Fixed sites are generally located on interstate highways and at locations where individual states have invested resources to build a scale house and inspection station staffed with trained, dedicated personnel.

Mobile sites are exactly just that – mobile, and more difficult to define. They may be located at a closed rest area or may simply be a wide spot adjacent to a primary or secondary road that enforcement might occasionally use for special commercial vehicle checks. These locations may or may not have infrastructure components such as a scale or license plate reader.

The PrePass Safety Alliance Board of Directors and the majority of PrePass states continue to focus on new fixed sites and site enhancements, including the addition of weigh-in-motion scales (WIMs). WIMs weigh commercial vehicles as they travel on main roadway lanes at highway speeds, further reducing the need for qualified vehicles to pull into weigh stations. Data shows that bypassing at fixed sites continues to provide the greatest value and safety to motor carriers, enforcement and the motoring public.