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Clarification to Chemical Facility Anti-Terrorism Standards; Propane

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Department of Homeland Security.




This notice clarifies how certain provisions of the Chemical Facility Anti-Terrorism Standards (CFATS) apply to the Chemical of Interest (COI) propane, which the Department of Homeland Security (DHS or Department) understands to contain at least 87.5% of the chemical propane. Specifically, this notice clarifies how the Screening Threshold Quantity and certain counting rule provisions apply to the COI propane.


Effective Dates: Effective March 21, 2008.

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Dennis Deziel, Infrastructure Security Compliance Division, Department of Homeland Security, 703-235-5263.

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Section 550 of the Homeland Security Appropriations Act of 2007 provided the Department with authority to promulgate interim final regulations for the security of certain chemical facilities in the United States. See Pub. L. 109-295, sec. 550. On December 28, 2006, the Department issued an Advance Notice of Rulemaking seeking comment on the significant issues and regulatory text (see 71 FR 78276) for such rulemaking, and on April 9, 2007, the Department published an Interim Final Rule (IFR) establishing the Chemical Facility Anti-Terrorism Standards (CFATS), 6 CFR Part 27 (see 72 FR 17688).

The IFR, except for Appendix A to Part 27, went into effect on June 8, 2007. Appendix A to the IFR contained a tentative list of Chemicals of Interest (COIs) and corresponding Screening Threshold Quantities (STQs). DHS accepted comments on the tentative list of COIs and STQs. In an Appendix A Final Rule published on November 20, 2007, the Department responded to the many comments received and provided a final list of COIs and STQs. See 72 FR 65396. Pursuant to 6 CFR 27.210(a)(1)(i), any facility that possesses any of the COIs listed in Appendix A at or above any applicable STQ must complete and submit a Top-Screen questionnaire to DHS. See 6 CFR 27.200(b)(2).

Among other revisions to the final Appendix A, DHS set a special STQ for the COI propane.[1] DHS listed the COI propane as a release-flammable COI with an STQ of 60,000 pounds; this is in contrast to the 10,000 pound STQ that DHS used for most other release-flammable COI.[2] In addition, the Appendix A Final Rule included a special rule for calculating whether a facility meets the STQ for the COI propane.[3] The reasons for the unique STQ provisions for the COI propane are detailed in the preamble to the Appendix A Final Rule. See 72 FR 65406-65407, 65409-65410.

The Appendix A Final Rule also included provisions on how facilities should treat mixtures of COI (known as the mixtures provisions). See 6 CFR 27.204. Under certain conditions, 6 CFR 27.204(a)(2) (the release-flammable mixtures rule) provides that if a release-flammable COI is present in a mixture in a concentration equal to or greater than one percent by weight, the facility shall count the entire amount of the mixture toward the STQ for that COI.

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.

The Appendix A Final Rule was drafted with the understanding that the COI propane consists predominantly of the chemical propane, in combination with other flammable gases—such as butane, pentane, ethane, and/or propylene (which are also release-flammable COI under Appendix A). That understanding was likewise in mind when the Department developed the special STQ (i.e., 60,000 pounds) and STQ counting rule for the COI propane (see 6 CFR 27.204(b)(3)). It was, and is, commonly understood, however, that not every product containing any amount of the chemical propane is considered “propane” for commercial or other purposes.

As is well-known, the COI propane typically consists predominantly of the chemical propane in combination with other release-flammable COI, as noted above.[4] Within the propane industry, it is very typical for the COI propane to contain at least 87.5 percent of the chemical propane. This is reflected in the Material Safety Data Sheets (MSDS) for Odorized Propane of many propane companies as well as in the model MSDS from the National Propane Gas Association (NPGA).[5] This is consistent with DHS's understanding of the COI propane.

Since DHS intends the COI propane to refer to products containing at least 87.5 percent of propane, as well as other release-flammable COI, it follows that the release-flammable mixtures rule does not apply to such products. In fact, it would not make sense to apply the release-flammable mixtures rule to the combination of chemicals that constitute the COI propane because that would largely negate the intended effect of the 60,000 pound STQ and the special STQ counting rule for the COI propane.[6] By contrast, the release-Start Printed Page 15052flammable mixtures rule does apply to products that are a combination of less than 87.5 percent propane and other release-flammable COI, since such mixtures are not themselves the COI propane.[7]

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Robert Stephan,

Assistant Secretary for Infrastructure Protection, Department of Homeland Security.

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1.  In this notice, DHS clarifies what is meant by the Chemical of Interest propane (or COI propane), as opposed to other products that contain some amount of the chemical propane.

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2.  In the tentative list of chemicals in the IFR, DHS had suggested an STQ of 7,500 pounds for all release-flammable COI, including the COI propane. See 72 FR 17743 (April 9, 2007).

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3.  Under 6 CFR § 27.203(b)(3), in calculating whether a facility possesses an amount that meets the 60,000 pound STQ for the COI propane, a facility need not include propane in tanks of 10,000 pounds or less.

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4.  The COI propane may also contain relatively small amounts of additives (such as odorants) or contaminants.

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5.  The model MSDS from NPGA can be found on the NPGA Web site at​files/​public/​Tech_​Bulletin_​NPGA_​210-96.pdf.

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6.  For example, if a combination of 90% propane and 10% butane were subject to the release-flammable mixtures provision, as little as 10,000 pounds of that product would meet the STQ for butane, and thus trigger the Top-Screen reporting requirement of CFATS. This effect would be inconsistent with the purpose of the special 10,000 pound counting rule and the 60,000 pound STQ for the COI propane and with DHS's express intent not to subject facilities to the Top-Screen requirement when the only COI that would otherwise trigger that requirement is less than 60,000 pounds of COI propane. See 72 FR 65406-65407, 65409-65410.

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7.  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.

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[FR Doc. 08-1059 Filed 3-18-08; 12:04 pm]