Hazora · Library
UN/NA 2421 · Nitrogen trioxide
UN/NA 2421 · ERG 2024 · Guide 124
- UN/NA
- 2421
- Edition
- ERG 2024
ERG 2024 lists UN/NA 2421 (Nitrogen trioxide) under Guide 124, titled “Gases - Toxic and/or Corrosive - Oxidizing”.
Material name
2421 on a placard, orange panel or shipping paper
It points to the ERG 2024 entry “Nitrogen trioxide” and to Guide 124. On a numbered orange panel, 2421 is the lower number (how to read an orange panel).
ERG 2024 markings for 2421
2421 is highlighted in green, so ERG 2024 Table 1 (Initial Isolation and Protective Action Distances) has an entry for it: “Nitrogen trioxide”. Hazora shows those distances in the app, not on this page. Its guide number 124 has no P.
Entries near 2421
By number (yellow pages): before 2421 come UN/NA 2418 Sulfur tetrafluoride (Guide 125); UN/NA 2419 Bromotrifluoroethylene (Guide 116) and UN/NA 2420 Hexafluoroacetone (Guide 125); after it, UN/NA 2422 Octafluorobut-2-ene (Guide 126); UN/NA 2424 Octafluoropropane (Guide 126) and UN/NA 2426 Ammonium nitrate, liquid (hot concentrated solution) (Guide 140).
By name (blue pages): “Nitrogen trioxide” comes after Nitrogen dioxide (UN/NA 1067, Guide 124) and Nitrogen trifluoride (UN/NA 2451, Guide 122) and before Nitrogen, compressed (UN/NA 1066, Guide 120) and Nitrogen, refrigerated liquid (cryogenic liquid) (UN/NA 1977, Guide 120).
Guide 124 · Library
Guide 124 covers 15 UN/NA numbers. The 12 around 2421 in the guide’s number order: UN/NA 1045 Fluorine, compressed; UN/NA 1067 Dinitrogen tetroxide; UN/NA 1660 Nitric oxide, compressed; UN/NA 1749 Chlorine trifluoride; UN/NA 1975 Nitric oxide and dinitrogen tetroxide mixture; UN/NA 2190 Oxygen difluoride, compressed; UN/NA 2548 Chlorine pentafluoride; UN/NA 2901 Bromine chloride; UN/NA 3083 Perchloryl fluoride; UN/NA 3303 Compressed gas, poisonous, oxidizing, n.o.s.; UN/NA 3306 Compressed gas, poisonous, oxidizing, corrosive, n.o.s.; UN/NA 3307 Liquefied gas, poisonous, oxidizing, n.o.s.
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.