The disinfection of equipment and surfaces is a critical component of safe and effective animal research, as required by most international standards and regulations.
Q: WHAT IS THE BEST CHEMICAL FOR OPTIMAL DISINFECTION?
A: H2O2 (HYDROGEN PEROXIDE)
Hydrogen peroxide is an antimicrobial chemical, used widely in both liquid and gas form, for disinfection and chemical sterilization applications. Using H2O2 provides:
- Potent and broad-spectrum antimicrobial activity
- Availability of high-stability solutions with long shelf-life
- Increased safety for users, animals, and the environment, in comparison to other microbicides, when used in secure concentrations and / or conditions
For these reasons H2O2 is used in many products and for many applications in healthcare and biomedical research facilities. In addition to its comparative safety, it fares better in other ways against the following microbicides, which can have these disadvantages:
- Alcohol: Is neither a sterilant nor a high-level disinfectant. Its quick evaporation does not allow for significant Log reduction
- Chlorine: Corrosiveness to metals, inactivation by organic matter, and relative stability
Q: WHAT IS THE BEST FORM OF H2O2 TO USE FOR ASD?
A: DRY FOG (ULTRA FINE DROPLETS < 10 µm)
H2O2 droplets generated after dry-fogging behave as a gas, permitting its use for highly effective Airborne Surface Disinfection (ASD), even at lower concentrations (7-10%). These low-concentration, micro droplets generated through dry-fogging have become a popular alternative to other chemical- and physical-based antimicrobial methods. Indeed, this:
- Uses 100% of their active ingredient, resulting in very high efficiency
- Relies on ready-to-use products
- Is available in pure solutions with no additives, resulting in no residue
- Operates at normal (room) temperature
- Is secure because of its low concentration
- Is non-corrosive
- Has a sufficient H2O2 concentration which permits optimum penetration into microbial cells
Q: WHAT H2O2 DIFFUSION TECHNOLOGY IS PARTICULARLY SUITABLE?
A: DRY FOGGING
Dry fogging diffusion (ultra-fine droplets, calibrated 5-10µm) is the simplest, most suitable, and efficient method for multiple ASD applications in animal research due to the following:
- Full diffusion of droplets before gravitation
- H2O2 behaves like a gas after vaporization, i.e. spreads homogenously in all volumes, reaching even inaccessible spots
- Diffusion at room temperature does not micro-condensate on colder surfaces as high-temperature steam does before reverting back into vapor phase
- Effective for the disinfection of electronic devices, fabrics, and paper
- No necessity for empty, or sealed rooms
- Does not employ compressed air or ultrasonic technology
- Rapid efficacy (much shorter evaporation time)
- Technology allows for portable, user-friendly, remotely-controlled, and cost-effective systems
Not for use in USA, not EPA Approved
References:
ILAR Guide for the Care and Use of Laboratory Animals (2011)
The Use of Hydrogen Peroxide for Disinfection and Sterilization Applications, Gerald McDonell, April 2014. Link
Guideline for Disinfection and Sterilization in Healthcare Facilities, CDC, 2008. Link