ABSOLUTELY! One of my engineering managers early in my career was the founder of the “engineering geek squad” and was an absolute stickler for details when it came to technical matters. He always told me I was driving him to the insane asylum with my improper interchangeable use of the terms “vapor” and “gas” when referring to our HAZMATS. To this day, I remember my “white board session” with him in 1994 regarding the difference between these terms and how “as a safety engineer, my improper use of these basic terms was improperly teaching people who may not realize there is a difference”. Here is, what may be the best teaching moment of my career, I learned in that session…
A “gas” is a airborne at standard temp and pressure. So when we store it as a liquid under pressure or by refrigeration, when we loose either the pressure or refrigeration it goes BACK TO BEING A GAS as it wanted to always be a gas.
A “vapor” is what comes off a liquid’s surface due to its vapor pressure being greater than atmospheric/container pressure, but. It high enough to be a “gas”. When we loose the pressure, the liquid does not go to a “gas”, instead, it eVAPorates and produces a VAPOR.
So Anhydrous Ammonia is a GAS, not a vapor. I was reminded of my time in the engineering managers office as I listened in on a conference call updating a recent NH3 release when the govt official on the call corrected the local official(s) to stop referring to the “gas” as a “vapor” and when the local official sort of blew it off “as we have bigger issues to deal with” and said “it doesn’t matter”, this federal govt official sounded like a twin of my former engineering manager and “corrected the record”.
There is ABSOLUTELY a difference and it DOES MATTER! I still make the mistake today, but that little voice in my head will remind me when I incorrectly refer to a gas as a copier or a vapor as a gas. Many thanks to Roy McKinney at Westvaco-Chemical for taking so much of his time to teach my dumb ass about HAZMATs.