OSHA’s PSM standard requires Operating Procedures to address “special or unique hazards”
1910.119(f)(1)(iii) Safety and health considerations:
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1910.119(f)(1)(iii)(E) Any special or unique hazards.
This item is often not necessary with many of the PSM standard’s Highly Hazardous Chemicals; however, HFO-1234yf has a unique property that falls into this requirement. HFO-1234yf is…
a Category 1 Flammable Gas that is “Non-Odorized”. This means that HFO-1234yf has no warning properties that workers will be able to detect with their senses. A worker would have no ability to recognize they are in the presences of a flammable atmosphere and this is certainly special or unique. I have yet to get a response from the manufacturers of HFO-1234yf as to why an odorant is not added to this Category 1 Flammable Gas refrigerant, but currently, it is “non-odorized”. What does this mean to the users who have over 10,000 pounds in their process?
The employer is going to need to address this “special or unique hazard” in their process design, as well as their Operating Procedures. The straight forward answer is to install gas detection devices for this material. Taking into consideration that this material has a vapor density of 4 (Air=1) the placement of these meters is simple… ground level or any locations below grade in the proximity of where the material is stored/handled. The manufacturer’s offer some guidance on how to set up a leak detection system and there are detection systems made for this type of refrigerant. There may even be a need for personal detectors for certain tasks such as line break/process opening in areas where there are no fixed detectors.
I will discuss my thoughts on PPE needs, specifically Flame Retardant Clothing, in a later post.