Read the pesticide label and have the recommended cleaning solution on hand. Dilute the cleaning solution according to label recommendations. Choose an area to clean the tank that will not cause rinse water to contaminate streams, lakes or other water supplies. Keep rinse water away from children and pets. Make sure the rinse runoff will not flow to an area with susceptible plants or vegetation.
Wear the same protective equipment used for application, with the addition of goggles and a chemical resistant apron. Rinse the outside of the tank with water. Fill the tank with water to about 10 percent capacity and use the sprayer to empty the tank in an area that the label says the pesticide can be used. Repeat a few times to remove as much pesticide as possible.
Use the selected cleaning agent to clean the outside of the tank. The tank does not need to be filled, but use enough cleaning agent to fill the sprayer and hose. Run the cleaning solution through the sprayer to clean it thoroughly.
Inspect the tank while still wearing protective gear. Look for cracks or leaks and also check the condition of the hose. Check the sprayer nozzle for damage or wear.
Disassemble the sprayer for storage. Store components in a marked container in an area that children and pets do not have access to, since small amounts of pesticide residue may remain even after cleaning.