Disinfection preparation kit consists of list of items used for preparation of 0.1% sodium hypochlorite solution from 0.5% sodium hypochlorite solution. The kit includes general items used for dilution of any disinfection solution. The kit can be used in health care facilities in a low, middle and high resource settings.

The solution has been adopted from WHO guidelines and Center for Disease Control and Prevention information.

The selection of disinfectant is based on the targeted microorganisms, the recommended concentration and contact time, the compatibility of the chemical disinfectants and surfaces to be tackled, toxicity, ease of use and stability of the product. Also, the selection should meet local authorities’ requirements for market approval, including any regulations applicable to specific sectors.

Hypochlorite-based products include liquid (sodium hypochlorite), solid or powdered (calcium hypochlorite) formulations. These formulations dissolve in water to create a dilute aqueous chlorine solution to different levels of concentration. Hypochlorite displays a broad spectrum of antimicrobial activity and is effective against several common pathogens at various concentrations. The recommendation of 0.1% (1000 ppm) in the context of COVID-19 is a conservative concentration that will inactivate the vast majority of other pathogens. However, for blood and body fluids large spills a concentration of 0.5% (5000 ppm) is recommended.

Important; Hypochlorite is rapidly inactivated in the presence of organic material and therefore, regardless of the concentration used, it is important to first clean surfaces thoroughly with soap and water or detergent using mechanical action such as scrubbing or friction. High concentrations of chlorine can lead to corrosion of metal and irritation of skin or mucous membrane, in addition to potential side-effects related to chlorine smell for vulnerable people such as people with asthma.

Follow the manufacturer’s instructions to ensure that disinfectants are prepared and handled safety, wearing the appropriate personal protective equipment (PPE) to avoid chemical exposure.

Calculation of dilution procedure for liquid sodium hypochlorite concentrations

Formula

[% Chlorine in liquid sodium hypochlorite / % Chlorine desired] – 1 = Total parts of water for each part sodium hypochlorite

Ex; [0.5% Chlorine in liquid sodium hypochlorite / 0.1% Chlorine desired] – 1 = 4 parts of water for each part sodium hypochlorite

Additional information;

Bottle; 1 L plastic bottle is used to prepare the diluted hypochlorite solution. The volume of the selected bottle is based on the final volume of the diluted solution.

Measuring cylinder; Measuring cylinder is used to measure required volume of hypochlorite from the concentrated solution.

Water; Clean, non-turbid water is used to produce the final desired concentration of hypochlorite solution.

Source; WHO; Disinfection guidance & Center for Disease Control and Prevention Web information.