Getting to Know Dust Explosions in Five Minutes

Getting to Know Dust Explosions in Five Minutes
Photo Credit: bobostudio @Flickr CC BY 2.0
What you need to know

Why does dust explode or burn?

Listen
powered by Cyberon

The Formosa Fun Coast water park in New Taipei City burst into flames on the night of June 27 after colored powder was shot from the stage. Hundreds of tourists were burned and the Taiwanese have come to realize the danger of dust.

The five main causes of dust explosion are: large amounts of flammable dust disseminated in the air, source of ignition, poor ventilation, sufficient oxygen and careless use of powder.

Health Business Weekly reports, many people believe the cause of this tragedy is lack of professional knowledge and negligence of the danger of dust. The reason behind the water park incident is still under investigation.

Why does dust explode or burn? Here are four conditions according to Wikipedia:

1. A combustible dust
2. The dust is suspended in the air at a sufficiently high concentration
3. There is an oxidant (typically atmospheric oxygen)
4. There is an ignition source

A Taiwanese Facebook page shows the following Wikipedia facts through five pictures.

Dust explosions are caused by flammable particles burning rapidly in a closed space. If an indoor environment has sufficient oxygen where the dust is at a high concentration and meets a heat source, then there might be a chance of explosion.

A vacuumed space is created after an explosion, and more dust clusters towards the center, which causes a second and more violent explosion.

Explosions produce poison gases such as carbon monoxide or the gases powder decomposes into. Many ordinary matters, such as grains, flour, sugar, powdered milk and pollen, can form dangerous gas dust clouds. Powdered metals, like aluminum and titanium, combined with the air can become explosive airborne dust.

The main ignition sources are: electro static discharge, friction, equipment that produces electric arcs, high-temperature surfaces and flames. Controlling the density of powder, increasing ventilation and managing sources of fire can prevent dust explosions.

CommonWealth reports, dust explosion prevention is a highly technical job. Flour mills and animal feed factories are also prone to dust explosions, and therefore emphasize on mandatory training at the labor affairs bureau. The 1991 flour mill explosion in Wuri, Taichung led to 20 injured.

Photo Credit: 作者名稱 @Flickr CC BY SA 2.0

Photo Credit: 作者名稱 @Flickr CC BY SA 2.0

Aside from the party at the water park, the color run fad in the past few years also sprays colored powder, and has been criticized for pollution and increasing the risk of catching aspiration pneumonitis.

Doctors have pointed out that dust flying all over the place will increase the amount of particles in the air, and inhaling them can irritate the respiratory tract and lead to sneezing or even pneumonia. It is advised that people with asthma, nose allergies or chronic obstructive pulmonary disease avoid events that use powder.

Experts state that cornstarch is the main ingredient of colored-powder and inconsiderate use of it is dangerous. The risk is lower if the dust is contained in a bag and only the surface has contact with the air; but if the powder is sprayed into the air, each particle is heated and chances of explosion increase.

Past international dust explosions:

  • May 2, 1878: The Washburn A Mill Explosion in Minnesota, U.S. led to 22 casualties. It not only destroyed the largest flour mill in the world, but also demolished five other adjacent mills and decreased the city’s production of flour by one-third. The government also considered improving the ventilation system to prevent another dust explosion.
  • April 26, 1942: 1,549 Chinese miners (34% of all the miners) died in the Benxihu Colliery coal-dust explosion, which is one of the worst coal mine disasters in history.
  • 1977: The Westwego grain elevator explosion in Louisiana, U.S.
  • Jan. 29, 2003: The West Pharmaceutical Service rubber dust explosion in Kinston, North Carolina, U.S.
  • Feb. 7, 2008: The sugar refinery explosion of Imperial Sugar in Port Wentworth, Georgia, U.S., led to 14 casualties.
  • Aug. 2, 2014: The Kunshan dust explosion in Jiangsu, China led to 146 fatalities and 114 injured.

Translated by Olivia Yang

Sources:
Health Business Weekly
CommonWealth
Apple Daily