Class 4: Flammable solids
294 UN numbers
Class 4 covers flammable solids and other substances that can catch fire. Division 4.1 is flammable solids and self-reactive substances, 4.2 is substances that can spontaneously combust in air, and 4.3 is substances that give off flammable gas when wet.
Division 4.1: Flammable solids
Flammable solids, self-reactive substances and solid desensitized explosives.
Division 4.2: Spontaneously combustible
Substances liable to spontaneous combustion.
| UN number | Name | Hazard class | ERG guide |
|---|---|---|---|
| 1361 | Carbon, animal or vegetable originSpontaneously combustible, guide 133 | Spontaneously combustible | 133 |
| 1362 | Carbon, activatedSpontaneously combustible, guide 133 | Spontaneously combustible | 133 |
| 1363 | CopraSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 1364 | Cotton waste, oilySpontaneously combustible, guide 133 | Spontaneously combustible | 133 |
| 1365 | Cotton, wetSpontaneously combustible, guide 133 | Spontaneously combustible | 133 |
| 1366 | DiethylzincSpontaneously combustible | Spontaneously combustible | |
| 1369 | p-NitrosodimethylanilineSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 1370 | DimethylzincSpontaneously combustible | Spontaneously combustible | |
| 1372 | Fibers, animal or Fibers, vegetableSpontaneously combustible, guide 133 | Spontaneously combustible | 133 |
| 1373 | Fibers or Fabrics, animal or vegetable or Synthetic, n.o.s. with animal or vegetable oilSpontaneously combustible, guide 133 | Spontaneously combustible | 133 |
| 1374 | Fish meal, unstabilized or Fish scrap, unstabilizedSpontaneously combustible, guide 133 | Spontaneously combustible | 133 |
| 1376 | Iron oxide, spent, or Iron sponge, spent obtained from coal gas purificationSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 1378 | Metal catalyst, wetted with a visible excess of liquidSpontaneously combustible, guide 170 | Spontaneously combustible | 170 |
| 1379 | Paper, unsaturated oil treated incompletely dried (including carbon paper)Spontaneously combustible, guide 133 | Spontaneously combustible | 133 |
| 1380 | PentaboraneSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 1381 | Phosphorus, white dry or Phosphorus, white, under water or Phosphorus white, in solution or Phosphorus, yellow dry or Phosphorus, yellow, under water or Phosphorus, yellow, in solutionSpontaneously combustible, guide 136 | Spontaneously combustible | 136 |
| 1382 | Potassium sulfide, anhydrous or Potassium sulfide with less than 30 percent water of crystallizationSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 1383 | Pyrophoric metals, n.o.s. or Pyrophoric alloys, n.o.s.Spontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 1384 | Sodium dithionite or Sodium hydrosulfiteSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 1385 | Sodium sulfide, anhydrous or Sodium sulfide with less than 30 percent water of crystallizationSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 1386 | Seed cake, containing vegetable oil solvent extractions and expelled seeds, with not more than 10 percent of oil and when the amount of moisture is higher than 11 percent, with not more than 20 percent of oil and moisture combined or Seed cake with more than 1.5 percent oil and not more than 11 percent moisture. It is not to be confused with bush bread, which is also referred to as seed cake.Spontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 1387 | Wool waste, wetSpontaneously combustible, guide 133 | Spontaneously combustible | 133 |
| 1431 | Sodium methylateSpontaneously combustible, guide 138 | Spontaneously combustible | 138 |
| 1854 | Barium alloys, pyrophoricSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 1855 | Calcium, pyrophoric or Calcium alloys, pyrophoricSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 1856 | Rags, oilySpontaneously combustible, guide 133 | Spontaneously combustible | 133 |
| 1857 | Textile waste, wetSpontaneously combustible, guide 133 | Spontaneously combustible | 133 |
| 1923 | Calcium dithionite or Calcium hydrosulfiteSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 1929 | Potassium dithionite or Potassium hydrosulfiteSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 1932 | Zirconium scrapSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 2002 | Celluloid, scrapeSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 2003 | Metal alkyls, water-reactive, n.o.s. or Metal aryls, water-reactive, n.o.s.Spontaneously combustible | Spontaneously combustible | |
| 2004 | Magnesium diamideSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 2005 | Magnesium diphenylSpontaneously combustible | Spontaneously combustible | |
