Dry heat sterilizer for animal bedding and cages

Technical requirements

A dry heat sterilizer is required for the routine sterilization of assembled animal cages, bedding and other thermostable items involved in laboratory animal science.

General characteristics:

-Electrically powered heating, either 240V (2-phase) or 400V (3-phase)

-Operating temperature of 140 deg C for routine use, no higher than 210°C at any time

-Air circulation required to ensure even temperature distribution throughout static holding period

-Intake air must be filtered to <0.3um (micro-metre)

-Exhaust air must be filtered to <0.3um (micro-metre)

-Throughput must be able to exceed 3320 cages per working week

-There are no weight constraints

Dimensions:

Internal chamber dimensions should not be LESS than

-Width 1000mm

-Depth 2300mm

-Height 2130mm

Must be able to accommodate logistics trolleys and plenum racks for (e.g.) GM500 mouse IVC cages (Tecniplast) and must be able to process 3320 assembled mouse cages in a standard working week (5 days, 8 hours per day). You may include scheduled start and unattended cycle end times.

External device dimensions should NOT EXCEED

-Width 3600mm

-Depth 3150mm

-Height 2750mm

Design considerations

The sterilizer may be pit mounted. The door openings should be at opposite sides of the sterilizer so that un-sterile cargo is loaded from the external side, and sterile cargo is unloaded from the internal side (pass-through design). Human Machine Interface (“HMI”) (i.e. control panel) controls should be located on the external side, with the ability to control cycle operation and safely open doors from the internal side as well. There needs to be the capacity to save at least 10 configured control settings for different load types.

Doors should have an airtight seal, preferably an inflatable gasket-type. Both doors must interlock when the machine is operating. When a cycle fail occurs, or an emergency stop is used, only the door on the side that initiated that cycle should be unlocked until the control system is reset. The existing stainless steel facia [surrounding an obsolete sterilizer] needs to be reinstated to seal with all existing finished surfaces to re-create an airtight barrier between clean and dirty access doors.

The floor of the cargo chamber must be flush or near flush with the finished floor level on both sides of the sterilizer. This is so heavy loads can be easily wheeled in and out. The maximum threshold at each door is 15mm and the threshold must be bevelled for smooth transit.

Extracted air must be mechanically exhausted via ducting to the outside to minimise cycle time.

Each operation must be recorded on paper at the Human-Machine Interface (control panel), and must also have the capacity to save electronic run data in an accessible format . Alarm history must also be stored.

The steriliser must have overtemperature sensors and control systems independent of the main controls in case of sensor failure in the main circuit. An audible alarm must sound in cases of overtemperature and failed airflow.

Full validation of various load types must be achievable at our location. Access for installation is good, with double doorway and no steps.

The sterilizer must be CE certified. You must also be able to provide customer references for a closely matched sterilizer and provide reliability information for equivalent machines in similar environments for a reasonable period of time to give high degree confidence.