MCEM is located on the Clayton Campus at 10 Innovation Walk, in a purpose-built, high stability building which was completed in late 2007. This building provides a world class, ultrastable environment to optimise instrument performance, as well as providing a supportive and user-friendly environment for researchers.
The mechanical, electromagnetic, thermal and acoustic stability specifications for ultrahigh resolution microscopes are exceptionally demanding. The new MCEM building is one of the most stable such buildings worldwide.
The design process included extensive liaison with major international facilities on their building design and MCEM is particularly grateful for advice from the Triebenberg Laboratory (as well as, Oxford University, the Canadian National Centre for Electron Microscopy, the US National Centre for Electron Microscopy and the FEI Nanoport).
The MCEM building has received a number of awards:
"Engineering Excellence Award for Infrastructure (projects up to and including $20 million)" by Engineers' Australia - Victoria Division;
|"Public Architecture Award" by the Australian Institute of Architects - Victoria;|
|"Public Architecture Award" by the Australian Institute of Architects 2009 National Architecture Award; and|
|"Excellence in Acoustics Award 2008" by the Australian Acoustical Society.|
Outline of Design Concepts
An outline of the basic design concepts are summarised below. The specifications for the Grade A labs, in each area, are given in brackets.
For stability, the air-conditioning, water cooling and electrical plant are all located in a separate plant building about 10 metres to the east of the main building.
(<0.5microg <10Hz, <5microg >10Hz)
Each microscope lab is effectively a separate small building within the main building. The grade A and B labs have a thick (1m and 0.6m) concrete slab floor that is mechanically isolated from the surrounding block work walls that, in turn, are on separate footings and so are isolated from the rest of the building. The lab roofs sit on the block work walls and are independent of the main building roof which is itself supported separately. The only source of mechanical disturbance that cannot be mitigated by this design are low frequency vertical vibrations, the source of which can be kilometres away.
To minimise mechanical disturbance from air-conditioning airflows, room temperature is controlled using water-cooled radiative panels on the ceiling, rather than high throughput air exchange.
Airlocks have been used to minimise pressure gradients when doors into the lab are opened, and for acoustic isolation.
(<0.1°C/30min and <0.005°C/sec)
To achieve thermal stability within the lab, any heat sources that can be separated from the main instrument, such a power supplies, water chillers and rotary pumps, are placed in adjacent utility rooms.
Airlocks have been used to minimise temperature fluctuations when doors into the lab are opened.
High ceiling, large volume rooms provide a large thermal mass.
Low flow supply air from three outlets, combined with variable cooling panel temperatures, give sufficient adjustable parameters to achieve the specified stability.
Background EMF - (<0.05mG peak to peak, all frequencies)
The building is positioned sufficiently far from lifts to ensure the EMF they generate is under 0.05mG.
The only other source of quasi-DC EMF is the traffic on the University’s inner western ring road. The section of this road in the vicinity of the building has been pedestrianised to eliminate this problem.
Unfortunately, Australian earthing regulations require that individual buildings are separately earthed, resulting in potential differences between adjacent buildings and hence currents flowing in the earth. These generate an all pervasive and substantial background source of EMF (~1mG) throughout every Australian city. Earth currents have proved to be a problem at Monash, in particular due to its highly conducting clay soil. To mitigate this, extensive work has been undertaken within 200 metres of the MCEM building site, to minimise earth currents, including the re-wiring of 6 substations, removing several hundred amperes of current flowing into the earth!
One of the grade A laboratories is shielded with carbon steel.
Minimising EMF generated by the building itself
- Where possible, the building has been constructed from non-conducting materials (glass walls, wooden frame and roof) to minimise the risk of EMF generated by conducting loops within the building.
- Shielded, twisted pair cables are used throughout to minimise EMF generated by power services within the building.
- Wiring to earth is in a star configuration to minimise risk of ground loops.
- The path of cables into the building is designed to maximise the distance of cable bundles from the main instrument labs and minimise the number of cables into the labs.
- Low EMF lighting is used. Chairs made from non magnetic materials are used in front of instrument columns.
- The main switchboard and UPSs are located in the separate plant building several metres from the main building.
- Any structural steel is earthed to a common point.
- Items such as airconditioning duct work have non-conducting spacers at frequent intervals.