| 2006 | Plastics, nitrocellulose-based, self-heating, n.o.s.Spontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 2008 | Zirconium powder, drySpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 2009 | Zirconium, dry, finished sheets, strip or coiled wireSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 2210 | Maneb or Maneb preparations with not less than 60 percent manebSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 2217 | Seed cake with not more than 1.5 percent oil and not more than 11 percent moistureSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 2318 | Sodium hydrosulfide, with less than 25 percent water of crystallizationSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 2441 | Titanium trichloride, pryophoric or Titanium trichloride mixtures, pyrophoricSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 2445 | Lithium alkylsSpontaneously combustible | Spontaneously combustible | |
| 2447 | Phosphorus white, moltenSpontaneously combustible, guide 136 | Spontaneously combustible | 136 |
| 2545 | Hafnium powder, drySpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 2546 | Titanium powder, drySpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 2793 | Ferrous metal borings or Ferrous metal shavings or Ferrous metal turnings or Ferrous metal cuttings in a form liable to self-heatingSpontaneously combustible, guide 170 | Spontaneously combustible | 170 |
| 2845 | Pyrophoric liquids, organic, n.o.s.Spontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 2846 | Pyrophoric solids, organic, n.o.s.Spontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 2870 | Aluminum borohydride or Aluminum borohydride in devicesSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 2881 | Metal catalyst, drySpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 2940 | 9-Phosphabicyclonoanes or Cyclooctadiene phosphinesSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3088 | Self-heating solid, organic, n.o.s.Spontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3126 | Self-heating solid, corrosive, organic, n.o.s.Spontaneously combustible, guide 136 | Spontaneously combustible | 136 |
| 3127 | Self-heating solid, oxidizing, n.o.s.Spontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3128 | Self-heating solid, toxic, organic, n.o.s.Spontaneously combustible, guide 136 | Spontaneously combustible | 136 |
| 3174 | Titanium disulphideSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3183 | Self-heating liquid, organic, n.o.s.Spontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3184 | Self-heating liquid, toxic, organic, n.o.s.Spontaneously combustible, guide 136 | Spontaneously combustible | 136 |
| 3185 | Self-heating liquid, corrosive, organic, n.o.s.Spontaneously combustible, guide 136 | Spontaneously combustible | 136 |
| 3186 | Self-heating liquid, inorganic, n.o.s.Spontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3187 | Self-heating liquid, toxic, inorganic, n.o.s.Spontaneously combustible, guide 136 | Spontaneously combustible | 136 |
| 3188 | Self-heating liquid, corrosive, inorganic, n.o.s.Spontaneously combustible, guide 136 | Spontaneously combustible | 136 |
| 3189 | Metal powder, self-heating, n.o.s.Spontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3190 | Self-heating solid, inorganic, n.o.s.Spontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3191 | Self-heating solid, toxic, inorganic, n.o.s.Spontaneously combustible, guide 136 | Spontaneously combustible | 136 |
| 3192 | Self-heating solid, corrosive, inorganic, n.o.s.Spontaneously combustible, guide 136 | Spontaneously combustible | 136 |
| 3194 | Pyrophoric liquid, inorganic, n.o.s.Spontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3200 | Pyrophoric solid, inorganic, n.o.s.Spontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3205 | Alkaline earth metal alcoholates, n.o.s.Spontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3206 | Alkali metal alcoholates, self-heating, corrosive, n.o.s.Spontaneously combustible, guide 136 | Spontaneously combustible | 136 |
| 3254 | TributylphosphaneSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3255 | tert-Butyl hypochloriteSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3313 | Organic pigments, self-heatingSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3341 | Thiourea dioxideSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3342 | XanthatesSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3391 | Organometallic substance, solid, pyrophoricSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3392 | Organometallic substance, liquid, pyrophoricSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3393 | Organometallic substance, solid, pyrophoric, water-reactiveSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3394 | Organometallic substance, liquid, pyrophoric, water-reactiveSpontaneously combustible, guide 135 | Spontaneously combustible | 135 |
| 3400 | Organometallic substance, liquid, water-reactive, self-heatingSpontaneously combustible, guide 138 | Spontaneously combustible | 138 |
| 3497 | Krill mealSpontaneously combustible, guide 133 | Spontaneously combustible | 133 |
| 3542 | Articles containing a substance liable to spontaneous combustion, n.o.s.Spontaneously combustible, guide 135 | Spontaneously combustible | 135 |
Division 4.3: Dangerous when wet
Substances which, in contact with water, emit flammable gases.
