Had no idea. Grinding milling sawing etc of plastic wood and other organic based materials and of metals lead to dust. Ok nothing new there. These dust particles accumulate on the floor. Ok. Nothing new.
In presence of a spark these particles can ignite and create explosion. Leads to some particles airborne. Another spark and all hell breaks loose.
Enough to bring down buildings. Jesus Christ. Did I say had no idea?
Source last week WSJ
Re: Dust and Fire
Very nice find OP. On Mon Aug 4 WSJ, the title of an article on By "Dust is the likely cause of Chinese factory blast". 71 workers killed in an auto parts factory with high dust levels. This was at a polishing workshop. The workshop issued mouth muffler" "to fend against dust" said an employee.
"Combustible dust is a widely known industrial hazard" with deaths in factories worldwide.
Apparently the dust was everywhere from floor to air.
Re: Dust and Fire
One more view for Nelson please. Reply prior to this with views make it all 1's. Would that be 1+Nelson?
Re: Dust and Fire
[QUOTE]
"Combustible dust is a widely known industrial hazard" with deaths in factories worldwide
[/QUOTE]
What preventive measures should be taken to combat this problem ?
Re: Dust and Fire
I am not an expert. But OSHA for example has air quality standards. The factory floor shoukd be kept free of dust. That would mean assigning cleaning staff. As of now, the factory doesn't care to keep the work environment dust free.
Apparently the masks get laden with thick layers of dust within 3 hours.
On a side note, the two contributors here is
LP
OP
Where are
MP
NP
Re: Dust and Fire
Only flammable material will catch fire, suspended particles in air caused by sawing, grinding of wood and other inflammable material are a threat. A small spark (even invisible to naked eye) caused by connecting/disconnecting electrical appliances can ignite these suspended particles resulting in ‘air/atmosphere’ catching fire which is same as a huge explosion. This fire spreads fastest and can not be put out by conventional methods.
Places where such particles are expected are classified into zones. These areas are usually called hazardous zones, although presence of inflammable gas can also result in such fires. Zone classification details can be found below
Classification in Zones
For such areas strict regulations exist which prevent accidental sparks. Electrical enclosures designed for these are called explosion proof cabinets.
In 2009, the towel factory fire incident in Karachi was precisely due to this phenomena, the suspended towel particles are extremely inflammable and a small spark due to negligence and lack of safety precautions caused such widespread damage and loss of numerous lives.
Re: Dust and Fire
Thank you, crabman. Very informative. Welcome to the Science section of this forum.
Re: Dust and Fire
I am intrigued. Can anyone explain or share a link explaining how suspended particles catch on fire?
thanks!
Re: Dust and Fire
A simple way to understand would be comparing this dust with methane gas burning in our stoves, the gas particles are infinitesimally small, and they do diffuse in the whole house if the stove is kept on without lighting it up. These particles are fuel, and likewise saw dust and fabric particles which are inherently organic are fuel for fire, except that these are a lot bigger than gas particles. Besides being a fire hazard they are also hazardous if inhaled without masks, they cause congestion of lungs and irritation in nose. Most of the facilities where such environment exists require workers to wear dust masks.
For further understanding try going through the link below
http://www.hse.gov.uk/fireandexplosion/zoning.pdf