COVID-19 Printable PAPR (Powered Air Purifying Respirator)  

RE: COVID-19 Printable PAPR (Powered Air Purifying Respirator)

How does it's puncture and tear resistance compare to the previous bag you were using?

RE: COVID-19 Printable PAPR (Powered Air Purifying Respirator)

It's a stiffer plastic and thus more prone to fracture failure, but I'm fairly impressed by how well it holds up despite aggressive wadding and folding. It's tougher than I expected. For clinical use it's durable enough to last the day. I'm definitely not in fear of it rupturing while I'm wearing it. With a puncture, you can create a propagable fracture as opposed to polyethylene.

RE: COVID-19 Printable PAPR (Powered Air Purifying Respirator)

I should clarify, a small need puncture won't start a fracture, but a larger hole like a knife blade will start a fracturable defect.

RE: COVID-19 Printable PAPR (Powered Air Purifying Respirator)

As long as your 'tester' is happy with it. 😀 As for knife puncture...If someone punctures it with a knife, a fracture is the least of your worries. 😀 

RE: COVID-19 Printable PAPR (Powered Air Purifying Respirator)

One of my partners (years ago) got all the way into the operating room with a patient and it was time to put the patient to sleep. 

Patient pull out a gun and asks my partner to hold onto it for him.

We don't allow weapons on campus, but sometimes they do get in.

I myself have only needed once for the police escort someone brandishing a knife out of my surgery center.

Nope, we don't bother with hospital security for that. Metro police is your friend.

Deleting Fan Director

Got objective airflow measurements and found the optional fan director, while seeming to improve the subjective wear experience, impacts total airflow by about 20%. I have deleted that optional STL from the project.

RE: COVID-19 Printable PAPR (Powered Air Purifying Respirator)

Having read the fascinating discussion above, I was wondering if anyone might be interested in helping my colleague with a suggested prototype for a personal protective mask. The attached sketch illustrates a framework over which a paper kitchen wipe can be placed and trimmed to size including the hole for the valve unit. I know nothing about 3d printing but, Mike, as an engineer, assumes that the two components could be manufactured in flat form or possibly in operational form. Mike also has an idea for a positive pressure mask using a small motor and outlet valve. If there is any interest out there please contact Mike at [email protected]

RE: COVID-19 Printable PAPR (Powered Air Purifying Respirator)

I will have you start a new topic for that mask instead of piggybacking on the Bunny PAPR. 

Masks are a lower grade form of protection, this thread discusses the more protective PAPR..

RE: COVID-19 Printable PAPR (Powered Air Purifying Respirator)

Apologies @guy-k2

As a newcomer to the forum, I was simply trying to locate an appropriate mechanism to share Mike's idea with those who have an interest in the protection-wear opportunities of 3D printing.

I wasn't sure how to start a new topic. No piggybacking intended, as your design is clearly for a totally different market opportunity.

Best wishes for reaching a large market.

RE: COVID-19 Printable PAPR (Powered Air Purifying Respirator)

Upper right, above topic list, there should be an "add topic" button

RE: COVID-19 Printable PAPR (Powered Air Purifying Respirator)

TIP for fitting clearbags bag onto Bunny PAPR. If wearer has a large head, the smaller, clearbags OPP bag needs to have its seam in FRONT of the filter penetration. That leaves more room in front for airflow from fan to front and down face. If penetration is in front of seam, large headed wearer may not have enough room in front of forehead to bag. Aim for at least 3 cm space between bag and forehead. Had a lot of trouble getting a large male comfortable until we moved the filter penetration to about 4 cm behind seam. Also, use of the new elliptical based flutter valves allowed better total airflow compared to the old deflector requring ones.

RE: COVID-19 Printable PAPR (Powered Air Purifying Respirator)

New video regarding flutter valve function and creation

RE: COVID-19 Printable PAPR (Powered Air Purifying Respirator)

Update with info about elliptical flutter valve fittings, clearbags, and pivoting fan mount.

RE: COVID-19 Printable PAPR (Powered Air Purifying Respirator)

hopefully covid-19 ends quickly

RE: COVID-19 Printable PAPR (Powered Air Purifying Respirator)

Video about selecting anesthesia viral filters for your Bunny PAPR

RE: COVID-19 Printable PAPR (Powered Air Purifying Respirator)

Brief Assembly for Wear Guide

RE: COVID-19 Printable PAPR (Powered Air Purifying Respirator)

You have covered all bases admirably, however with regard to wearing a mask under the hood to protect others around you from your exhalations, would it be possible to pass the exhaust air through a viral protection filter as with the input. Also, could you not make a big saving on gloves if you cleaned them with hand wash whilst still wearing them rather than replacing them for every step of the cycle?

RE: COVID-19 Printable PAPR (Powered Air Purifying Respirator)

Yes, I mention using viral filters as outputs as an option and have worn the PAPR in that configuration early on. However, that configuration uses 3 filters instead of just one. That's a little hard to justify during shortages.

Washing gloves rather than replacing them might be accepted in extreme conditions, but they are pretty fragile and likely to break during extended use. Hosptial infection control department would have a cow, if anyone in the US did that.

Twin filter fan flange

Added twin filter fan flange back into models. Allows running of two high resistance HMEF's in parallel to achieve adequate airflow. Some HMEF's have a too high flow resistance to work well in BunnyPAPR. Twin flange is not intended as a standard part, but only for facilities unable to obtain lower air resistance viral filters.

Stethoscope

I was asked about using a stethoscope with the BunnyPAPR. You cannot put one on over the bag, but you can use a stethoscope by putting it on before the PAPR. Works better with slimmer, long scopes. Put scope on ears and swing it forward of your chin BEFORE putting on PAPR and strap. Then you can reach through bag to put earpieces in/out of ears. It's not ideal, but if you really must use a stethoscope, there is a way.

This pict illustrates the positioning. I am wearing the Halyard strap but omitted the bag to better show the scope.