Petri dishes are typically made from glass or plastic. They are widely used in microbiology labs to make up agar and media plates for bacterial cell and fungal cultures. We often get asked what is the difference between a single vented and triple vented petri dish and which is best for a certain application. So we have put together this terminology quick guide to help explain the differences.
Vented petri dishes feature one or more small plastic protrusions on the inside of the lid so that it does not sit completely flat to the base. Therefore allowing gaseous exchange.
- Triple vented- this design lifts the lid off the petri dish base all the way round and aids air flow and gaseous exchange. It is ideal for aerobic cultures and for short term work due to the increase in moisture evaporation.
- Single vented- this design lifts the lid from the base in one point and allows for a limited air flow which helps to minimise evaporation. It is great for longer term aerobic work.
- Non-vented- this design does not have any vents and the lid will sit flat on the base. It is suitable for anaerobic work. When you have poured your plate, the lack of air flow could lead to a lot of condensation on the lid. They will also take longer to set due to the restriction on air flow in the plate.
- Aseptic- manufactured in clean room conditions to exclude microbiological contamination, although the plate itself has not been subjected to an active process to destroy it, as with sterile plates. Aseptic plates are sufficiently free to contaminants for the majority of applications.
- Sterile- Sterilised (usually by gamma irradiation) to ensure all microbiological contamination has been destroyed