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Interpretation Response #02-0092 ([SENSIDYNE] [Ron Roberson])

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

Interpretation Response Details

Response Publish Date:

Company Name: SENSIDYNE

Individual Name: Ron Roberson

Location State: FL Country: US

View the Interpretation Document

Response text:

Feb 13, 2003

Mr. Ron Roberson                 Reference No. 02-0092
Corporate Industrial Hygienist & Technical Manage
16333 Bay Vista Drive
Clearwater, FL 3376088

Dear Mr. Roberson:

This responds to your letter regarding the small quantity exceptions under the Hazardous Materials Regulations (HMR: 49 CFR Parts 171-180), as they apply "smoke tubes" sold by your company.  We apologize for the delay in responding and hope it has not caused any inconvenience.

According to your letter, the smoke tubes are used to track air currents in ventilation studies and to test respirators for proper fit in accordance with OSHA standards for irritant fume respirator fit test protocol.  Each smoke tube consists of a pencil-sized sealed glass tube filled with pumice granules coated with approximately one gram per tube of "Stannic chloride, anhydrous, 8, UN 1827, II" The tubes are activated by breaking off the ends and pushing ambient air through with a small rubber bulb or motorized pump.  Moisture in the air reacts with the stannic chloride and produces the smoke.  The smoke tubes are sold in a box of ten tubes.

A material described as "Stannic chloride, anhydrous, 8, UN 1827, II" may be transported under the small quantity exception if it meets the quantity limits and packaging requirements in § 173.4, and is not forbidden under § 173.21. Based on the description of the "smoke tubes", it is our opinion that they may be transported under the small quantity exception provided the quantity of the Class 8 (corrosive) material in the inner packaging (i.e., glass tube) is less than 30 grams (1 ounce) and all other provisions of § 173.4 are met.  A package shipped in accordance with the small quantity exceptions in § 173.4 is not subject to any other requirements of the HMR, including labeling.  The "smoke tubes" may also be shipped under the limited quantity exceptions for corrosive materials in § 173.154, which excepts such packages from the labeling requirements, unless offered or intended for transportation by aircraft.

I hope this satisfies your inquiry.  If we can be of further assistance, please contact us.


Delmer F. Billings
Chief, Standards Development
Office of Hazardous Materials Standards


Regulation Sections

Section Subject
173.4 Small quantities for highway and rail