Custard powder, a common household ingredient used to prepare desserts, has a hidden and dangerous potential—it can act as a powerful explosive under certain conditions. While this may seem surprising, history has witnessed several devastating explosions caused by powdered food substances, including flour and cornstarch.
One such incident occurred on November 18, 1981, at the Bird’s Custard factory in Oxfordshire. A hopper of custard powder overflowed, creating a dust cloud that ignited and exploded, injuring nine workers. While the injuries were not fatal, the incident highlighted the lethal risk of dust explosions in industrial settings.
Similar accidents have had catastrophic consequences. In 1871, a flour mill explosion in Minnesota killed 14 people. In 1919, a cornstarch explosion in Cedar Rapids, Iowa, claimed 44 lives and leveled parts of the town. More recently, in 2014, a dust explosion in a factory in Kunshan, China, killed 97 people. A 2022 industry report recorded 50 such explosions worldwide, not all involving foodstuffs, but all demonstrating the dangers of airborne powder ignition.
The science behind these explosions lies in the properties of powdered substances. For an explosion to occur, the powder must be combustible. Flour, cornstarch, sugar, coal dust, powdered plastic, and even aluminium powder can ignite when airborne, increasing their surface area exposed to oxygen. When ignited—often by friction, static electricity, or another heat source—a fire can spread almost instantaneously, resulting in an explosive force.
At the Bird’s Custard factory, workers noticed cornstarch spilling from a bin. Moments later, a flash was seen, followed by a fiery explosion. An accident report described the event as a “gale-force wind with a flame front behind, flashing through the area.” Investigations later revealed a malfunction in the machinery responsible for distributing cornstarch, which led to an overflow and the subsequent ignition.
To mitigate the risks of such explosions, factories implement stringent safety measures, including grounding equipment to prevent static electricity, installing filtration systems to remove airborne dust, and conducting regular inspections to prevent dust buildup.
The dangers of combustible powders are not limited to industrial settings. In 2015, a festive event at a water park in Taiwan turned tragic when colored cornstarch sprayed over a crowd ignited, injuring more than 500 people and resulting in 20 deaths. These incidents serve as stark reminders of the hidden hazards lurking in seemingly innocuous substances.
While custard powder remains a beloved ingredient in many kitchens, its explosive potential underscores the importance of proper handling and awareness, especially in industrial environments. What appears to be a harmless dessert staple can, under the right conditions, become a force of destruction.
