1
The bananas give off ethylene, a clear, odorless gas that promotes ripening.
2
Free nitrogen, like oxygen, is a colorless, odorless gas.
3
Woodruff himself could permeate like an odorless gas; you knew he was there only by the results.
4
A leak of large amounts of the colorless and odorless gas naturally found in low density in the atmosphere could have devastating consequences.
5
Meanwhile leaks from store wells and pipelines of the invisible, odorless gas -which can suffocate -are a possible concern downplayed by analysts.