Decontamination of High-Containment Laboratories for Demolition: A Risk-Based Approach.

Introduction: Decontamination of redundant laboratories, contained plant space, and support buildings used to handle high consequence animal pathogens (North America BSL-3Ag, UK SAPO4) was required before demolition to mitigate the risk that infectious material was released into the environment.

Methods: Given the age of the buildings and their construction, bespoke qualitative risk-based methods were developed by biorisk personnel, in consultation with specialist contractors where applicable. This approach was to give assurance that suitable decontamination was achievable, sometimes through multilayered approaches to disinfection.

Comparing the Efficacy of Formaldehyde with Hydrogen Peroxide Fumigation on Infectious Bronchitis Virus.

Background: The recent reclassification of formaldehyde as a presumed carcinogen prompted the investigation into the comparative efficacy of hydrogen peroxide as a fumigant in microbiological safety cabinets.

Introduction: The aim of the study was to quantify the biocidal efficacy of formaldehyde fumigation, including variables such as exposure time and concentration, and then to compare this to the biocidal efficacy achieved from a hydrogen peroxide vapor fumigation system. The study also investigated the ability of both fumigants to permeate the microbiological safety cabinet (MBSC), including the workspace, under the work tray, and after the HEPA filters.

Biological Validation and Observations of Formaldehyde Fumigation in Operational and Representative Scenarios in High-Containment Laboratories.

Introduction: The effectiveness of formaldehyde as a fumigant in laboratories, for equipment, and for containment barrier decontamination applications was assessed, in particular the ability to reproduce biological inactivation (6-log reduction) of commercially available rapid biological indicators in representative operational scenarios and their relative sensitivity to other biological and chemical indicators.

Objectives: The primary objective of this study was to describe observations and results of formaldehyde fumigation efficacy in high-containment laboratories.

Results: Biological indicators placed throughout laboratory spaces, including ventilation ductwork at distances up to 15 meters, inside pieces of equipment and in lengths of pipe, were mostly negative, demonstrating the ability of formaldehyde to reach the interior and external surfaces tested.