Cleaning agents and methods

For general cleaning, detergents with a pH range 6–8 are generally appropriate.

Disposable detergent-impregnated wipes are useful for spot cleaning by clinical and other staff. There are many brands of suitable TGA-listed detergent wipes in varying sizes.

Conveniently place detergent wipes where they can be used by staff immediately when needed (eg on dressing trolleys).

The use of detergent wipes is inappropriate for cleaning larger surfaces or for general use (eg by the contract cleaner).

When a disinfectant is required, it can be used after cleaning with detergent and water, or can be used in combination with detergent when available in a suitable combined product (often called a ‘two in one’ approach).

Combined detergent/disinfectant products are available as wipes or solutions. These are suitable for cleaning and disinfecting of visibly clean surfaces, if required after spot cleaning, and for cleaning of frequently touched surfaces during an outbreak.

Disinfectants can reduce the number of microorganisms on a surface, but they are not a replacement for thorough cleaning. The cleaning process determines the effectiveness of any disinfectant.

Requirements for effective disinfection

To kill microorganisms, a disinfectant must:

• be in contact with the surface for long enough (refer to the manufacturer’s instructions)
• be used at the right concentration
• be applied to a clean, dry surface
• be effective against the particular microorganism.

Disinfectants used in healthcare settings typically have a contact time of between 30 seconds and 5 minutes for relevant microbial species. Contact time means the period for which the surface must stay wet, after applying the disinfectant solution, to achieve a 99.9% reduction in the number of relevant microbes. The effectiveness of disinfectants in practice can be overestimated for those with long contact times (eg 10 minutes), because it would be difficult to achieve this contact time without reapplying the product.²

Cleaning technique

Only use disinfects after the surface has been manually cleaned with a mechanical action; they must not just be applied to a contaminated surface. Disinfectants may fail to kill/inactivate microorganisms when the surface has not been manually cleaned or cleaning was ineffective, because they can be inactivated by organic matter and/or fail to penetrate the matter.

When using combined detergent/disinfectant solutions or wipes, the cleaning method will depend on whether the surface is visibly soiled or not, the agents in the product, and the manufacturer’s instructions for use. If the surface is visibly soiled with organic matter, a two-step process is required: clean with one wipe, then disinfect with a second wipe. This technique is required when using either a disposable impregnated wipe or a disposable/reusable cloth to apply the solution.

Disinfectants must be compatible with the surface material to avoid damage to the surface, which could compromise future cleaning.

Classification and types of disinfectants

Disinfectants are classed as low, intermediate or high level (Table 9.4. Classification of disinfectant activity).⁴

Alcohol-based disinfectants can be used on non-critical equipment (equipment in contact with intact skin), such as thermometers, tape measures and stethoscopes, after use. The surface must be clean before application, and sufficient wet contact time is required. Alcohol-based disinfectants may be available as wipes. Hazards of alcohol-based disinfectants include flammability and damage to some substances (eg rubber, plastics and glues).

Quaternary ammonium compounds have detergent as well as disinfectant properties. When used for surface cleaning on a visibly soiled surface they must be applied twice: first the surface should be manually cleaned. Then a fresh wipe or solution should be applied and the surface left wet for the required contact time to kill microorganisms. They should not be used in combination with soaps or anionic detergents because these agents can deactivate the disinfectant. Quaternary ammonium compounds can cause contact dermatitis of the hands.

Chlorine-based disinfectants such as bleach have limited application in general practices and other office- and community-based practices, but may be used to decontaminate some surfaces during a suspected norovirus outbreak. The solution should be made up just before use (1 part bleach to 9 parts water) and should stay in contact with the surface for at least 10 minutes before drying. Chlorine-based disinfectants are associated with work health and safety hazard (eg lung and skin irritation), can cause instruments to rust, bleach soft fabrics and have an unpleasant odour.

