Information on the current Coronavirus outbreak is headline news at the moment, the Ministry of Health here in NZ is currently updating information as it comes to hand. This is an opportune time to reassess our information on face marks. As panic buying in china pushes people to great lengths of creativity to protect themselves, masks have also been flying off the shelves here but how effective are they?
Currently there is no medical advice that wearing masks outside a medical setting has any preventive benefit against the coronavirus. There maybe some benefit to wearing a mask if a person is sick, to help stop the spread from them, but benefits of a mask remain contentious.
When it comes to our clinical practice, are you using the correct level of face mask? AS/NZS 4381:2015 sets the current levels of single-use face masks which are measured on three performance criteria: Bacterial filtration (BFE), Fluid Resistance and breathability. There is also an additional measure for the maximum filtration mask N95, for particulates. The level of mask used is important in relation to the treatment provided and the level of protection our personal protective equipment (PPE) is required to give us. I believe a Level 2 single-use surgical mask is appropriate for general dentistry & Level 3 for aseptic procedures however, this should be assessed in individual clinics based on the treatment provided. An N95 may also be appropriate for air-abrasion due to the particulates produced. This covers the first step in mask selection. Eagle has a particularly easy to read article on this HERE. The level of mask protection should be found on the box, if not, ask you supplier.
We are required to change our face masks at the end of each patient treatment and not reuse them again on the same patient or additional patients.
A far cry from the early days of mask use when one mask would last us half a day.
This is because the single-use surgical mask degrades after approximately 20 minuets of use, due to condensation from our breath and possibly the environment we are working in. Thought the mask doesn't need to be changed every 20 minuets under normal circumstances it should always be immediately changed if it becomes damp as the effectiveness of the mask is no longer able to protect us.
Unfortunately, this also means that for those people who are trying to protect themselves by wearing masks all the time, it would provide very limited benefit and generally only offer a false sense of security. As for the extremely creative measures taken above, I guess the sense of some control can be found by doing something rather than nothing, but don't offer more than being amazed at human creativity.
This is also a good guide to mask selection by Crosstex which you might find helpful.