Imagine the purchasing manager announcing at a staff meeting that the business is changing the supplier for one of your PSM/RMP-covered chemicals. There is nothing special about this chemical; it is a 100% pure solution/gas, so you think nothing is changing. But this chemical has come under a lot of questions by yours truly, and in fact, a simple change in vendor will impact the Process Safety Information (PSI) in the following way(s):
The refrigerant known as HFO-1234yf (2,3,3,3-Tetrafluoropropene) continues to cause a stir within the PSM arena. I still find organizations that insist this refrigerant is “mildly flammable” and therefore is not a PSM chemical. Even after I show them, using their very own SDS, that in fact it is “Extrememy Flammable”. I also now have a LOI from OSHA that makes it clear this is a PSM covered flammable gas (e.g. Cat 1 Flammable Gas). The NFPA 704 ratings for this chemical have been all over the place! If you have foolwed my writings for the past 10 years or so you are well informed on this matter. Several clients argued that this CAT 1 flammable gas had a NFPA fire rating of a “1”; which is impossible when we look at NFPA’s definition of a “4”. And its not only the Fire rating that has gone from 1 to 4; the health rating is now doing some dancing. I can find SDS’s that state the health rating ranges from a “1” to a “3”.
And these variations in the NFPA 704 ratings is what will cause the end user to make changes. Remember, our PSI requires us to have the chemical information; we can use an SDS as long as that SDS provides ALL the required data (which most do not). We also have to LABEL our bulk storage tank(s) in some acceptable manner. Most businesses uses the NFPA 704 Diamond and when we change vendors who have different NFPA 704 ratings, this would infact require an MOC so that we can update/revise our Tank (and Building doors) labeling to reflect the new/revised NFPA 704 numbers.