Hydrogen peroxide decontamination

Hydrogen Peroxide Decontamination Overview

When cleaning your modular cleanroom environment or other work areas requiring standards of sterility, the quickest and most effective way to inactivate microorganisms and other pathogens is by hydrogen peroxide decontamination.  Hydrogen peroxide decontamination, also known as VHP or vapourised hydrogen peroxide decontamination, is used in industries whereby aseptic manufacturing procedures are used to sterilise a product or environment, such as in critical care and isolation wards in hospitals, pharmaceutical cleanrooms, operating theatres, fermentation suites, and research labs.


Hydrogen Peroxide Vapour

Vapourised hydrogen peroxide is a solution of water and hydrogen peroxide designed to decontaminate by coating surfaces and objects in an ultra-thin layer of micro-condensation of hydrogen peroxide vapour, undetectable to the naked eye.  When passed over a vapouriser the liquid solution becomes a vapour in concentrations of 140 – 1400 parts per million.  The vapourised hydrogen peroxide is left to circulate throughout the cleanroom or closed environment for a set period of time, after which it is broken down into oxygen and water via a catalytic converter.

The micro-condensation left by the hydrogen peroxide vapour provides optimal inactivation conditions for microorganisms.  Using high velocity gas distribution nozzles and a vapour generator, all objects and surfaces within a cleanroom or clean environment are exposed uniformly to the hydrogen peroxide vapour.

As vapourised hydrogen peroxide naturally biodegrades into water and oxygen, it’s considered to be “residue free” and one of the most environmentally friendly methods of decontamination out there. Once cleanroom airflow and natural biodegradation have dropped hydrogen peroxide vapour levels within the environment to a level safe for humans (< 1ppm) personnel can resume cleanroom functions.


The Benefits of Hydrogen Peroxide Decontamination

Aseptic processing cleanroom environments utilise hydrogen peroxide decontamination procedures in order to sterilise the environment without causing potential damage to products through radiation decontamination.  This is especially true of the pharmaceutical industry, where radiation could potentially denature samples and medications.  Hydrogen peroxide decontamination offers a safe method of sterilising a cleanroom without the use of radiation.

  • Safe.  Hydrogen peroxide vapour produces no noxious fumes and naturally biodegrades into harmless molecules, making it safe for use and transport.
  • Fast.  Hydrogen peroxide decontamination is effective against a wide variety of pathogens such as spores and fungi, viruses, bacteria, as well as MRSA and is capable of reducing these contaminants below detectable levels within minutes.
  • Environmentally friendly.  Hydrogen peroxide vapour biodegrades quickly and naturally, forming oxygen and water as a by-product.  It is considered “no residue” and non-polluting.
  • Compatible.  The process of hydrogen peroxide decontamination does not damage surfaces or equipment within a cleanroom or clean environment, allowing personnel to return quickly and easily after decontamination.
  • Effective.  Hydrogen peroxide decontamination easily inactivates the following cleanroom contaminants:
  • Aspergillus Expansum
  • Aspergillus Niger
  • Aspergillus Parasiticus
  • Aspergillus Restrictus
  • Aspergillus Sydowii Cladosporium
  • Bacillus
  • Bacillus Atrophaeus
  • Bacillus Stearothermophilus
  • Bacillus Subtilis
  • Cladosporiodes Type 1
  • Cladosporium Cladosporiodes
  • Cladosporium Sphaerospermen
  • Escherichia Coli
  • Penicillium Atramentosum
  • Penicillium Chrysogenum
  • Penicillium Citrinum
  • Pseudomonas
  • Pseudomonas Aeruginosa
  • Salmonella Choleraesius
  • Serratia Marcescens
  • Staphylococcus Aureus
  • Stachybotrys Chartarum
  • Trichophyton Mentagrophyte
  • Virus Bacteriophage P22 HT 105


Hydrogen Peroxide Vapour Versus Aerosol Hydrogen Peroxide

Due to the uniform application procedure of hydrogen peroxide vapour, the vapourised method has a track record of more than 6-log uniform pathogen reduction in clinical trials, whereas aerosol hydrogen peroxide systems perform inconsistently, with results of 4-log pathogen reduction or lower.  What’s more, aerosol hydrogen peroxide systems are usually installed within the room and stationary, leading to incomplete and non-uniform distribution of the decontaminant, as well as varying levels of pathogen inactivation throughout the enclosed space.

C.difficile, as example, is a resistant pathogen found in hospitals.   Studies show that aerosol hydrogen peroxide systems manage an 85-89% elimination of C.difficile, while hydrogen peroxide vapour decontamination results in 100% elimination.    In addition, hydrogen peroxide vapour has an even distribution, short cycle time, and is consistently reliable, making it the obvious choice for bio-decontamination.


Using Enzyme Indicators to Test Hydrogen Peroxide Decontamination Efficacy

While biological decontamination with hydrogen peroxide vapour makes sterilisation quick and easy, testing the efficacy of your sterilisation procedure isn’t as fast.  Using traditional biological indicators, cleanroom operatives can expect to wait as long as a week for culture results to come back from the lab.  Protak Scientific is looking to change the way cleanroom sterility is tested by making it faster, more accurate and more cost effective.

Enzyme indicators, developed from the isolated thermostable enzyme Adenylate Kinase (found in the bacteria Supholobus acidocaldarius), are able to provide instant, quantifiable results on your sterilisation protocol.  Adenylate Kinase undergoes a luciferin reaction which emits light, enabling measurable results of microorganism inactivation.  And the results are immediate, which means no longer needing to halt cleanroom operations following sterilisation. Making it the perfect partner to hydrogen peroxide decontamination procedures.

Protak Scientific is currently testing their new enzyme indicator in commercial trials, and looks forward to bringing this new technology to the scientific community.