Avoiding aerosols from Alcohol-based hand rubs

Nearly all healthcare professionals in the modern era come into regular contact with alcohol-based hand sanitizers as part of their hand hygiene program. In some instances, these liquids are atomized through the integration of spray pumps in a dispenser. While this has the advantage of ensuring wider coverage on hands, this typically leads to increased formation of aerosols that can enter the respiratory tract.

We inhale aerosols constantly – these fine particles lurk in our ambient air and are produced by mechanical or thermal processes within our work and home environments. Aerosols are liquid or solid particles dispersed in a gas – usually air – and typically only measure a few nanometers in diameter. A typical example might be the soot created from engine combustion – something that has been shown to have a negative impact on human health. Airborne micro particles are regularly produced in healthcare environments, which can cause sustained irritation of the upper and lower respiratory tract when exposure is significant. This includes the chemicals used in disinfection processes.

Why Alcohol-based hand disinfectants?

For effective hand disinfection, alcohol-based solutions are often preferred. Their antimicrobial effect is strengthened by the addition of water and a handful of other ingredients in the wide variety of solutions available on the market. Alcohols kill pathogens through the denaturation of proteins and the resulting cell membrane destruction of microorganisms. The spectrum of commonly used alcohols in hand disinfectants includes ethanol, isopropanol and n-propanol. In comparison to other disinfectants, alcohols are thought to be more skin-friendly and, in contrast to hand washing, are not associated with a significant risk of dermatosis. Most importantly, no known resistance developments are known, which makes them the optimal weapon against nosocomial infections.

Hand disinfection in healthcare facilities

In order to facilitate the frequent need for dispensing the recommended three milliliters of hand disinfectant per hand hygiene event, wall or bed-mounted dispensers with precision dosage pumps are generally used in medical clinics and hospitals. In healthcare environments, facilities can choose between many types of alcohol-based hand rubs, including liquids, gels, or foams from a wide variety of manufacturers. In some cases, liquid alcohol is combined with spray pumps in order to create an alcohol-based mist. In this way the disinfectant is distributed over the entire palm of the hand and there will be less dripping on the floor. The better handling, however, is offset by the higher presence of aerosols. The dispersion of alcohol-based liquids into fine particles means that users will inhale more alcohol particles than through a regular sanitizer pump. An intensive care nurse may record more than 100 hundred hand hygiene events per day – meaning a permanent exposure to alcohol-based particles, posing a risk for the respiratory tract.

A definite reason for occupational health and safety to take note.

Regulatory Limits

The German regulatory body for chemical risks arising from disinfectants in healthcare, has stated that aerosol-forming pumps should not be used for hand disinfection: “In addition, application procedures with aerosol formation (spray applications) should be avoided when possible.”

The exposure-risk of medical staff in clinical facilities through aerosols has not yet been investigated. Clinical studies in the field of surface disinfection show that exposure of hospital staff to hydrogen peroxide and peracetic acid increases the risk of irritation of the mucous membranes and respiratory tract. [1]

The German Research Foundation has also defined the maximum permissible concentration of various gases, vapours or particles in the air, known as MAK values. The MAK value for ethanol is 380mg/m³ in Germany. [2] Based on internal tests, typical spray solutions can create 200mg/m3 with just one 1.5ml activation.

An innovation that doesn’t mist

The PRAESIDIO® disinfectant dispenser uses a patented shower head pump to prevent the formation of unwanted aerosols. This unique technology creates a rain cone that spreads the alcohol in small droplets, rather than being turned into a mist of micro-particles. This innovation provides the benefits of a spray pump while protecting the health of the user. Drops that fall off or miss the hand, land in the integrated drip tray within the hygienic spray chamber of this touchless dispenser.

“The core requirement was to develop a dosing pump that would allow uniform wetting of the hands – but without fogging”.

– Albrecht Lang, Director New Technologies Development

The PRAESIDIO® also offers automatic, touch-free operation, thereby minimizing the risk of cross-contamination and increasing the frequency of use. A sleek window on the side of the device allows for fill level control, and its minimalist design make it a real eye-catcher. Find out more about PRAESIDIO or read a customer story.

Sources:

[1] Casey, Megan L., et al. “Health problems and disinfectant product exposure among staff at a large multispecialty hospital.” American journal of infection control 45.10 (2017): 1133-1138.

[2] MAK- und BAT-Werte-Liste 2018. DFG, Deutsche Forschungsgemeinschaft