31.   This shutdown does not necessarily threaten the safety of the shuttle crew, but hydrogen gas can be released through the engine nozzle.

32.   Twelve people were killed when a Japanese cult released sarin gas on a subway.

33.   Urea-tripolymer has a low fire-hazard rating, but some environmentalists are concerned that it could release formaldehyde gas into the house over time.

34.   Volatile gases are released, and organs liquefy and complex fats and proteins are broken down, but so far no one has quantified this process.

35.   When combined with liquid, it releases carbon dioxide gas.

36.   Police blocked off streets and evacuated residents after an explosion Thursday at an ice company plant released ammonia gas.

37.   Poisonous gas was accidentally released early Saturday in southwestern Hungary, leading authorities to order the evacuation of three villages, the MTI news agency reported.

38.   A cleaning woman found a homemade device before its timer could release lethal gas into a Tokyo subway station at rush hour Tuesday evening, police said.

39.   A device that could have released lethal gas was found in a Tokyo subway station Tuesday night, but no one was hurt, police said.

40.   A device that could have released lethal gas was found in a Tokyo subway station at rush hour Tuesday evening, but no one was hurt, police said.