Again, if you are using chemicals that eat metal, can etch glass, and are deadly if employees or customers come in contact with them, its time for you to get out of the car wash business and find another line of work. If your customers knew you were using these products on their vehicle, they would not come back. If you're operating on the up and up perhaps its time to alert your local newspaper or TV stations if you know of those who use these chemicals on people's cars. There is no place for HF in this industry.
If we permit some to use it then we are guilty by association. Its time for the industry to do some policing of its own.
Again, most operators who use HF do so not because it works, rather because it works and its because it is CHEAP, without regard for its possible consequences.
Oh, and its easy to tell when someone is using it because of the odor and the burning of eyes and nose. Its hard to imagine operators exposing their employees to HF and similar products. When they have a Worker's Compensation claim (and they will eventually) they will also face a civil suit and possobly even criminal charges as well.
Its amazing how some people can sleep at night!