Firstly, you should ensure that the internal chamber is completely made of medical grade 316 stainless steel. This include the shelves, draws and runners. The leading laboratory incubator manufacturers will also usually paint the outside of the device in anti-microbial paint for increased contamination resistance.

You may want to opt for an incubator that has a fan-less heating system which will minimise the risk of internal contamination. In addition to this, it is always better to get an incubator with an inner glass door. This allows the user to view the samples without disturbing and potentially contaminating the internal atmosphere.

You should also make sure that the outer door has a very firm seal with no gaps present. The magnetic gasket around the door should be strong so that the seal is not compromised.