#Coleman mantles portable#
#Coleman mantles license#

Population from Consumer Products and Miscellaneous Sources. Radioactivity Released from Burning Gas Lantern Mantles. (1) Any quantities of thorium contained in (i) incandescent gas mantles,

#Coleman mantles license#

(c) Any person is exempt from the regulation in this part and from the requirements for a license set forth in section 62 of the Act to the extent that such person receives, possesses, uses, or transfers: Pertinent Regulationsġ0 CFR 40.13 Unimportant quantities of source material (2003) The highest exposure, 200 mrem per year, was to a hypothetical individual who lived in a residence for 4800 hours per year in which the only source of light was four gas lantern mantles.Ī dose of 2 mrem was calculated for a small child who played with a used mantle and ingested part of the ash.Īvid campers were estimated to receive 0.05 to 6 mrem per year, while the estimate for one-time campers was 0.002 to 0.06 mrem. The inhalation doses were based on the assumption that all of the Rn-220 in the mantle was released and that 30 % of the radium was volatilized when the mantles were ignited. Estimates of the Radiation ExposuresĪ very detailed analysis of the radiation exposures due to thorium containing gas lantern mantles can be found in section 3.4 of the Nuclear Regulatory Commission publication “Systematic Radiological Assessment of Exemptions for Source and Byproduct Materials” (NUREG-1717). in 2000 (or thereabouts), contained thorium. According to NUREG-1717, about half of the 50 million mantles sold in the U.S. The yttrium mantle produces about 20% less light, but it lasts longer. Sometime around 1990, the Coleman Company replaced the thorium in their mantles with yttrium. was 20 million in 1974, 25 million in 1981 and 50 million in 2000. It has been estimated that the annual production/sales of mantles in the U.S.

In 1952, approximately 65 % of the thorium produced in the U.S. Luetzelschwab and Googins measured a total of 0.065 uCi in two mantles. They noted that some mantles contained up to 400 mg. Nevertheless, NUREG-1717 assumed that a typical mantle contained 250 mg (0.027 uCi) for the purpose of its dose calculations. I have not seen much quantitative information about the thorium content of the mantles. The material becoming airborne includes approximately 50 % of the beryllium and many of the radioactive decay products of the thorium. When the mantle is heated up for the first time (a cure), the thorium is converted to thorium oxide, the lacquer is burned off, and a variety of materials are released into the air. The type of fuel depends on the type of lantern/lamp, it might be liquid or gas. In use, fuel is burned inside the mantle-the heating of the latter causes the thorium to emit an incandescent glow. The fabric of a hard mantle is supported by a metal frame that gives it a dome-like shape. The soft mantle is essentially a bag with either a drawstring or some type of fitting that attaches the mantle to the burner. Lastly, it is coated with lacquer and fashioned into one of two types of mantles: a soft mantle or a hard mantle. The fabric is then removed from the solution and dried. For example, cerium is added to increase the light output, while beryllium increases the mantle’s strength. Other metals are added to the solution for a variety of reasons. The mantles are produced by dipping a meshed fabric (e.g., nylon web) into a solution of thorium nitrate.

Some are used in outdoor light fixtures, and some are used indoors, especially in vacation cabins.

#Coleman mantles portable#

Today, these mantles are generally used in portable lanterns for camping. This has been replaced with the part numbers you posted.The thorium-containing incandescent mantle was invented in 1884 by Carl Auer von Welsbach, an Austrian chemist, and it is sometimes referred to as a “Welsbach mantle” or “Auerlicht.” This invention resulted in the first commercial use of the element thorium. I don't think you can buy #21A mantles anymore, the only actual 21A mantles I have seen are vintage and I am pretty sure they contained thorium and they do not make them anymore. No, I am pointing out that the mantles you posted pictures of are #21, just as is tprinted on the package. So are you saying that there are #21 and #21A mantles ie they are for two types of lanterns? Just like my Coleman #51 mantle package is marked 51A104ĮTA: I believe the coleman 21A mantles were also marked silk-lite and contained thorium. The photos you posted are marked the same. I have packs of both those mantles and the 2-pack is labelled 21A10 2 and the 4-pack is 21A10 4Īnd both packs are listed as #21 mantles. Unfortunately, stores around here only carry one type. So I need to make sure I have extras for all of them. In 1952, approximately 65 of the thorium produced in the U.S. It would be nice if I had it all standardized, but I have 4 types of Coleman lanterns: #20, #21, Northstar and #11 kerosene lanterns.