SYS AIR Next to the Workpiece?

[onocoffee]

I've been planning to build one of those Corsi-Rosenthal type dust filtration units with five Merv 13 filters. My intention has been to fly it overhead. At the moment, I've been using a 20" box fan with a 4" thick Merv 11 filter as an interim measure.

I think it was on the last Festool Live, Sedge was demonstrating the SYS-AIR and had it setup on the bench next to the workpiece he was sanding - and you could see the SYS-AIR suctioning the remnant dust directly into the unit.

In the Fine Woodworking Podcast back in October, Dr. Seri Robinson noted that dust in a woodshop can remain airborne for three days. I've been wondering about the effectiveness of a overhead dust filter. Now that I'm older, I've been quite concerned about getting dust particulates in my lungs, which has been the driving force of me investing into Festool.

I'm interested to hear your thoughts on this. Are overhead filters effective? Should the filter be next to the workpiece? Interested to learn of your experiences. Thanks!

 

[usernumber1]

My 4 sided filter box is above the work table and I have less pm2.5 in the shop than when the oven in the house is roasting potatoes
For extreme situations I blow a fan out the door (in our out depending how much space I have)

In my view festool provides portability and a professional looking unit that is ready out of the box. Although I'm not sure it's certified, and I wonder how many customers get the non HEPA

Also, I am not certain it can filter fast enough at 400CFM . they estimate 3 ACH for a 600sqft.
I don't think that's enough, I would prefer 6 minimum. to get 6 ACH for a room 600 sq ft×10 ft ceiling math says you need 600 CFM.

if you are serious about this, I would suggest having a way to measure particles that you are concerned with. Anything else is just guesswork

 

[Cheese]

If you are serious about this, I would suggest having a way to measure particles that you are concerned with. Anything else is just guesswork

+1

Sedge noted that a particle 1.0 µm in size needs 7 hours to drop 3 ft.

So, if you're working on something at the 3 foot level, to what height do those particles travel before they start their descent?

It would seem that having the SYS-AIR at working height or slightly above working height would be the best situation. Suspending the SYS-AIR from the ceiling would be the 2nd best alternative while having the SYS-AIR at floor level would provide the least amount of air scrubbing. 

A particle counter would quickly validate if my assumptions are correct or not.

 

[woodbutcherbower]

Dr. Seri Robinson noted that dust in a woodshop can remain airborne for three days.

Just my opinion - but that's quite the generalisation and is totally meaningless. How big's the shop? Single-car garage size? IKEA store size? What's the dust volume? A guy with a sander for 10 minutes? A full-scale production shop? How big are the particles? Drywall size? Sander size? Saw size? What about ventilation? Are the windows open? There are too many variables to give a statement like that any credence IMO.

 

[Coen]

What happens after three days?

 

[BJM9818]

I have the HEPA one sitting at my Sherwin Williams store picking it up tomorrow.  I have a large HEPA air filter I bring on larger jobs when I’m setting up a zip wall containment but it’s a PITA for a small job.  Excited to try this out since it fits into a Systainer footprint.