[nudephil (OP)]

Here's a question from David:

If was to increase the ACH (air change per hour) in a dental surgery, could I see a patient faster due to AGPs (air generated particles) present after surgery? Public Health England doesn’t comment on this anywhere in their 67-page document.

Any thoughts?

[alancalverd]

Don't expect PHE to commit to anything these days. They are in the eye of a political storm and unlikely to issue anything but platitudes during their redisorganisation.

If you have total loss or an efficient and well maintained  HEPA-filtered recirculatory system, increasing ACH should indeed reduce the concentration of AGPs more quickly. You will however need to demonstrate enhanced sterility if you depart from whatever is the current consensus patient flow.

There is a lot of interest in ceiling-level, ultraviolet-sterilised  laminar airflow  for surgeries and several devices are available in the UK, but from my observations both as a patient and as an x-ray safety advisor to many dentists, the ratelimiting factor at present seems to be surface decontamination and donning the biological isolation kit for AGP procedures.

If David wants to drop me a PM I have some ideas for developing a dentist-specific product to improve AGP safety with potentially infectious patients, and would appreciate a willing clinical partner! 

[Petrochemicals]

Yes you can, inline with government regulations concerning healthcare facilities, but your system may need some modification.

Positive pressure is the best way to go, clean pure air pumped in and then stale air withdrawn. If you decide to ramp it up, go for a heat exchange unit. You will also need to control the airflow, negative pressure ceiling including the corners, positive fresh inlet air at the base of the room. There are also regulations about jettisoning potentially hazardous air into the environment.