There's a standard for everything. Really. Quality Digest's ever vigilant editors came across this relatively new one from ANSI. By the time this horse is tricked out with lights and signs its going to look like the Borg.
--Editor

From an ANSI news release:

Seeing a horse and a buggy can evoke romantic memories, but the merging of high-powered vehicles with animal drawn equipment in urban centers or on public roadways creates potentially hazardous situations requiring special safety procedures.

A recent standard, ANSI/ASAE EP576.1 JUL2008—"Lighting and Marking of Animal Drawn Equipment," from the American Society of Agricultural and Biological Engineers (ASABE) establishes a unique identification system for slow-moving animal-drawn vehicles, such as Amish buggies, horse-drawn farm wagons, and urban carriages on public roadways or highways.

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