From Hardi
It's good practice to clean the sprayer immediately after use. A clean sprayer is safe, won't be damaged by residues, is ready to use and you avoid crop damage.
Cleaning starts by reading and understanding the pesticide label and sprayer cleaning instructions, before you start spraying. Some pesticides require specific deactivating agents or cleaning procedures. Some pesticides like sulphonyl ureas are extremely active, even at very low concentrations.
Protect your farming tools, your health and your crops by cleaning the sprayer properly.
From AgPhD Iron Talk
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