Title: Health and safety risk assessment methodology to calculate reverse airflow tolerance in a biosafety level 3 (BSL-3) or airborne infection isolation room (AII) environment
Authors: Farhad Memarzadeh
Addresses: National Institutes of Health, Division of Technical Resources, 9000 Rockville Pike, Bldg 13, Bethesda, MD 20892, USA
Abstract: A novel methodology is proposed to calculate how much air displacement and contaminant leakage might occur during a power outage that may result in a momentary positive pressure reversal in a BSL-3 facility. Note that the ultimate goal in design and operation of a BSL-3 facility is to achieve sustained directional airflow such that under failure conditions the airflow will not be reversed. The proposed methodology should be applied when and only when all other measures to achieve zero tolerance have been ruled out. Only after determining that zero tolerance cannot be achieved for the BSL-3 facility in question should the model be employed to perform a health and safety risk assessment to determine the reverse airflow tolerance. The methodology is applicable to other room types, such as airborne infection isolation rooms, that use sustained differential air pressure as one means to prevent particle migration across a boundary.
Keywords: health and safety; risk assessment; reverse airflow; biosafety level; BSL-3; airborne infection isolation rooms; air displacement; contaminant leakage; power outage; positive pressure reversal; differential air pressure; particle migration.
International Journal of Risk Assessment and Management, 2010 Vol.14 No.1/2, pp.157 - 175
Published online: 17 Sep 2010 *Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article