why does Geordi...

[cardinal biggles]

One would think so, since they're dropping an isolation door. The layout of Engineering is never really established well on-screen, but there do seem to be multiple doors in or out, so maybe this is just to keep all that billowing smoke from drifting out into the corridor.

 

[Dayton3]

One of Star Trek's great myths is that antimatter coming into contact with matter would produce some huge, nuclear type explosion.

According to Dr. Robert L. Forward in his book "Mirror Matter" in all likelihood, when matter and antimatter came into contact, all the energy would be released as radiation and highly energetic particles that would NOT react with normal matter very well.

Instead of a "BANG!!!" it would be more like "poof".

 

[Kryton]

Yeah, but focus a matter/anti-matter mix through dilithium and it changes the entire thing. Perhaps even so much it might kill someone making a risky adjustment at a last minute emergency need.