Sprinkler Head in Double Wall Stack

[KenRad]

I have an oven that will serve an automated powder coating process. I'm being asked by my insurance company to put sprinkler heads in the exhaust stacks (which I think is absurd). The stacks will be 18" diameter double wall (B-vent). Does anyone know of an access door designed for B-vent?

---KenRad

 

[johnp]

Hi KenRad,

Insurance is a business. Sometimes the inspectors know what's in the book, but they don't know for sure why, or if it relates to reality. So they say - just to make sure, let's make them comply with the letter of the book. It's traditional you know.

I worked as a mechanical engineer in the mineral processing industry. The process involves heating our mineral in a reduction kiln to 1200.C using coal. The product comes out the end with inclusions of ash, soot, sinter and carbon.

Is the dust explosive? Can we weld without being blow to high heaven? Ask the Supervisors. The Safety Officer doesn't think so - why it's just been through the fire. An experienced Supervisor says "We've been working with the stuff for 20 years. It has never caught fire yet, let alone explode". What do the specifications say? Nothing. Design parameters? Nothing.

Old engineer "I seem to remember the Consultants may have done some tests 20 years ago, but there is are no records any more of that."

So I ask the Fire Department. The Fire Department refer me to the Mines Department. The Mines Department refer me to the Insurers. The Insurers say it's a Management Safety Issue - you have to ask your Managers. The Managers say - ask the Operators. The Operators are the ones asking the Questions. No one really knows.

Come on, let's be real. Can't we test the stuff in a bomb calorimeter, or something? The Laboratories will do it for a $1,000 or so. Yes, but it can get complicated. It depends on the concentration - the air to dust ratio. But no one cares, or wants to raise an account to pay for the test. Why do you need it?

So, just to comply with the Insurer's book of words our baghouses should be fitted with sprinkler pipes at an additional cost of $5,000. But no one will spend the money, because they know it's bullshit in the first place. So we stall, and bluff. And the fire risk remains undefines, obscure, but we don't think it's real.

Should we do a HAZOP? That's the wrong vehicle. The Safety Mangers insists we should do a HAZAN. What's that? Google - it's the name of an Arab singer. No such acronym, or analysis procedure. Do you mean HAZID?

Regards - Sgt John Rozentals
University Regiment (retired)

http://www.latviantourists.com.au

Johnp.Rz

http://www.mets.net.au

 

[AbbyNormal]

flue, pretty hot, acidic, a sprinkler head to go off at 800F?

How about trying to appease the insurance company with an A-vent, or even the superinsulated chimneys for solid fuels.

Take the "V" out of HVAC and you are left with a HAC(k) job.

 

[stookeyfpe]

How about the fact that it is not required by NFPA 80, standard for industrial ovens? Also, putting sprinklers inside of an industrial oven needs to be well thought out. Accidental sprinkler operation can possible produce a deflagration due to the rapid generation of steam.