New York State Department of Transportation 12/14/2010.

LED SNOW PACK

New York State Department of Transportation

12/14/2010

Problem Description• With the installation of low wattage LED

traffic signal modules replacing 135-150 Watt incandescent lamps, there is insufficient heat created by the LEDs to prevent snow from sticking to the lens of the LED modules.

• The problem generally occurs with wind driven wet snow. Which tends to stick to the lens surface. Colder, dry snow does not stick to the lens.

New York State - Current Practice

• Intersection is placed into ALL RED (we use the stop timing switch, catching a all red timing interval)

• Traffic Signal Maintenance vehicles are pulled into the intersection to block traffic.

• Personnel quickly remove packed snow with long paint roller extensions equipped with a brush.

• This process takes less than 2 minutes.

LED Lenses with Snow Pack

Note signal in “All Red” and vehicles in intersection

Lenses Cleaned of Snow

Brush Attached to Extension

Paint Extensions Used

Other Solutions Tried in NYSDOT Snow Scoop Tunnel Visors. These

devices provided no noticeable benefits, and in some cases resulted in additional snow stack on top of the hoods.

Pressurized windshield washer fluid. This was useful to remove packed snow but it didn’t prevent snow from sticking on lenses.

Use of Rain-X?

Greetings from New York!

As you can see, snow pack is not the only problem in New York….