21.   In a time of increased danger from terrorist bombings, requiring the taggants in explosive materials is common sense.

22.   In an explosion, a chemical reaction transforms the explosive material into gas.

23.   In May, police arrested a man with a Nazi fixation after finding explosive materials in his home near the Olympic site.

24.   In the trunk of his car were nitroglycerine, timing devices and enough explosive material to flatten a building.

25.   In the meantime, the X-ray machines used at check-in security points will at least show when a shoe has been hollowed out to conceal explosive material.

26.   It also does not include provisions to lace explosive materials with an identifying code that would make tracing easier.

27.   It would also ease the rules for deporting aliens suspected of terrorist acts, and require tagging explosive materials to make them easier to trace.

28.   Kaczynski was charged last week with illegal possession of explosive materials.

29.   Law enforcement officials said on Wednesday that laboratory tests of airplane parts have not confirmed the presence of explosive material, even though some preliminary tests had showed traces.

30.   Officials said that explosive materials are used and removed after the testing.