Firstly, let’s clarify what the difference is between cleaning, sterilisation and disinfection.
Cleaning involves merely removing soil from a surface. This usually includes the use of water and detergents.
Sterilisation involves destroying all microbial life on a surface, and usually occurs separately after cleaning. The use of chemicals, pressurised steam, dry heat, and hydrogen peroxide gas plasma are all examples of sterilising agents used in health care.
Disinfection is the process of removing all pathogenic microorganisms from the surface, except bacterial spores. Disinfectants are further categorised as being low-level, intermediate-level, or high-level.
In the ambulance environment it’s best to use a combined method that involves cleaning, disinfection, and sterilisation all together.
Items that should be cleaned and disinfected with intermediate-level disinfectants include surfaces such as countertops, cupboards, walls, floors, and ceilings within the ambulance.
A chlorine-releasing agent such as sodium hypochlorite solution (bleach) is a classic example of an intermediate-level disinfection chemical. In sufficient concentrations and with enough contact time, bleach will disinfect surfaces of infections such as the human immunodeficiency virus (HIV) and Hepatitis B.
Good examples of locally available intermediate-level disinfectants are SteriTech Concentrated Antimicrobial Solution (CAS) and SteriTech Disinfecting Cleaner.
Items that should be cleaned and disinfected with high-level disinfectants include patient contact items such as laryngoscopes, stethoscopes, mattresses, blood pressure cuffs, splints, scoop stretchers, defibrillation paddles, spider harnesses, and head blocks.
High-level disinfectants are far more reliable at disinfection of a wide range of pathogens, and in a much shorter time than intermediate-level disinfectants. Good examples of locally available high-level disinfectants are Prodis XP which contains glutaraldehyde and ammonium chloride, and SteriTech High Level Disinfectant.
In addition to cleaning and disinfection, certain items such as laryngoscope blade and handles should be fully sterilised using methods such as pressurised steam.
Consideration should also be given to disinfecting the interior air and surfaces of ambulances using ultraviolet radiation (UV) exposure. The SANI 18 Ambulance Unit is a local product that offers such functionality.
Ambulance services should also strictly ensure that items such as cloths and mops used for cleaning ambulances and equipment are regularly disinfected and replaced.
A comprehensive guideline document on the cleaning, disinfection and sterilisation of healthcare equipment is available from the Centers for Disease Control and Prevention (CDC), at the following link: http://www.cdc.gov/hicpac/Disinfection_Sterilization/3_4surfaceDisinfection.html