Biodecontamination Services and Consultancy in Aseptic Processing and Biosafety

Vaporized hydrogen peroxide (VH₂O₂) biodecontamination is an automated process used in the pharmaceutical and biotechnology industries to achieve controlled reduction of microbial contamination in critical environments.
VH₂O₂ can be generated using:

• Hot generation (flash vaporization): vaporization of a concentrated H₂O₂ solution injected into a heated air stream.
• Cold generation: atomization or nebulization of the liquid biocide, producing a fine fog.

Both technologies enable homogeneous distribution of the decontaminating agent when the process is properly designed and validated.

It is not a cleaning process and does not replace prior cleaning. Cleaning removes visible dirt and residues, while biodecontamination acts exclusively on microorganisms and must always be applied to previously cleaned surfaces. Although the terms disinfection and biodecontamination are sometimes used interchangeably, biodecontamination generally refers to automatic, reproducible, and validated processes applied to entire volumes such as rooms, SAS, or isolators.

Automatic VH₂O₂ biodecontamination allows reproducible microbial reductions of up to 6-log, even against highly resistant microorganisms. This level of efficacy is difficult to guarantee with manual disinfection, as it depends on application technique, contact time, and operator consistency. VH₂O₂ microcondensation results in high surface concentrations, explaining its strong microbiological efficacy and broad spectrum of action.

No. It is a bi-phasic process, involving both vapor/gas and liquid phases. During the cycle, subvisible microcondensation forms on surfaces. This microscopic liquid phase, rich in H₂O₂, is the primary mechanism responsible for microbial inactivation.

Visible condensation is undesirable, as it may dilute the biocide and affect materials. In contrast, subvisible microcondensation is necessary and desirable, as it enables rapid and effective microbial inactivation. The objective is to control condensation, not to eliminate it completely.

Relative humidity, together with temperature and material characteristics, directly influences:

• microcondensation formation,
• the amount of H₂O₂ deposited on surfaces,
• and overall process efficacy. rgba(117,196,213,0.09)

Each VH₂O₂ technology defines specific operating ranges, and cycles must be designed accordingly to ensure robust and repeatable results.

VH₂O₂ biodecontamination does not follow a classical time/concentration model.
Efficacy mainly depends on:

• proper microcondensation formation,
• homogeneous agent distribution,
• and local surface conditions.

Increasing exposure time or gas-phase concentration alone does not guarantee higher efficacy.

Yes, as a process control parameter, but not as a direct indicator of microbiological efficacy. Microbial inactivation mainly occurs in the condensed liquid phase on surfaces, which is not directly reflected by airborne concentration measurements.

Validation is performed using:

• Biological indicators (BIs) placed in representative and worst-case locations.
• Chemical indicators as qualitative confirmation of distribution.

There is increasing use of enzymatic indicators, which provide quantitative data and immediate results, as a complement to traditional validation approaches.

No. In automatic and terminal biodecontamination, rotation is not required. VH₂O₂ is a broad-spectrum oxidizing agent, and no microbial resistance has been documented when it is properly applied.

Yes. VH₂O₂ is generally compatible with most materials used in pharmaceutical environments. It decomposes into water and oxygen, leaving no residues. Final compatibility depends on the material, cycle frequency, and process conditions, so specific assessments are recommended for critical applications.

Yes. VH₂O₂ systems operate in closed volumes and include controlled aeration phases that reduce concentrations to safe levels before re-entry. Once the cycle is completed and aeration is confirmed, areas can be safely reoccupied without residual exposure risk.