UN/NA 1923 · Calcium dithionite

Material name

1923 on a placard, orange panel or shipping paper

It can stand for any of three ERG 2024 entries: “Calcium dithionite”, “Calcium hydrosulfite” and “Calcium hydrosulphite”. All use Guide 135, so the number alone is enough to find the guide. On a numbered orange panel, 1923 is the lower number (how to read an orange panel).

ERG 2024 markings for 1923

1923 is highlighted in green, so ERG 2024 Table 1 (Initial Isolation and Protective Action Distances) has an entry for it: “Calcium dithionite (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 gases produced: H2S (hydrogen sulfide) and SO2 (sulfur dioxide). Its guide number 135 has no P.

Entries near 1923

By number (yellow pages): before 1923 come UN/NA 1920 Nonanes (Guide 128); UN/NA 1921 Propyleneimine, stabilized (Guide 131P) and UN/NA 1922 Pyrrolidine (Guide 132); after it, UN/NA 1928 Methyl magnesium bromide in ethyl ether (Guide 138); UN/NA 1929 Potassium dithionite (Guide 135) and UN/NA 1931 Zinc dithionite (Guide 171).

By name (blue pages): “Calcium dithionite” comes after Calcium cyanamide, with more than 0.1% calcium carbide (UN/NA 1403, Guide 138) and Calcium cyanide (UN/NA 1575, Guide 157) and before Calcium hydride (UN/NA 1404, Guide 138) and Calcium hypochlorite mixture, dry, corrosive, with more than 10% but not more than 39% available chlorine (UN/NA 3486, Guide 140).

By name (blue pages): “Calcium hydrosulfite” comes after Calcium cyanide (UN/NA 1575, Guide 157) and Calcium hydride (UN/NA 1404, Guide 138) and before Calcium hypochlorite mixture, dry, corrosive, with more than 10% but not more than 39% available chlorine (UN/NA 3486, Guide 140) and Calcium hypochlorite mixture, dry, corrosive, with more than 39% available chlorine (8.8% available oxygen) (UN/NA 3485, Guide 140).

By name (blue pages): “Calcium hydrosulphite” comes after Calcium cyanide (UN/NA 1575, Guide 157) and Calcium hydride (UN/NA 1404, Guide 138) and before Calcium hypochlorite mixture, dry, corrosive, with more than 10% but not more than 39% available chlorine (UN/NA 3486, Guide 140) and Calcium hypochlorite mixture, dry, corrosive, with more than 39% available chlorine (8.8% available oxygen) (UN/NA 3485, Guide 140).

Other names starting with “Calcium”: Calcium arsenate and calcium arsenite mixture, solid (UN/NA 1574, Guide 151); Calcium carbide (UN/NA 1402, Guide 138); Calcium chlorate (UN/NA 1452, Guide 140); Calcium chlorate, aqueous solution (UN/NA 2429, Guide 140); Calcium chlorite (UN/NA 1453, Guide 140) and Calcium hypochlorite mixture, dry, with more than 10% but not more than 39% available chlorine (UN/NA 2208, Guide 140).

Guide 135 · Library

Guide 135 covers 54 UN/NA numbers. The 12 around 1923 in the guide’s number order: UN/NA 1383 Aluminum powder, pyrophoric; UN/NA 1384 Sodium dithionite; UN/NA 1385 Sodium sulfide, anhydrous; UN/NA 1386 Seed cake, with more than 1.5% oil and not more than 11% moisture; UN/NA 1854 Barium alloys, pyrophoric; UN/NA 1855 Calcium, pyrophoric; UN/NA 1929 Potassium dithionite; UN/NA 1932 Zirconium scrap; UN/NA 2002 Celluloid, scrap; UN/NA 2004 Magnesium diamide; UN/NA 2006 Plastics, nitrocellulose-based, self-heating, n.o.s.; UN/NA 2008 Zirconium powder, dry.

Sources

• PHMSA · ERG 2024 · EN / ES / FR