I believe I made the claim here that we didn't use gas during
the Vietnam war.  I've checked with a friend of mine and I
stand corrected:

begin quote

We used tear gas (or Riot Control Agents) fairly extensively.  It was quite
common to carry tear gas grenades to use in tunnels,
and we were issued a light-weight mask, known as an RCA Mask, to carry in
lieu of the heavier M17 Mask.  VC tunnels sometimes did have water traps --
especially in the huge tunnel complex at
Cu Chi.  Randy Ellis, "Tunnel Rat 6" was a good friend of
mine, and used to talk about it quite a bit.

end quote

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