Exploding trousers

In New Zealand in the 1930s, farmers reportedly had trouble with exploding trousers as a result of attempts to wipe out the weed ragwort. Farmers had been spraying sodium chlorate, a government recommended weedkiller, onto the ragwort, and some of the spray had ended up on their clothes. Sodium chlorate is a strong oxidizing agent, and reacted with the organic fibres (i.e. the wool and the cotton) of the clothes. Reports had farmers' trousers variously smouldering and bursting into flame, particularly when exposed to heat or naked flames. [cite news|title=Dr Watson and the exploding trousers|date=2005-10-10|url=http://masseynews.massey.ac.nz/2005/Massey_News/issue-18/stories/11-18-05.html|publisher=Massey University] cite news|title=Exploding Trousers|date=2004-12-18|work=The Science Show|url=http://www.abc.net.au/rn/science/ss/stories/s1264069.htm|publisher=ABC]

One report had trousers that were hanging on a washing line starting to smoke. There were also several reports of trousers exploding while farmers were wearing them, causing severe burns.

The mystery of the exploding breeches was solved by James Watson of Massey University, New Zealand, whose research found that sodium chlorate becomes violently explosive when combined with organic fibres, such as cotton or wool. For his research, Mr. Watson was awarded the 2005 IgNobel Prize in agricultural history.cite news|title=Mr Buckley's exploding trousers and other scientific observations|date=2005-09-15|url=http://www.bmj.com/cgi/content/full/331/7521/865-c?etoc|publisher=BMJ]

On television

The popular U.S. television show "MythBusters" investigated the idea that trousers could explode based on the events of New Zealand in the 1930s. Experimenters tested four substances on 100% cotton overalls:
* A paste comprising a mixture of gunpowder and water (since gunpowder by itself does not cling to clothing)
* An (un-named) "herbicide from the 1930s"
* An (un-named) "fertilizer from the 1930s" (this was most likely ammonium nitrate, the bottle was in the foreground of the shot and the label was facing the camera).
* An acid (to make nitrocellulose/guncotton)

Each of these were put to four different ignition methods: flame, radiant heat, friction and impact.

Although not naming "the herbicide" as sodium chlorate, they confirmed that trousers would indeed vigorously combust due to flame, radiant heat and impact (but not friction). However, combustion is not the same as an explosion, which requires compression and a detonation. Even so, a person witnessing such an event (especially if he or she were wearing the trousers) would likely describe the event as an explosion.

The tests also revealed that none of the other three substances caused combustion of the trousers, thus indicating that sodium chlorate was almost certainly responsible for the events that occurred. [cite web|url=http://kwc.org/mythbusters/2006/05/exploding_trousers_great_gas_conspiracy.html|title=Episode 53: Exploding Trousers, Great Gas Conspiracy|work=Unofficial MythBusters: Episode guides|publisher=|author=|date=2006-05-28]

ABC's "The Science Show" described exploding trousers as "the scenario for a Goon Show", and, in an example of art imitating life, it actually was. The Goons wrote a script about a chemical which "when applied to the tail of a military soldier shirt, is tasteless, colourless, and odourless" but that "The moment the wearer sits down, the heat from his body causes the chemical to explode.". [cite web|url=http://www.thegoonshow.net/scripts_show.asp?title=tales_of_mens_shirts|title=Tales of Men's shirts|work=The Goon Show]

In the final episode of Blackadder Goes Forth, Captain Edmund Blackadder says that he's "Off to Hartlepool to buy a pair of exploding trousers" when feigning madness to avoid going Over the top.

References

Further reading

* The author won an Ig Nobel Prize in 2005 for this paper.