--obsolete-- Work Permit Requirement for ISAC Experiments

There is the potential to relax the radiological component of the work permit requirement for ISAC experiments in the experimental hall and at TRINAT. Once a radioactive beam tune is estabilished, a work permit, together witha requisite respiratory protection is required for the first break of the vacuum system. At that time swipes are taken and an air sample is done to estabilish the level of removable and airborne contamination. If the levels are less than 1500cpm on the pancake probe there is no further need for respiratory protection and the respiratory can be removed.

For subsequent access to the same vacuum enclosure no work permit would be needed provided the following conditions were met:

(i) the levels did not exceed  1500 cpm on the first access;

(ii) the tuned radioactive ion beam had not been changed and;

(iii) there were no longed lived isobars in the mass chain.

The presence of ling-lived isobars which could present  a contamination hazard should get noted on the safety approval for individual experiments.

In lieu of the work permit the experimenters would need to have an estabilished procedure for access. This procedure would, on every access, require contamination swipes to be taken, checked on a pancake probe and the measurement recorded in the experiment logbook.  For any measurable level of contamination, the experimenters accessing the vacuum enclosure will require a minimum of gloves.Contamination levels in excess of 1500 cpm would necessitate a respirator before continuing on with the work.