Are there any requirements for how many and how bright yellow (amber) flashing lights are to be on work trucks?
Specifically, no. However, the NYS Vehicle & Traffic Law, the NYS Labor Law and the MUTCD address this topic with specific requirements. In compliance with the requirements identified the NYSDOT has issued Safety Bulletin SB-12-17, dated 3/5/12, which is based on studies published by the Virginia Polytechnic Institute and accepted by the Transportation Research Board and Federal Highway Administration (2008), and designated to uniformly address the need for vehicle visibility while engaged in highway work. Following this Safety Bulletin may be the best way to be certain your vehicles comply with the legal requirements.
This Safety Bulletin addresses the needs of lighting on work trucks, automobiles, excavators, line striping machines, etc. and visibility enhancements, including light (arrow) sticks, arrow boards, tape striping and orange flags. With regard to work trucks Safety Bulletin SB-09-01 addresses the requirements for “Pickups Trucks/Suburbans/Large Vans; Small Dump/Stake Body Trucks; and Large Dump Trucks.” Each vehicle has specific minimum requirements that should be followed.
The V&T Law and the MUTCD clearly indicate that these types of lights do not refer to the manufacturer installed vehicle hazard warning flashers. Legal text addressing the requirements is as follows:
NYS Vehicle and Traffic Law: Section 375.42.3: “one or more amber lights may be affixed to a hazard vehicle, and such a light or lights which display an amber light visible to all approaching traffic under normal atmospheric conditions from a distance of five hundred feet from such vehicle shall be displayed on a hazard vehicle when a vehicle is engaged in a hazardous operation.”
MUTCD 2009 Edition: refers to “high-intensity rotating, flashing, oscillating, or strobe lights” in several places on when they should be used, but not in a specific number per vehicle or brightness per light…
NYS Department of Labor Law: Section 23-1.33 (c)4: vehicular protection; Where a temporary roadway is designated or constructed, adequate warning signs, flashing lights, flagmen or other means shall be provided to indicate clearly the paths of vehicular travel.
Section 375.42.3, Vehicle and Traffic Law of the State of New York, 2012 Edition (Select “Laws of New York”, than VAT Vehicle & Traffic)
Temporary Traffic Control, Part 6, Manual of Uniform Traffic Control Devices, 2009 Edition (PDF)