Accelerated hydrogen peroxide⁵ is widely used in healthcare including office-based practice. It is highly effective and efficient for killing or inhibiting a broad spectrum of microorganisms including yeasts, fungi, bacteria, viruses, and spores. It physically removes organisms and cleans, has rapid action requiring short contact times (1 minute), and is effective for controlling biofilm. It spreads easily across a surface and penetrates it, leaving no residue on surfaces, and is non-corrosive when used on metals. Accelerated hydrogen peroxide poses a lower risk the user and the environment than other disinfectants because it is non-irritating, non-toxic (free of volatile organic compounds), and safe for use near foods).

Emerging disinfectants and techniques such as ultra violet (UV) irradiation, hydrogen peroxide vapour and other fogging/misting technologies, steam vapour, and high-Intensity narrow-spectrum light, are not routinely used in general practices and other office-based practices.⁶ Most require special training.

Disinfectant wipes

There is limited guidance on the use of disinfectant wipes in environmental decontamination in health care.²

Disinfectant-impregnated wipes are intended for single use. Their efficacy depends on leaving a layer of liquid disinfectant on a clean surface. If rapid drying occurs, the contact time may be less than required to kill target microorganisms.⁷

Some detergent/disinfectant wipes claim activity against norovirus so it may be convenient to use these instead of chlorine disinfectants, noting the wet contact time required.

Table 9.4. Classification of disinfectant activity

*when used according to the manufacturer’s instructions

Regulation of disinfectants

Chemical disinfectants are regulated by the Therapeutic Goods Administration. Hospital-grade disinfectants that make specific claims to kill microorganisms, and disinfectants intended for use on medical devices, are required to be on the Australian Register of Therapeutic Goods (indicated by AUST R number on label).⁸ Other disinfectants not intended for use on skin or medical devices are not required to be registered, but must meet regulatory requirements (indicated by AUST L number on the label).

In response to the COVID-19 pandemic, the Therapeutic Goods Administration has also permitted manufacturers to claim a product is effective against SARS-CoV-2.⁹ A list of disinfectant products with specific claims against SARS-Cov-2 or COVID-19 on the product label is available on the Therapeutic Goods Administration website.

Items in waiting areas

In the past, practices often provided magazines and toys in the waiting room. This is no longer the norm.

Without cleaning after each use, shared or re-used toys can be a source of cross-infection between patients and should not be provided.

Magazines and books should not be provided in waiting areas. Reading matter for patients and visitors should be restricted to items that are taken away (eg brochures, fact sheets).

Electronic equipment

Staff members’ electronic devices, including mobile phones and tablets, can harbour and transmit pathogens. As it is impractical to clean these often enough to be confident they will not transmit microbial pathogens, they should be regarded as contaminated. Staff must clean their hands after touching these devices before they touch patients.

Clinically relevant pathogenic bacteria have been detected on mobile phones of hospital medical staff.¹⁰ Phones should be frequently wiped with detergent or a disinfectant and must not be handled in the toilet area.

Daily disinfection of tablet computers with isopropanol wipes has been reported to reduce microbial load.² Devices could be decontaminated following the device manufacturer's instructions and those of the cleaning agent manufacturer. Otherwise they should be assumed to be contaminated and hand hygiene practised accordingly.

Transferable clinically relevant pathogenic bacteria have been detected in dry surface biofilms on keyboards in healthcare settings.¹¹ Washable plastic keyboard covers can be used to reduce contamination and facilitate cleaning.

EFTPOS/payment terminals that are handled by staff and patients, including keyboards, should be frequently wiped with detergent or a disinfectant. Practices could use contactless terminals to reduce physical contact. Receptionists should use alcohol-based handrub after handling patients’ credit, Medicare or health fund cards.

Lanyards and neckties

Avoid wearing lanyards and neckties as they may facilitate transmission of infection.¹² If a lanyard must be worn, it should frequently be wiped with detergent or disinfectant.