Correction

British Medical Journal, March 31, 2001

Explosions may occur if dry ice is placed in airtight transport containers

An error occurred in this letter by Sally Sharp and colleagues (17 February, p 434). In the second sentence of the fourth paragraph the wrong conversion factor was used to convert vapour pressure from bars to the SI unit of Pascals, the correct factor being 1 bar = [10.sup.5] Pa. The sentence should read: "When warmed to 20 [degrees] C solid carbon dioxide exerts a huge vapour pressure (5730 kPa [57.3 bar; not 28.7 Pa as published]), yet the safety data sheet of at least one manufacturer and the Health and Safety Executive's website (www.open.gov.uk/ hse/hsehome.htm) contain no reference to the explosion hazard."