I had to wear an oxygen mask both in the water and on land because of the carbon monoxide. I fainted four times during the first day of filming. We were shooting the scene in which Godzilla emerges from the water as he approaches Hong Kong. I wasn't warned about the carbon monoxide, so I wasn't wearing an oxygen mask. We were shooting in water, so nobody could just run up to me when they saw me acting strangely. We were filming a long shot, so nobody was very close to me. The members of the staff didn't realize I'd fainted that first time until they started opening up the costume so I could get out.
As quoted by David Milner, "Kenpachiro Satsuma Interview III", Kaiju Conversations (December 1995)