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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #04-0065 ([Phoenix Air] [Mr. Dent Thompson])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: Phoenix Air

Individual Name: Mr. Dent Thompson

Location State: GA Country: US

View the Interpretation Document

Response text:

Mar 24, 2004


Mr. Dent Thompson                Reference No. 04-0065

Vice President, Operations

Phoenix Air

100 Phoenix Air Drive, SW

Cartersville, Georgia 30120

Dear Mr. Thompson:

Your March 5, 2004 letter to Mr. Jackson Smith, Federal Aviation Administration Southern Region, has been referred to this office for response.  In your letter, you assert that a representative of the Office of Hazardous Materials Standards, Research and Special Programs Administration, told you that air carriers are excepted from the security plan requirements in Subpart I of Part 172 of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180).

I want to apologize for any confusion that has resulted from your inquiry about the applicability of the security plan requirements to air transportation.  The staff member who you spoke to was in error.  The security plan requirements in Subpart I of Part 172 apply to any person who offers for transportation or transports in commerce one or more of the following hazardous materials:

  1.         A highway-route controlled quantity of a Class 7 material in a motor vehicle, rail car, or freight container;


  1.         More than 25 kg (55 pounds) of a Division 1.1, 1.2, or 1.3 material in a motor vehicle, rail car, or freight container;
  1.         More than one L (1.06 qt) of a material poisonous by inhalation that meets the criteria for Hazard Zone A;


  1.         A shipment in a bulk packaging having a capacity equal to or greater than 13,248

L (3,500gallons) for liquids or gases or more than 13.24 cubic meters (468 cubic feet) for solids;

(5)        A shipment in other than a bulk packaging of 2,268    kg (5,000 pounds) gross weight or

            more of one class of hazardous material for which placarding of a vehicle, rail car, or 

            freight container is required under the provisions of Subpart F of Part 172;

(6)         A select agent or toxin regulated by the Centers for Disease Control and Prevention; or


  1.         A quantity of hazardous materials that requires placarding under the provisions of

             Subpart F of Part 172.


In effect, then, the security plan requirements apply to a shipper or carrier of a hazardous material in an amount that requires placarding and to select agents.  As we stated in the preamble to the final rule that established the security plan requirements, using the placarding thresholds to trigger enhanced security requirements covers the materials that present the most significant security threats in transportation and provides a relatively straightforward way to distinguish materials that may present a significant security threat from those than do not.

The security plan requirements apply to the transportation of hazardous materials by all modes, including by air carrier.  The requirements are triggered by the offering or transportation of a hazardous material in a quantity that requires placarding under Subpart F of Part 172 of the HMR, not by the absence of presence of a placard on a given shipment.  Thus, for an air carrier transporting explosives, the HMR require the air carrier to develop and implement a security plan if the air carrier is transporting a shipment of explosives in an amount that would require placarding if transported by highway or rail.  Thus, if you transport any quantity of a Division 1.1, 1.2, or 1.3 explosive, or more than 454 kg (1,001 pounds) of a Division 1.4, 1.5, or 1.6 explosive, you must have a security plan.  Your exemption, DOT-E-8826, does not exempt you from the security plan requirements.

The HMR permit you to use a security plan that conforms to regulations issued by other Federal agencies to satisfy the security plan requirements in Subpart I of Part 172, provided the plan addresses the requirements specified in Subpart 1. Therefore, you may use your approved Transportation Security Administration (TSA) 12-5 security program to meet your security plan obligations under the HMR.  You must provide your employees who are responsible for implementing the TSA 12-5 security program with in-depth security training in accordance with § 172.704(a)(5) of the HMR.

I hope this information is helpful.  Please contact this office if you have additional questions.



Susan Gorsky

Senior Transportation Regulations Specialist

Office of Hazardous Materials Standards


Regulation Sections

Section Subject
172.800 Purpose and applicability