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SUMMMARYThe effect of operating clothing on the dispersal of bacterial particles from the wearers was studied in a dispersal chamber. A comparison was made of six gowns as well as four types of trousers. The gowns were of three basic types, namely a conventional cotton type, disposable types made of non-woven fabric and those of the total-body exhaust system (Charnley type). The dispersal chamber could simulate conditions as expected both in down-flow unidirectional ultra-clean systems and in a conventional turbulent plenum-ventilated system. It was found that the disposable gowns would reduce the dispersal rate by about 30 % in the simulated conventionally ventilated system and about 65 % in the laminar flow system. The total-body exhaust system (Charnley) would reduce the count by 10-fold in the conventional ventilated system and by 66-fold in the laminar-flow system.The poor performance of the gowns in conventionally ventilated systems was caused by the dispersal of bacterial particles from underneath the gown (about 80 %). This was not reduced by the disposable gown and only partially by the Charnley type. This small drop would be further decreased in a conventionally ventilated operating-room as only scrubbed staff would wear the gown. In order to overcome this poor performance in conventionally ventilated operating-rooms impervious trousers would be required. Four types were studied and it was demonstrated that those made either from Ventile or non-woven fabric would reduce the bacterial dispersion fourfold.As these tests had been carried out in an artificial environment checks were carried out in the unidirectional-flow operating-room during total-hip arthroplasty. This was done by comparing conventional cotton gowns with non-woven gowns and total-body exhaust gowns. The results showed good correlation between the operating room and the chamber with the non-woven fabric gown but the total-body exhaust system did not perform as well in the operating room (12-fold compared to 66-fold) the difference being possibly due to the contribution from the patient. However, as this comparison was that which would be most open to influence from other variables confidence could be placed on the chamber test results.Values were also obtained for the total number of bacterial particles dispersed by persons during a standard exercise wearing different clothing.

SUMMARYOperation room clothing manufactured from disposable non-woven fabric (Barrier '450' fabric supplied by Johnson & Johnson Ltd) was assessed in a dispersal chamber and in plenum-ventilated operation rooms. It proved to be very comfortable to wear and was shown to be equally efective bacteriologically as the closely woven and uncomfortably hot Ventile material. As the majority of bacteria are known to be generated from below the waist, and hence not contained by an operation room gown, trousers were used as well as gowns. Dispersal chamber experiments suggested that when all staff wore non-woven trousers and the scrubbed sta8 wore gowns as well, a 55 per cent reduction would be achieved in the number of bacterial particles in the air of an operation room. In practice, 60 per cent reduction was achieved in one operation room and 43 per cent in another.The number of bacteria which could easily be removed from the surface of the gowns was surprisingly few. However, use of non-woven, as compared to cotton, clothing reduced these surface bacteria by 50-60 per cent. These bacleria would not be as easily dispersed into the air from the surface of non-woven gowns, as it was demonstrated that non-woven gowns, as well as gowns manufactured from certain artificial fibres, shed substantially fewer fibres.

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This study considers the upgrades that would be necessary to extend the life of the Transuranic Waste Storage and Assay Facility (TRUSAF) for an additional 30 years. The study also considers cleanup and conversion of the canyon area of the building for storage of solid waste. The 224-T Building was constructed in the 1940s to support process operations of the T-Plant. The function of the facility has changed over the years, and at present the northern half of the building is used to store solid waste. This portion of the building is referred to as the TRUSAF. TRUSAF is one of only two onsite facilities licensed to receive and store solid TRU wastes. Original intentions were for TRUSAF to be used for TRU solid waste storage until the WRAP 1 Facility became operational.