This invention relates to systems, methods, and disinfecting compositions for spraying onto surfaces to be sanitized or disinfected. Methods may include providing an aqueous hypohalite disinfecting composition, and providing a spraying system that may include a hand-held spray nozzle through which the composition is sprayed during use, and a pump and associated tubing for conveying the composition to the hand-held spray nozzle. The tubing may be specifically selected to exhibit at least a 65% recovery (no more than 35% loss) of hypohalite after 24 hours of contact between the composition and the tubing. The method may further include conveying the composition from the reservoir to the spray nozzle, and spraying the composition through the nozzle, e.g., onto the target surface. A related system may include similar components. A dilute hypohalite disinfecting composition may be provided for use with the system and/or method. The system may allow interchangeable use of a quaternary amine disinfecting composition.