Ms. Carmen Morrow
Rolls-Royce North America
2001 S. Tibbs Avenue: Speed Code S36
Indianapolis, IN 46241

RE: The tariff classification of an article of insulating mineral materials

Dear Ms. Morrow:

In your letter dated September 17, 2010, you requested a ruling regarding the classification of part number 23059513 described as a “thermal insulation blanket.”

You stated that this product consists of ceramic fiber (mineral wool) pads encapsulated in one-inch woven textile squares covered with an outer cladding of stainless steel.

Your letter indicates that the item will be used in a gas turbine engine to protect the rear turbine support hub from excessive heat produced by the turbine.

A sample was submitted with your ruling request. The sample was submitted to our Customs and Border Protection Laboratory for analysis. Our laboratory has now completed its analysis.

Our laboratory has verified that the insulating material (padding) in this product consists principally of ceramic fibers (aluminum silicate mineral fibers) but also includes a smaller percentage of glass fibers; the article also contains smaller amounts of other components.

In your letter you asked whether the product was classifiable in Chapter 68 or Chapter 70 of the Harmonized Tariff Schedule of the United States (HTSUS). This article contains both glass fibers of Chapter 70 and mineral fibers of Chapter 68. If an insulating product consisting of both glass fibers and mineral fibers was found to contain more glass fibers than mineral fibers, heading 7019 of the HTSUS would apply. However, based on the conclusion by our laboratory that the mineral fiber component - not the glass fiber component – is predominant in the submitted sample of the insulating product, the submitted item is classifiable in heading 6806, HTSUS.

Heading 6806 applies to this sample because the mineral fibers appear to predominate in the sample. These mineral fibers (mineral wool) impart the essential character of this sample.

Based on our laboratory analysis of the submitted sample, the applicable subheading for this article of insulating mineral materials - part number 23059513 - will be 6806.10.00, HTSUS, which provides for slag wool, rock wool and similar mineral wools (including intermixtures thereof) in bulk, sheets or rolls. The rate of duty will be 3.9 percent ad valorem

Duty rates are provided for your convenience and are subject to change. The text of the most recent HTSUS and the accompanying duty rates are provided on World Wide Web at

This ruling is being issued under the provisions of Part 177 of the Customs Regulations (19 C.F.R. 177).

A copy of the ruling or the control number indicated above should be provided with the entry documents filed at the time this merchandise is imported. If you have any questions regarding the ruling, contact National Import Specialist Jacob Bunin at 646-733-3027.


Robert B. Swierupski
National Commodity
Specialist Division