Grounding my Dust Collection System

[Forrest Anderson]

There has never been a documented case of a wood dust explosion (fire yes, explosion no). 

The following two two wood-dust explosions, which are documented by the US Government's OSHA (Occupational Safety & Health Administration) database, seem to fit the bill of "explosion but no fire":

---------------------http://www.osha.gov/pls/imis/accidentsearch.accident_detail?id=201031796
Craftsman Millworks Inc.
At approximately 9:40 p.m. on August 10, 1998, Employee #1, a supervisor and operator in the sanding department, observed excessive sawdust coming out of one of the sanders, indicating a problem in the dust collection system. After checking the sanding unit, Employee #1 went to inspect the baghouse dust collection system outside the main mill, on the east side of the facility. Employee #1 was standing on the top step of a wooden stepladder to access the 6 ft 3 in. high top of the dust collector frame. He was about to shake the air relief bags when there was an explosion in the cyclone-baghouse dust collection system. Employee #1 was thrown back from the top of the baghouse frame and struck a pallet of cardboard boxes before falling to the ground. He sustained a concussion and a sprained right knee, and was transported to Lakewood Regional Hospital in Lakewood, CA.
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---------------------http://www.osha.gov/pls/imis/accidentsearch.accident_detail?id=170724678
Louisiana-Pacific Corp
On April 11, 1998, Employee #1, a sander operator for a fiberboard manufacturer, was working in the fiberboard area when the sander dust exploded. He suffered third-degree burns to his hands, and second-degree burns on his face.
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Forrest

 

[Dave Ronyak]

Those interested in the risks of wood dust might also visit Oneida's site.  I imagine they know a thing or two about dust collection systems and attendant hazards.

Dave R.

 

[Bru]

Thanks everyone for your response. I finished my dust collection last night, turned on my jointer and with in 30 seconds touched my cyclone (homemade out of a metal trash can) and was given a nice static shock. I (being the fool that I am had to shock myself about 8-9 times) then hooked up the ground and the shocking stopped. Thanks to all for the help. My time spent hooking up the ground was maybe 10 minutes. Cost CHEAP! Thanks again. Bru ;D Nice not to have to worry! Or get shocked, or worst....

 

[Greg_R]

My apologies for semi-derailing this thread in an attempt to educate myself in my 2nd post.  Bru, I agree that grounding the system is fast and cheap, especially with the metallic duct tape.  Glad to hear that everything worked out.

No, there is nothing in this MSDS that states anything regarding static discharge.

I had a lengthy post pointing out section #5 and section #10 but decided it just wasn't worth discussing minutiae on a message board (especially since you think it's an argument).  Re-reading my 1st post I can see that it was misleading and spoke in broad generalities instead of focusing on the question at hand (static).  My apologies...

 

[Scott W.]

Thanks everyone for your response. I finished my dust collection last night, turned on my jointer and with in 30 seconds touched my cyclone (homemade out of a metal trash can) and was given a nice static shock. I (being the fool that I am had to shock myself about 8-9 times) then hooked up the ground and the shocking stopped. Thanks to all for the help. My time spent hooking up the ground was maybe 10 minutes. Cost CHEAP! Thanks again. Bru ;D Nice not to have to worry! Or get shocked, or worst....

Glad to hear it all worked out Bru 

Scott W.

 

[Steve Jones]

Gosh, I'm really, really delighted to see that the argument about which authority claims wood dust is explosive or not is ongoing.

It's so informative and entertaining, I thought i was following this forum to gain insight into how others are usefully employing their Festool products and maybe to learn something new myself or pass on something I found to someone else.

Instead we are all eager to hear the next exciting installment, who will win the argument?

I'm on the edge on my seat.

 

[Dave Ronyak]

Rather than an argument, how about some self-test demonstrations?  A variation of one of Mr. Wizard's science demonstrations (some of you must be old enough to know who I am writing about) should do.  Starting with an empty cylindrical cardboard oatmeal container, make a hole near the bottom of the cylinder and install a small piece of rubber or plastic hose through that hole.  Place a little of your test dust in the bottom.  A couple of tablespoons should do.  Then place a small lighted candle in its candlestick holder into the container.  Put on the cardboard lid.  Then blow into the tube.  If your dust is capable of causing an explosion, you should get a small one.  Obviously, you should do this somewhere outside, and make certain you have at least 10 ft of hose and something to shield yourself.  If nothing happens with your wood dust, to prove to yourself that dust explosions can and do happen, try it with common finely ground wheat flour.  With the flour, you should get one of the low speed whaa-rump explosions, not a sharp pop or crack like you hear from a rifle.

Are any of you photo (preferably video) saavy people going to give all of us a true safety demonstration to view on FOG?

Dave R.

 

[Bru]

Dave I'm glad you added the 10' hose to protect yourself part. I'd hate to see video of someone toasting their face.....Bru
I still don't understand an argument about shop safety. If mines overkill, it's my choice. Thanks again for all the help, at least I feel safer.