The label is the law. Good possibility they are just spraying fertilizer in windy conditions.
I use a ride on and above 8 makes me nervous sometimes even though the label says 15 is ok.
I carry an anemometer and speed at spray tip is usually lower than I would guess.

 

No I can assure they are not fertilizing. PreEmergent with usually roundup and 3 way combo. I get nervous as well which is why I figured I would get a general consensus

 

Which Chemlawn nozzle? The white nozzle puts out the largest droplet. Droplets fall to earth quickly. Keep the pressure at 100 lbs or less. Reduce pressure on windy days--and make sure to recalibrate in advance so your formula and windy day fill chart will be slightly different.
Be ready to explain this if the Dept of Environmental Quality wants to talk.
The green nozzle and yellow nozzle have smaller openings--and therefore smaller droplets. These small droplets are more likely to drift. Make sure you have a white nozzle in your glove box.

On the other hand--nozzles with only one hole produce small droplets--these are more likely to drift. Keep these low--near the ground. Avoid high pressure.

Naturally, do not take chances. Keep back from flowers and vegetable plantings. Tomatoes and grapevines are very sensitive.

Make sure you replace any injured flower immediately with a profuse apology--plus the next application is free. Otherwise the customer will soon be gone.

 

Do you see the pro lawn sheilded sprayers out at all just curious?

 

Man, never seen one in person but I think the concept is great. But you can't monitor for problems and they're a bit bulky. Been thinking about a similar shield for my driveway/ roundup sprayer.

 

Thought that may be the case. They are bulky on small lawns. I got one few years back all I use allong with back pack. Pretty easy to detect issues via spray indicator and and pressure gauge. Never had an issues besides the normal for any sprayer filters, pumps fuse once in while. Modified mine for mid mount tank on back for traction use jrco mount for sprayer portion.

They make a push battery model too as I recall not sure how hard it would be to push.