Spun glass air filters for bacteriological cabinets, animal cages, and shaking machine containers
Decker, H.M.; Geile, F.A.; Harstad, J.B.; Gross, N.H.
Journal of Bacteriology 63(3): 377-383
ISSN/ISBN: 0021-9193 PMID: 14927569 Accession: 013836195
A practical, compact, spun glass filter unit having a capacity up to 250 cu. ft./min. has been developed. Tests were performed using Serratia indica and Escherichia coli bacteriophage T-3 as bacterial and viral simulants to determine the filtration efficiency of the unit containing 2 layers of spun glass. The avg. minimum efficiency obtained when testing this unit exceeded 99%. This efficiency will permit the discharge of air originally containing infectious bacteria and viruses to the outside atmosphere except when there are several million organisms per cubic foot of air. However, filtration efficiencies of 99% cannot be considered adequate when the air is to be recirculated. A method of decontaminating the filter unit in place with dry heat sterilization is described. Time and temp. relationships for satisfactory decontamination are given. An animal cage having a spun glass filtered air supply has been developed. Use of this cage may prevent cross-contamination and avoid release of pathogens to the atmosphere. A container for flasks used on shaking machines is described which completely encloses the flask, yet provides through a spun glass filter sufficient air for satisfactory bacterial growth.