AcidBlue CH521 5 gal Low Fume Muriatic Acid. The next generation of muriatic acid is finally here! AcidBlue’s Skin Protec™ formula shields intact skin from being attacked and severely burned while the Vapor Reduction Technology (VRT)™ used in the manufacturing process produces a muriatic acid that is easier to use, store, and ship compared to standard muriatic acid. When the job requires the use of muriatic acid choose…AcidBlue.