An accurate platform scale is the heart of a roadside truck weigh station.

If you were responsible for enforcing the weight regulations for traffic on public highways, you’d want to set up measurement stations and then spell out requirements for those stations.  The Washington State Department of Transportation is in just such a position, which is why they published requirements for installing and maintaining platform scales at their vehicle weighing stations. The scales are required to be “accurate to within one-half of one percent of the correct weight throughout the range of use;…[be] arranged so that operators and inspectors can safely and easily see the dials, beams, rods, and operating scale mechanisms;” and be “carefully maintained.”