.131.52 shall conform to the minimum requirements specified for yellow Type I sheeting in ASTM D 4956, Section 6.1.1.
184.108.40.206.3 Any printed or processed retro-reflective film construction used to meet the requirements of 220.127.116.11 and 18.104.22.168 shall conform to the standards required of an integral colored film as specified in ASTM D 4956, Section 6.1.1.
19.18.11 Where the design of the aerial device incorporates a knuckle, the knuckle shall be as follows: (1) equipped with position lights or continuously illuminated by boom lights. (2) Painted with reflective paint or provided with retro-reflective striping
22.214.171.124 All stabilizers that protrude beyond the body of the apparatus shall be striped or painted with retro-reflective material so as to indicate a hazard or obstruction.