how long does hazmat background check take
1 â¢ The expiration of the HME clearance will determine how long or if we can issue you a license with HME. 2  The Transportation Worker Identification Credential (TWIC) background check will not suffice for the HME background check. â¢ 3  Adding a hazmat endorsement could affect your current license expiration date. 1. Complete the HME background check through TSA. 2  The TSA HME clearance can take up to 45 days to process, allow enough time so you can add or renew license with HME. 3  Take the HME knowledge test at a CDL/CLP office location.