Hazora · Library
UN/NA 1242 · Methyldichlorosilane
UN/NA 1242 · ERG 2024 · Guide 139
- UN/NA
- 1242
- Edition
- ERG 2024
ERG 2024 lists UN/NA 1242 (Methyldichlorosilane) under Guide 139, titled “Substances - Water-Reactive (Emitting Flammable And Toxic Gases)”.
Material name
1242 on a placard, orange panel or shipping paper
It points to the ERG 2024 entry “Methyldichlorosilane” and to Guide 139. On a numbered orange panel, 1242 is the lower number (how to read an orange panel).
ERG 2024 markings for 1242
1242 is highlighted in green, so ERG 2024 Table 1 (Initial Isolation and Protective Action Distances) has an entry for it: “Methyldichlorosilane (when spilled in water)”. Hazora shows those distances in the app, not on this page. “When spilled in water” means the material produces large amounts of toxic inhalation hazard (TIH) gases when spilled in water. Table 2 (Water-Reactive Materials Which Produce Toxic Gases) lists the gas produced: HCl (hydrogen chloride). Its guide number 139 has no P.
Entries near 1242
By number (yellow pages): before 1242 come UN/NA 1237 Methyl butyrate (Guide 129); UN/NA 1238 Methyl chloroformate (Guide 155) and UN/NA 1239 Methyl chloromethyl ether (Guide 131); after it, UN/NA 1243 Methyl formate (Guide 129); UN/NA 1244 Methylhydrazine (Guide 131) and UN/NA 1245 Methyl isobutyl ketone (Guide 127).
By name (blue pages): “Methyldichlorosilane” comes after Methylcyclopentane (UN/NA 2298, Guide 128) and Methyldichloroarsine (UN/NA 1556, Guide 152) and before Methylene chloride (UN/NA 1593, Guide 160) and Methylhydrazine (UN/NA 1244, Guide 131).
Guide 139 · Library
Guide 139 covers 29 UN/NA numbers. The 12 around 1242 in the guide’s number order: UN/NA 1183 Ethyldichlorosilane; UN/NA 1295 Trichlorosilane; UN/NA 1339 Phosphorus heptasulfide, free from yellow and white phosphorus; UN/NA 1340 Phosphorus pentasulfide, free from yellow and white phosphorus; UN/NA 1341 Phosphorus sesquisulfide, free from yellow and white phosphorus; UN/NA 1343 Phosphorus trisulfide, free from yellow and white phosphorus; UN/NA 1360 Calcium phosphide; UN/NA 3125 Poisonous solid, water-reactive, n.o.s.; UN/NA 3130 Water-reactive liquid, poisonous, n.o.s.; UN/NA 3134 Water-reactive solid, poisonous, n.o.s.; UN/NA 3385 Poisonous by inhalation liquid, water-reactive, n.o.s. (Inhalation Hazard Zone A); UN/NA 3386 Poisonous by inhalation liquid, water-reactive, n.o.s. (Inhalation Hazard Zone B).
Source: ERG 2024 (U.S. DOT PHMSA, Transport Canada, SICT Mexico), for the initial phase of a transportation incident only. Hazora is not an official ERG publication and is not affiliated with or endorsed by these or any other government agencies.