Chapter 12: Protection of Vacuum Systems
Experimental procedures involving radioactive and/or bio-hazardous materials frequently require the use of building vacuum systems or vacuum pumps. Such procedures can result in the accidental contamination of the vacuum system or laboratory pump with hazardous aerosols or fluids. The vacuum system or laboratory pump must be protected with a secondary reservoir and disposable filter assembly when this possibility for contamination exists.
The secondary reservoir consists of a side arm flask with plastic tubing running from the experiment to the lower arm of the flask. A second tube is connected to the upper arm of the flask and to the inlet port of the disposable filter assembly. The outlet port of the filter is connected to the vacuum source with a third tube. Ideally, the flask should be placed higher than the experiment so that liquid accidentally aspirated into the flask can drain back to the primary reservoir when the connection at the vacuum line is broken. The filters should have a rated capacity to remove particles .45 um or larger.
Filters potentially contaminated with biohazards shall be autoclaved before disposal. Filters contaminated with radioactive material shall be disposed of with other radioactive waste.
The disposable filter assembly can be purchased from Fisher Scientific, part number 09-744-75 or 09-744-76, or available equivalent.
Fume Hood Safety
Fume hoods must be individually authorized by Radiation Safety and posted with a radiation warning sign before using radioactive materials in them. Each approved hood must have a minimum airflow face velocity of 100 linear feet per minute. All radioactive materials use hoods are inspected annually by EHS’s Collaborative Laboratory Inspection Program (CLIP) for adequate face velocity. Any hood that may not be in proper working order or having an inadequate face velocity should not be used. Promptly report any problems to the EHS.