Surfaces are often underestimated as sources of contaminations and infections, although many pathogens can persist on them for several days or longer [1]. Thorough and effective surface disinfection is therefore an important cornerstone of infection prevention – especially in healthcare facilities. But which method is suitable and when: wiping, spraying, or even both?
Advantages of wipe disinfection over spray disinfection
In general, wipe disinfection should be preferred to spray disinfection for the following reasons:
- During spray disinfection, aerosols of the disinfectant are produced which can endanger the person carrying out the disinfection. This is independent whether the disinfectant is sprayed directly onto the surface or first onto a wipe. Even if the person is leaving the room immediately after performing the disinfection, the exposition to the aerosols cannot be excluded, since aerosols spread within seconds [2]. Aerosols distribute within the whole room leading to considerable dilution of the disinfectant. Therefore, inhalation of health-critical quantities is more likely with frequent spray application within a short period of time [3]. Nevertheless, aerosol formation should be kept as low as possible [3, 4]
- Wipe disinfection with working solutions of concentrated disinfectants or with pre-soaked tissues does not produce any aerosols.
- Application of foams does produce less aerosols than spray disinfection with a liquid [3]. The German Federal Institute for Occupational Safety and Health published a study in this regard in 2021: on average, inhalation exposure is reduced by a factor of 10 by switching from spray to foam for disinfection [5].
- Spray disinfection is less targeted than a wipe disinfection [6, 7]. Spray disinfection must be regarded as less effective than wipe disinfection, since spraying alone can lead to wetting gaps on the surface. Higher amounts of disinfectant are required to exclude these wetting gaps.
- Wipe disinfection is more targeted and requires a smaller amount of disinfectant
- The pressure applied during wipe disinfection on the one hand helps distributing the disinfectants evenly and on the other hand ensures better wetting of the surface without wetting gaps.
Spray disinfection in exceptional cases
According to Robert Koch Institute and the Association of Applied Hygiene, spray disinfection might be necessary in exceptional cases for surfaces which cannot be reached by wipe disinfection (e.g., hook-and-loop fasteners on blood pressure cuffs). In order to reduce the risk of health hazards and to assure effective disinfection, proper application must be ensured:
- The disinfectant should be sprayed as close to the surface as possible to minimize inhalation of the aerosols.
- If possible, foams should be preferred because of the lower aerosol formation [2-5].
- Complete wetting of the surface must be ensured [6, 7].
Conclusion
Wiping is often better than spraying. Pre-soaked wipes or foams should be preferred. Spray disinfection should be performed only in exceptional cases when the surface cannot be reached otherwise.