The Journal of HazMat Transportation's™ Exclusive Comments on U.S. DOT Letters of Interpretation of the Hazardous Materials Regulations

摘要

Here the questioner in essence asks if operational temperature control measures may be used to avoid having to package a solid which melts under ambient conditions in a package capable of retaining the material in a liquid state. Whether a material is classified as a "liquid" or "solid" depends on the material's state at 20C (see definitions of solid and liquid in 171.8). This temperature was chosen largely based on 20C being the standard laboratory condition under which many classification tests are carried out. Yet ambient conditions in transport vary and a material that is a solid at 20C may not be a solid under some of the ambient conditions encountered in transport. US tests in the desert showed a temperature of 55C could be obtained inside a truck van for limited periods; organic peroxide classification requirements assume a maximum temperature of 65 C and a European study reported a high of 75C in the Persian Gulf. The questioner is concerned about a product which melts between 25C and 29C - clearly a low melting point solid which may liquefy under certain ambient transport conditions.