The Rapiscan/TSA TPM-903B is designed for rapid screening of personnel in the event of a radiation release. It provides early warning of hot spots, eg. On protective clothing, and has design features suited for monitoring radiation workers, vehicles or the public. The TPM-903B is lightweight and mobile to facilitate transport to its location, where it is easily installed within seconds. In use, the aperture accommodates walkers or wheelchairs, and can be adjusted to also accommodate vehicles.