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Methyl mercaptan
HMT 15 June 2026
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Methanethiol ( METH-ayn-THY-ol), also called methyl mercaptan, is an organosulfur compound with the chemical formula CH3SH. It is a colorless flammable gas with a distinctive putrid smell. In small amounts, it is pervasive in nature and found in certain foods, such as some nuts and cheese. It contributes to many odors, including the emissions from pulp mills, bad breath, and flatus Wikipedia
×Note: Special provisions may be very complex. The extracts are taken from 49 CFR §172.102. Please be careful with the information, as necessary, additional conditions may be applied that are not written here. Please check the original source and report bugs.
This material is poisonous by inhalation (see § 171.8 of this subchapter) in Hazard Zone C (see § 173.116(a) of this subchapter), and must be described as an inhalation hazard under the provisions of this subchapter.
Safety relief devices are not authorized on multi-unit tank car tanks. Openings for safety relief devices on multi-unit tank car tanks shall be plugged or blank flanged.
Each bulk packaging, except a tank car or a multi-unit-tank car tank, must be insulated with an insulating material so that the overall thermal conductance at 15.5 °C (60 °F) is no more than 1.5333 kilojoules per hour per square meter per degree Celsius (0.075 Btu per hour per square foot per degree Fahrenheit) temperature differential. Insulating materials must not promote corrosion to steel when wet.
When portable tank instruction T50 is indicated in Column (7) of the § 172.101 Hazardous Materials Table, the applicable liquefied compressed gas and chemical under pressure descriptions are authorized to be transported in portable tanks in accordance with the requirements of § 173.313 of this subchapter.
Stowage category “D” means the material must be stowed “on deck only” on a cargo vessel or on a passenger vessel carrying a number of passengers limited to not more than the larger of 25 passengers or one passenger per each 3 m of overall vessel length, but the material is prohibited on a passenger vessel in which the limiting number of passengers is exceeded.
Segregation chart for load, transport, and storage
This chart shows whether loading, transport, or storage with other hazard classes is permitted, prohibited, or restricted. Based on 49 CFR §177.848.
Hinweis: In der Kompatibilitätstabelle sind Stoffe der Gefahrenklasse 2.3 abhängig der Einstufung der inhalativen Giftigkeit zu berücksichtigen (Gefahrenzone A). Siehe Sonderbestimmung 1 sowie PHMSA Interpretation #09-0252.