Simple Solutions: How to Clean Spray Tanks

By MWI Animal Health

The cleaning of spray tanks is a necessary part of equipment maintenance and is important in order to maintain good environmental practices through contamination reduction.

Empty spray tanks are not truly “empty”—they still contain pesticide residue and active ingredient. Residues can harden and clog up nozzles. Furthermore, left-over active ingredient can become a contaminate in subsequent applications which can lead to undesired results.

Three different spray tanks

The goal when cleaning out a spray tank is to dilute, neutralize and/or remove the active ingredient residue in the tank. Always wear water-proof gloves when handling pesticides. When cleaning a spray tank, follow these steps:

Triple-rinse the container immediately after use.
  1. Empty the tank/discard contents.
  2. Fill the container one-half full of water, washing down the inside surface of the container as you fill.
  3. If you are switching between products, add ammonia (1% solution), chlorine bleach (4% solution), or liquid detergent (until sudsy; best for oil-based insecticides) for a more thorough cleaning.
    Note: Do not use chlorine bleach with ammonia or any products containing ammonia, as this will produce a dangerous chlorine gas.
  4. Shake or agitate the spray tank.
  5. Drain the tank/discard contents by opening drainage valves or inverting the tank.
  6. Close drain valves and rinse twice more with water.
  7. Run water through the spray hose for 60 seconds during final rinse.
  8. Allow the tank to dry with the lid removed.
Clean any strainers with water and a soft brush.
Dispose of rinsing solution in accordance with chemical manufacturer suggestions—usually onsite as long as you do not exceed the label rate. Avoid contaminating any bodies of water.