Typically, unused materials are carried over to the next striping job. However, situations often arise that require a test spray or a complete flush of the kettle and guns. Contractors often perform test sprays prior to thermoplastic striping to warm up the guns and verify that the guns are spraying properly. In addition, contractors often flush out their kettle and guns when switching to material of a different color or after finishing for the day.

Inspectors should verify that contractors are properly disposing of marking materials when performing test sprays or flushes. Although not a standard requirement, some districts

require

that contractors collect all excess striping material into a pan instead of spraying on the ground.

Contractors will often capture flushed-out paint material for re-mixing with new material, which is allowed only if detergents are not used. Two-component materials should never be reused once sprayed.

Flushing of the entire truck should not be allowed at the job site for any material. Contractors are also not allowed to dispose of any material into storm sewer drains.