The Technology and Maintenance Council recommends mounting mirrors so that the inner edges are at least 1 inch outboard of the widest portion of the load or cargo box. If they are closer than 1 inch, there will be blind spots.
Consider specifying convex supplemental mirrors that let drivers see out tandems and surrounding traffic when turning or in traffic. Deep convex hood-and fender-mounted mirrors provide awareness of hazards in some of the worst blind spots. The newest are aerodynamic to minimize vibration and loss of fuel economy.
Placement and aim are critical to mirror function. An informal Technology and Maintenance Council survey found that a significant number of trucks had their mirrors placed too far inboard. Driver vision was blocked by the front of the body or trailer, rather than allowing vision beyond the rear. The council recommends mounting mirrors so “the inner edge of the mirror is at least 1 inch outboard of the widest portion of the load or cargo box on the truck or trailer.”
Most drivers aim outside mirrors so the horizon is halfway up the mirror. This puts too much sky into the driver's field of view, and literally overlooks cars or pedestrians close to drive wheels. Aiming so the horizon is within 1 to 1½ inches (depending on mirror height) of the mirror's top edge provides better coverage of blind spots close to the sides of the vehicle.Electronic Devices: Tv Guides
No matter how good a mirror may be, its field of view will always be blocked by some portion of the body or load. For the ultimate in rearward vision, especially when backing, nothing beats television.
Many are as useful down to 0.5 lux (about ½ candlepower) as they are in broad daylight. Cameras can differentiate subtle differences in shading and eliminate light bloom, the annoying halo effect caused on TV screens by bright lights that can mask important details. Be sure to position the monitor where glare won't affect comprehension.
Electronic ranging and blind spot detection have proven their worth in fleet use over the past decade. Radar-based proximity warnings also help with backing up and lane changing. While these devices carry a high initial price, it is more than offset with lower insurance premiums due to fewer and smaller claims and a lower incidence of accidents.
Whether visual or electronic, improved driver situational awareness will pay dividends through better community relations, better image, and, of course, improved operating, maintenance, and insurance costs.
— Paul Abelson is a former director of the Technology and Maintenance Council of the American Trucking Associations, a board member of Truck Writers of North America, and active in the Society of Automotive Engineers.