DHS Clarifies Propane Mixture Rule

Today DHS published in the Federal Register a clarification on the CFATS rules for calculating STQ quantities for mixtures containing propane. According to the notice signed by Robert Stephan, Assistant Secretary for Infrastructure Protection;

 

“Since publication of the Appendix A Final Rule, the Department has received numerous inquiries about the STQ provisions for the COI propane and about the applicability of the release-flammable mixture provisions to products that contain the COI propane and to other products that contain some propane. To respond to those inquiries and alleviate any confusion, the Department is publishing this notice to provide clarification on this matter.”

 

Another Propane Problem

 

Apparently the problem is that what is commonly called ‘Propane’ (this is my usage to avoid confusion) is actually a mixture of flammable gasses, at least 87.5% of which is generally the actual chemical propane. Other chemicals commonly included are butane, ethane, and pentane (among others). Under the flammable release mixtures rule, if any of these other chemicals were present in amounts in excess of 1%, the total mixture would have to be reported for those chemicals if the total amount of the mixture met the STQ for that material.

 

Normally this is not a problem. The flammable mixture would only get reported on the Top Screen one time, under the name of the chemical that made up the largest part of that mixture. Once again, the fact that propane is an exception to the rules has come back to bite DHS. The STQ for propane is much larger than for the other chemicals, so the propane in the mixture might not be reportable on the Top Screen, but the other chemicals would be.

 

To make it even more confusing, propane in tanks smaller than 10,000 pounds does not have to be counted in the STQ calculations at all. The same does not hold true for the compounds in ‘Propane’.

 

The Clarification

 

So DHS issued today’s ‘clarification’ of the rule; ‘Propane’ (with at least 87.5% propane) will be treated as a unitary chemical not as a mixture. The other chemicals that make up the mixture known as ‘Propane’ will not be considered as separate constituents under the flammable release mixture rule.

 

To make this ‘perfectly clear’ DHS adds this statement at the end of the Federal Register Notice:

 

“The statement in the Appendix A Final Rule preamble that the mixtures provisions for propane are the same as for all other release-flammables, 72 FR 65407, should be read in this intended context. Since it would not be logical or reasonable to apply the release-flammable mixtures provision to the COI propane (products containing at least 87.5% propane), the preamble statement was intended to cover mixtures containing less than 87.5% propane.”

 

This is what happens when regulatory agencies try to prepare reasonable regulations based on logic and science and then allow the politicians to muddy the waters when they pander to special interest groups.

Tags: Chemical Facility Security, Propane Rules, Flammable Release Mixture Rule