**3.1 Disinfectants for environmental surface cleaning**

For surface and environmental disinfection, hypochlorite-based compounds such as powdered calcium hypochlorite and liquid sodium hypochlorite may be used. Upon dissolution in water, these compounds create an aqueous solution of hypochlorous acid (HOCl) as the active antimicrobial ingredient. The HOCl possesses broad spectrum antimicrobial activity against pathogens. A 0.1% (1000 ppm) concentration of hypochlorite is recommended to inactivate the majority of pathogens present in the healthcare areas [66]. However, for blood and bodily fluids, a concentration of 0.5% (5000 ppm) is recommended [67]. Hypochlorite should be freshly prepared before use, because it is rapidly inactivated in the presence of environmental organic material. For better efficacy, surfaces should be thoroughly cleaned with soap or detergent, using mechanical scrubbing

or friction, before application of hypochlorite. Hypochlorite should be applied at optimum concentration, because high concentrations of chlorine may lead to metallic corrosion and irritation of skin or mucous membranes. SARS-CoV-2 deposited on HITES can be easily inactivated using chlorine-based disinfectants, detergents, iodine-containing detergents, 70% alcohol, glutaraldehyde, hydrogen peroxide compounds, halogenated compounds, various cationic and anionic surfactants, etc. [68]. SARS-CoV-2 in sewage samples can be effectively inactivated using chlorine dioxide (20 mg/L) [69]. Recently, critical information exploration on predicted and measured virucidal efficacies of several antimicrobial agents against priority viral diseases of WHO, including SARS-CoV-2, have been reviewed by Ijaz et al. [70].
