Ed, hydrogen peroxide certainly has the capability to disinfect and sanitize potable water supplies. I have a buddy in England and he states it’s done there and in other European countries regularly. I don’t think I’d recommend it for RV use however. The one thing we know about sanitizing the fresh water system in an RV using common household bleach is exactly how much to use and how long to leave it in the system (I guess that’s really two things). No one can tell me how much H2O2 to use in regards to tank capacity. Nor can anyone determine how long the mixture must remain in the system to be effective. And to what degree? The RVIA has adopted the standards as set forth by noted labs and I regularly promote the standards adopted or developed by RVIA during my teaching seminars. There are many “home brews” for many RV procedures found on the Internet, but the question remains, how effective are they?
Proponents of hydrogen peroxide often point to the advantage of it being tasteless when compared to bleach. That may simply equate to one more draining and flushing of the system when bleach is used and I’d rather side with the known stats of using bleach vice the unknowns of hydrogen peroxide. At least for now anyway.
Update! One of my seminar attendees, Scott P. sent me his comments regarding a third option for sanitizing the fresh water system. Here's what he had to say:
A quick addition to your post this week, "Hydrogen peroxide better than bleach for RV fresh water system?"
I work in the medial field as a respiratory therapist. We teach our patients to use distilled vinegar to clean
their water system on their inhaled CPAP machines. This is considered a medium level disinfectant
chemical and is not harmful to breath or drink. An added plus is that it does not harm the rubber components
of the CPAP system. Another added bonus is that it is not harmful if ingested, unlike bleach and hydrogen
peroxide. Scott P.