Screen Shot 2017 10 08 at 5.24.37 PMBack in early 2015, I began working with some clients who were questioning their industry having to enter into the Process Safety arena because of a new refrigerant that was going into automobiles.  Early in our discussions I was appalled that this material had been "marketed and sold" with the description of being a "mildly flammable" gas by, what I once considered to be a highly reputable chemical company.  As someone who has been around HAZMATs since the late 1980's the term "mildly flammable" was new to me, as I had never seen any flammables or even combustibles classed or categorized as "mildly flammable".  As soon as I received the (M)SDS for this material I quickly realized that this refrigerant was indeed an "Extremely Flammable" Gas (e.g. Category 1 Flammable).  This client was in a situation where the refrigerant manufacturer and the manufacturer of the bulk tank skid unit had decided to label the tank with a NFPA Flammable rating of "1".  This caused tons of problems and caused much confusion for this industry and once again caused me to be labeled "crazy", "safety extremist", and the worst... "consultant just trying to get more work".


Source:  Tank Manufacturer Website (not mentioning name of company on purpose)

Another client had labeled their HFO tank as a NFPA Flammable "2" (can't post that pic) and it took me a while to convince this client that HFO-1234yf is without question a NFPA Flammable "4" rating.  In talking with others in the industry and researching other systems built by the same manufacturer of the process equipment it seemed there was a large consensus that this new refrigerant was a "1" or at the most a "2".  After being told by a number of folks that the manufacturer of the refrigerant knew better how to rate their refrigerant than "this crazy safety guy from western KY" (paraphrasing) could ever know about this refrigerant I decided I needed to break this down for the industry.  In August 2015 I decided to make my point to those in the industry who wanted the facts in my post: .  This posting actually led to some angry folks who had some legal issues about my posting asking me to remove the post; my attorney backed me and said anything that was not factual, we would correct, but I was not taking down the post.  One client, I convinced and still work with them today; unfortunately, three others have decided to take different paths in their management of this PSM - Category 1 "Extremely Flammable" Gas.  But last month the manufacturer(s) updated their SDS, yet again, and in this edition, we see they have now included the NFPA and HMIS ratings in which they state this refrigerant is indeed a NFPA Flammable "4".

As I have stated several times, the conversion from R-134a to HFO-1234yf was done with safety blinders on!!!  The sole intent of this conversion was for ENVIRONMENTAL reasons (HFO has a GW# of 5 vs. R-134's of >1,000).  The industry looked at risk based on those posed to the occupants of the automobiles and as far as I can tell never considered the risk of having tens of thousands of pounds of this Cat 1 Flammable Gas on site.   Some clients had some brief discussions years ago about this conversion, but the industry was not really up on the application of OSHA's PSM standard and a lot of those discussions ended with the wrong answer; leaving an entire industry caught with their proverbial "pants down" when this Cat 1 Flammable Gas arrived on site.  One day I am seriously thinking about writing a book about this refrigerant conversion and how the PSM debacle occurred.  Sadly, there will be a few businesses that will ignore this SDS revision and will continue to label their tanks with a "1" or "2" and still claim this material is NOT a PSM flammable and that their process does not fall under PSM.  We can only try to educate those who want to learn!

I was also pleased to see this newest edition also includes a BLEVE warning!  Although they did not use the nasty word BLEVE in their revision, they do make it clear that if the container of HFO-1234yf is exposed to fire the container can rupture.  You can see my Part 3 and 6 articles below was an attempt to educate the industry as to where they should locate their storage tank.

SAFTENG Members can read my HFO-1234yf Series:

HFO-1234yf refrigerant may end up in New Zealand Refrigerators and Home ACs
Managing your HFO-1234yf BLEVE risk (Part 6)
Could HFO-1234yf have a short live span in our car's AC unit?
Refrigerant HFO-1234yf and Flame Retardant Clothing (Part 5)
Refrigerant HFO-1234yf is a PSM HHC with “special or unique hazards” (Part 4)
Is the Refrigerant HFO-1234yf a BLEVE risk? (Part 3)
Refrigerant HFO-1234yf is a Flammable "4" in the NFPA 704 Diamond (Part 2)
Refrigerant HFO-1234yf is a PSM Highly Hazardous Chemical (Part 1)
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