Put air filters on FFM, for COVID-19 protection

[Javik]

Due to COVID-19 it seems I should probably wear my Ocean Reef Neptune full face mask in public without the tank.

It would be a heck of a lot more comfortable than a surgical mask or other simple cloth mask. The one-way airflow will keep the inside of the mask cool and free of moisture.

However I need some way to cover both the inlet and outlet ports with a fabric filter, to protect both me and others from airborne droplets.

I am thinking some sort of thick padded sewn elastic fabric wrap could be placed around the "nose" of the mask so that it covers both the air inlet and exhaust ports.

The communication port can be capped as it works fine to talk in the mask on the surface, and a rubber cap put on the hose connector to keep out contaminants.

It may also work to adapt N95 and better respirator filters directly onto the Ocean Reef air ports.

Has anyone else thought about ways to do this?

 

[Umuntu]

Due to COVID-19 it seems I should probably wear my Ocean Reef Neptune full face mask in public without the tank.

It would be a heck of a lot more comfortable than a surgical mask or other simple cloth mask. The one-way airflow will keep the inside of the mask cool and free of moisture.

However I need some way to cover both the inlet and outlet ports with a fabric filter, to protect both me and others from airborne droplets.

I am thinking some sort of thick padded sewn elastic fabric wrap could be placed around the "nose" of the mask so that it covers both the air inlet and exhaust ports.

The communication port can be capped as it works fine to talk in the mask on the surface, and a rubber cap put on the hose connector to keep out contaminants.

It may also work to adapt N95 and better respirator filters directly onto the Ocean Reef air ports.

Has anyone else thought about ways to do this?

COVID-19 | OCEAN REEF Group

 

[Addicted2H2O]

COVID-19 | OCEAN REEF Group

That article only shows what Ocean Reef has come up with for SNORKEL masks. Not full face scuba masks.

OP, I think it would be easier to use a fabric filter and put it inside the SAV and then inside the exhaust port rather than try to "cover" the oranasal pocket. I've considered this myself but haven't yet taken it from concept to practice. I'm sure I'd get a few looks out in public if I did, though.

 

[Javik]

The method Ocean Reef is showing on their website is an incomplete solution because it does not have any sort of moisture trap over the exhaust port. So the health worker is protected from the patient, but if the health worker themselves has the virus, they will cough a fine mist of mucous droplets straight out the exhaust port. There needs to be a filter / moisture trap on both the inlet and outlet.

Also I am somewhat annoyed to see they filed for a patent on their filter adapter. Yep lets cash in on the emergency situation, rather than making the elastomer adapter freely available to the world as a 3D model to use during the crisis. That is not the goal for what I am trying to do.

 

[Javik]

Also on a side note, it seems feasible to use SCUBA tanks and full face masks in a health setting directly the way they are designed to work underwater. For myself as a 5' 11" adult, I find that I use about 0.7 cfm when swimming relaxed. 60 minutes * 0.7 = 42 cu/ft.

So a smallish and lightweight bottle would work fine for surface air breathing from a SCUBA tank and FFM in a hospital setting. It provides full protection from patients coughing or sneezing on you.

Probably would want to get a firefighting or mine safety style tank backpack harness to eliminate the bulk of the unnecessary BC.

The downside.... the hospital needs to invest in a tank filling station, and needs to keep a constant rotation of charged cylinders on hand.

 

[Javik]

Okay so, if you have the Ocean Reef G.Diver or similar FFM equipped with the surface air breathing port, there is a way to attach filters to the inlet and exhaust ports. This can be done with either a single molded silicone rubber attachment, or with two separate ones.

Generally, you remove the soft flexible elastomer rings on the inlet and exhaust port, and then slide elastic silicone rubber adapters onto the ports in the same place where those rings were.

Surface air inlet:

Soft ring has internal notches so it does not spin on the valve body.

Exhaust port:

This ring is decorative and does nothing but look pretty.

They are interchangeable:

Comparing the inlet and exhaust ports:

FFM reassembled, with the soft elastomer rings removed:

 

[Javik]

Making a silicone adapter for the exhaust port is no biggie, just make a lipped flange that fits around the exhaust port.

For the inlet port, it is a bit more challenging because the normal air inlet is around the side of the valve, not the end/top.. Solution, one of either:

1. Modify the twist knob to have circular notches around the edge about 5 mm deep so that air can enter from the top of the knob. This is feasible because the actual sealing O-ring is recessed, looks like about 8 - 10mm deep under the surface air twist valve.

2. Make a silicone adapter which has a ribbed ring of notches around the inside of the lipped flange so air can pass around the sides of the surface air knob, and enter through the side gap as usual. This would not require modifying the surface air knob.