CAGE PROCESSING in Animal Facilities - GV-SOLAS

PVP:FVP:VWD:prevacuum processfractionated vacuum process (pulsing)vacuum with drying timeVWOD: vacuum without drying timeICBP:PRAP:indirect cooling with back pressure(slow) pressure relief to atmospheric pressurePlease pay attention to the following aspects:• When sterilising material made of polycarbonate, alkaline residues on the items need to be avoided (otherwisethe material, due to hydrolysis, will be destroyed; please refer to chapter 9.1).• When sterilising feed or bedding in bags, needled plastic bags or a steam permeable bag material shouldbe used.• With liquid products: Temperature measurement in a reference vessel should be performed (otherwisedanger to life due to delayed boiling; removal temperature < 80 °C); active cooling with back pressure ispreferred.• When sterilising filled polycarbonate water bottles, a low steam sterilisation temperature, e.g. 118 °C, isrecommended in order to protect the material, with a longer dwell time, e.g. 40 min, if necessary. In casemicrobiological testing is wanted, inactivation of the microbes requires a much longer exposure time.• When sterilising water bottles with caps on, bottles with a silicone sealing ring are mandatory in order toavoid leakage (different expansion coefficients of metal and plastic).• Solids (and cage bases in particular) and porous loads (cage bases with bedding) should be as dry as possiblewhen put into a steriliser (evaporative heat loss, drying time).• Waste treatment: Chamber exhaust air and condensate are to be treated (e.g. exhaust air filtration andcondensate steam sterilisation). It is important to use packaging to ensure steam access to all waste.• When sterilising carcasses, special programs are to be used, depending on the size of the animal. Pleaseconsult the machine manufacturer.• When loading porous material (bedding, feed) hygroscopic condensation can cause local overheating.4.5.1.3 DimensionsSterilisers can have different characteristics of design:• chamber with floor level access / without floor level access• one-door / two-doorThe work space is usually indicated in decimetre measuring height x width x depth. Hence, a steriliser measuring18x12x15 possesses a usable rectangular volume of at least 1800 mm (h) x 1200 mm (w) x 1500 mm(d). The actual internal chamber size is larger in all dimensions and should be adapted to the loading systemaccordingly.The sizes usually preferred for sterilisers with floor level access in animal facilities are:18x10x1518x12x15Depending on the structural conditions of the building, external dimensions of some machine parts must beadapted for the transport (into the building) and installation situation (please refer to chapter 5).4.5.1.4 Technical componentsA detailed description of the general requirements of machine and safety engineering is provided in DIN58951-2. Please refer to below some important examples.Airtight sealing of barrier areasA general description of the sealing design is provided in DIN 58951-2, Art. 6.7. In practice, the sealing shouldbe mechanically fixed to the steam sterilisation chamber and be equally well connected to the side walls andfloor. Especially with machines designed in a pit, it is important to seal the floor area beneath the chamber, asthis area will not be accessible afterwards. The maximum permitted leakage equates to the requirements of airconditioning units in order to maintain defined pressure differences in the separate areas.30Cage Processing in Animal Facilities · 4th issue · 2013