Originally Posted by Too Tall
Mixing chlorine and vinegar produces chlorine gas, not a good idea
By the time you have flushed the tanks a couple of times after sanitizing with ordinary household bleach, the concentration of chlorine is down pretty close to that of almost all municipal supplies in North America. Therefore it could only produce a very negligible amount of chlorine gas. So low in fact as to be virtually untraceable. If it were a problem you would never be able to use vinegar diluted with any municipal water supply anywhere. Granted, if you were to mix straight vinegar (full strength) with full strength household bleach you would see the reaction producing the chlorine gas. The method mentioned appeared a few years ago in an Oregon RV publication. The method has been used marine industry for some time when carrying out, what is know as, super-chlorination sanitizing of ships potable water holding tanks. I have not heard of any adverse reaction.