The U.S. Dept. of Transportation (DOT) is revising its requirements for a RIN to include all retesters regardless of the method of testing (modified hydrostatic testing [proof pressure], full hydrostatic testing in a water jacket or visual inspection only). Previously the RIN was required only when performing a water jacket test with determination of total and permanent expansion. The regulations are still being revised - at this time the RIN is not required to be marked on cylinders requalified by the proof pressure type test but the test facility must possess the RIN. When completely revised, all requalified cylinders will have to be marked with the RIN regardless of the requalifying method used.

Details for obtaining a RIN can be found in 49CFR, Section 173.34(e)(iv) but basically this is what you must do:

1. Write to the following address for your initial request for an application:

Associate Administrator for Hazardous Material Safety
U. S. Department of Transportation
Washington, DC 20590-0001

In your request for application, state the type of testing you will be performing (ie. proof pressure testing, water jacket testing or visual inspection only).

2. The DOT will send you an application and list of approved independent private inspection agencies. You will be required to contact one of the inspection agencies and have them audit your test facilities. The independent inspector then will write a letter of recommendation to the DOT based upon his assessment of your test equipment and procedures as well as your knowledge of the DOT regulations.

If you are not familiar with the requirements, most independent inspectors will consult with you on all of the details for an additional fee. This is what you will need:

a. Test equipment (including pressure gauges) that is in compliance with DOT regulations and the Compressed Gas Association (CGA) Pamphlet C-1, Methods of Hydrostatic Test.

CGA booklets are available from:

Compressed Gas Association
1725 Jefferson Davis Highway, Suite 1004
Arlington, VA 22202-4102

b. Copies of CGA Pamphlet C-6 and others as they relate to the type of cylinders you expect to be testing.

c. An adequate calibration control system for pressure gauges used in performing hydrostatic tests.

Note: Pressure gauges used for proof pressure testing must be accurate within 1% of the test pressure. Gauges used for volumetric expansion testing must be capable of ½% accuracy and burrettes ½% (or 0.1 cubic centimeter) accuracy.

d. A good working knowledge of your test equipment and the DOT requirements for requalification of pressure vessels.

3. Upon receipt of your application and a letter of recommendation from the independent inspection agency, the Research and Special Projects Administration (RSPA) of the DOT will issue a RIN to you. The RIN is valid for five (5) years. You must make application to renew your RIN at least 50 days before it expires.