There are 631 fewer RMP covered processes with Anhydrous Ammonia since 2011. This translates to a reduction of right at 78 million pounds in anhydrous ammonia in reported RMP covered processes. This took anhydrous ammonia from a clear #1 in pounds in RMP covered processes in 2011 down to #3 in 2017 (see tables below). What drove such a reduction? Could it be that OSHA and EPA’s process safety standards are actually having the impact they had hoped for… reducing inventories and thus reducing the severity of a catastrophic release. It would be interesting to dig deeper and determine what drove such a large reduction in inventories of NH3. Considering that the “# of facilities” are most likely driven by refrigeration processes and the “pounds in process” are most likely driven by fertilizer facilities with atmospheric cryogenic storage tanks I am guessing that this 78 million pounds reduction could be as simple as 1-2 of these atmospheric cryogenic storage tanks being removed from service. A quick glance of “deregistered” sites tells us that the vast majority of sites with NH3 as their RMP chemical were fertilizer distributors, but this was NOT a scientific analysis, just merely a scroll down the list and it was very obvious that the fertilizer industry contributed greatly to this reduction. Why? Did OSHA’s June 2015 Letter/Memo changing the definition of “retail” have this big of an impact? Although the courts over-ruled OSHA on the definition of “retail”, was the damage already done? Anyway you look at it, a reduction of 77,980,065 pounds of any HHC/EHS is a serious reduction in risks.
Here are the Top 10 Chemicals as reported in the RMP Database in 2017 (sorted by pounds):
| Chemical Name | Chemical Type | # of facilities | Pounds in processes |
| Flammable Mixture | Flammable | 870 | 39,550,554,048 |
| Propane | Flammable | 642 | 11,995,738,779 |
| Ammonia (anhydrous) | Toxic | 7,041 | 10,490,688,224 |
| Butane | Flammable | 409 | 8,738,616,637 |
| Ethane | Flammable | 62 | 2,777,226,840 |
| Isobutane [Propane, 2-methyl] | Flammable | 204 | 2,285,294,836 |
| Propylene [1-Propene] | Flammable | 147 | 1,514,567,396 |
| Ethylene [Ethene] | Flammable | 89 | 1,075,976,239 |
| Chlorine | Toxic | 2,429 | 846,866,511 |
| 2-Methylpropene [1-Propene, 2-methyl-] | Flammable | 43 | 799,951,365 |
And here is the same analysis from 2011 (sorted by pounds)
| Chemical Name | Chemical Type | # of facilities | Pounds in processes |
| Ammonia (anhydrous) | Toxic | 7,672 | 182,886,947,607 |
| Flammable Mixture | Flammable | 669 | 33,886,809,199 |
| Toluene 2,6-diisocyanate [Benzene, 1,3-diisocyanato-2-methyl-] | Toxic | 12 | 27,203,174,821 |
| Propane | Flammable | 683 | 10,394,499,163 |
| Butane | Flammable | 293 | 8,291,382,260 |
| Cyclohexylamine [Cyclohexanamine] | Toxic | 40 | 4,611,868,904 |
| Isobutane [Propane, 2-methyl] | Flammable | 212 | 2,528,587,729 |
| Ethylene [Ethene] | Flammable | 84 | 1,805,006,405 |
| Ethane | Flammable | 65 | 1,298,227,831 |
| Propylene [1-Propene] | Flammable | 142 | 1,069,906,503 |
