well here is what rep from their company says.......
my name is Brad and I am with Siamons International, the manufacturer of Concrobium Mold Control®. I thought it might help if I addressed your questions directly.
Your first question is whether Concrobium Mold Control just "encapsulates" mold, which implies that the solution just "covers" or "traps" the mold. Some antimicrobial solutions are just 'encapsulants', but Concrobium Mold Control goes further than encapsulation; as it dries over the moldy surface it forms an antimicrobial shield that actually eliminates the mold and mildew underneath.
Your second question regards the need for re-application. In addition to eliminating mold, Concrobium Mold Control stays on surfaces – in the form of an invisible antimicrobial shield – to prevent mold and mildew growth. As long as that shield is intact, the treated surface retains a protective barrier that will prevent the growth of mold and mildew. Reapplication is only necessary if that barrier is removed or covered with a new surface. So if the surface receives constant dousing with water (e.g. a shower stall), or resurfaced (painted) or becomes very soiled, it is recommended that the Concrobium Mold Control be reapplied. Otherwise reapplication should not be required.
Your third question regards the ingredients of Concrobium Mold Control. You are correct that the solution is 0.95% sodium carbonate, but there are two other ingredients which, combined with the sodium carbonate and the water, result in this unique, patented solution that eliminates and prevents mold. The solution contains no bleach, ammonia or VOCs. Our Material Safety Data Sheet is posted on our web site:
http://www.concrobium.com/US/advantage.html.
Your final question asked whether the product is EPA-registered or EPA-approved. The answer is the former: Concrobium Mold Control is EPA-registered, which means that our science has been reviewed by the EPA and that we are allowed to make the claims that the product eliminates and prevents mold. Note that any manufacturer who claims that their product eliminates or prevents mold WITHOUT EPA registration is breaking the law. To the point about EPA "approval", it is our understanding that the EPA does not "approve" or "endorse" antimicrobial products, so "registration" is the only term that applies in this situation.