If did not use 2 4 d, A triple rinse should work that complete triple rinse. If did use 2 4 d, I get new sprayer.

I have never worried about it. I usually just use my sprayer for Roundup, but occasionally need it for bug killing or oil spray or whatever. I just rinse it out with three small changes of water that includes spraying to clear the hose and sprayer tube.

Remember the solution to most pollution problems is dilution.

If you have a 1 gallon, 128 oz, sprayer, and assuming the solution you spray is 1% of the toxic material and you have left one 1 oz of the 1% solution in the sprayer.

On the first fill of another 128 oz. of water, the resulting solution has been reduced to 0.0078%. You then empty the container and add another 128 oz. The second solution is now 0.000061%. You do this a third time and it is reduced to 0.00000047%. This is a less that 1ppm of the original solution. or the toxic solution is less that 10 ppb. While my math may have an error, you can see where it is going.

To be sure the toxic material is out, check the MSDS sheet and continue the rinsing until the Toxic material is less than the lethal doses shown on the MSDS sheet.

To be sure you may wish to add a little surfactant (soap) to each dilution.

Agree with all comments. Don't know about up your way, but you can get a gallon pump sprayer in the states for about $10, TSC, etc. I'd just get another one for spraying liquid fertilize and misting and keep the other for weed control. I think I now have about four in the barn, suitably labeled. :-)

Your description and others are already correct, but if you do have more concern, it's good to get another one, too.

Try a different brand to see what might be different, if you had thoughts that the one you are using wasn't good enough.