IRSST - Institut de recherche Robert-Sauvé en santé et en sécurité du travail

Microbial decontamination of ventilation systems

Abstract

Ventilation, heating and cooling, and humidification systems, designed to distribute appropriately conditioned air through buildings, are also effective distribution systems for contaminants present in ambient air. Although many procedures are available for the decontamination or elimination of substrates and growth centres, their effectiveness is currently unknown. This research projet was undertaken to evaluate selected corrective measures designed to reduce the concentration of aeromicrobial flora such as bacteria and saprophytic moulds, and to verify the effective duration of such measures.

The project was conducted at a laundry which services 30 hospitals. Prior to cleaning of the ventilation system, statistically significant quantitative and qualitative differences were noted between the aeromicrobial contamination of outdoor air and the air at a number of workstations. These differences were not present in samples taken after the ventilation system was cleaned. It was recommended that the cleaning system be cleaned prior to start-up, i.e. that the air-conditioning and heating system be cleaned in the spring and fall respectively. The frequency with which the duct-work should be cleaned should be determined by visual inspection. A practical guide for end-users will be produced and published in 1993.

Additional Information

Type: Project
Number: 0088-0040
Status: Completed
Team:
  • Jacques Lavoie (IRSST)
  • Paul Comtois (Université de Montréal)
  • Van Hiep Nguyen (IRSST)