| UN number | Name | Hazard class | ERG guide |
|---|---|---|---|
| 1183 | EthyldichlorosilaneDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 1242 | MethyldichlorosilaneDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 1295 | TrichlorosilaneDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 1340 | Phosphorus pentasulfide, free from yellow or white phosphorusDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 1360 | Calcium phosphideDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 1389 | Alkali metal amalgam, liquid or Alkali metal amalgam, solidDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1390 | Alkali metal amidesDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 1391 | Alkali metal dispersions, or Alkaline earth metal dispersionsDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1392 | Alkaline earth metal amalgamsDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1393 | Alkaline earth metal alloys, n.o.s.Dangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1394 | Aluminium carbideDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1395 | Aluminium ferrosilicon powderDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 1396 | Aluminium powder, uncoatedDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1397 | Aluminium phosphideDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 1398 | Aluminium silicon powder, uncoatedDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1400 | BariumDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1401 | CalciumDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1402 | Calcium carbideDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1403 | Calcium cyanamide with more than 0.1 percent of calcium carbideDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1404 | Calcium hydrideDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1405 | Calcium silicideDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1407 | Caesium or CesiumDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1408 | Ferrosilicon, with 30 percent or more but less than 90 percent siliconDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 1409 | Metal hydrides, water-reactive, n.o.s.Dangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1410 | Lithium aluminium hydrideDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1411 | Lithium aluminium hydride, etherealDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1413 | Lithium borohydrideDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1414 | Lithium hydrideDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1415 | LithiumDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1417 | Lithium siliconDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1418 | Magnesium, powder or Magnesium alloys, powderDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1419 | Magnesium aluminium phosphideDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 1420 | Potassium, metal alloysDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1421 | Alkali metal alloys, liquid, n.o.s.Dangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1422 | Potassium sodium alloysDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1423 | RubidiumDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1426 | Sodium borohydrideDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1427 | Sodium hydrideDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1428 | SodiumDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1432 | Sodium phosphideDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 1433 | Stannic phosphideDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 1435 | Zinc ashesDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1436 | Zinc powder or Zinc dustDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1714 | Zinc phosphideDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 1870 | Potassium borohydrideDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 1928 | Methyl magnesium bromide, in ethyl etherDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 2010 | Magnesium hydrideDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 2011 | Magnesium phosphideDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 2012 | Potassium phosphideDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 2013 | Strontium phosphideDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 2257 | PotassiumDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 2463 | Aluminum hydrideDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 2624 | Magnesium silicideDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 2805 | Lithium hydride, fused solidDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 2806 | Lithium nitrideDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 2813 | Water-reactive solid, n.o.s.Dangerous when wet, guide 138 | Dangerous when wet | 138 |
| 2830 | Lithium ferrosiliconDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 2835 | Sodium aluminum hydrideDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 2844 | Calcium manganese siliconDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 2950 | Magnesium granules, coated particle size not less than 149 micrometresDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 2965 | Boron trifluoride dimethyl etherateDangerous when wet, guide 139 | Dangerous when wet | 139 |
| 2968 | Maneb stabilized or Maneb preparations, stabilized against self-heatingDangerous when wet, guide 135 | Dangerous when wet | 135 |
| 2988 | Chlorosilanes, water-reactive, flammable, corrosive, n.o.s.Dangerous when wet, guide 139 | Dangerous when wet | 139 |
| 3078 | Cerium, turnings or gritty powderDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3129 | Water-reactive liquid, corrosive, n.o.s.Dangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3130 | Water-reactive liquid, toxic, n.o.s.Dangerous when wet, guide 139 | Dangerous when wet | 139 |
| 3131 | Water-reactive solid, corrosive, n.o.s.Dangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3132 | Water-reactive solid, flammable, n.o.s.Dangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3133 | Water-reactive solid, oxidixing, n.o.s.Dangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3134 | Water-reactive solid, toxic, n.o.s.Dangerous when wet, guide 139 | Dangerous when wet | 139 |
| 3135 | Water-reactive solid, self-heating, n.o.s.Dangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3148 | Water-reactive liquid, n.o.s.Dangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3170 | Aluminum smelting by-products or Aluminum remelting by-productsDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3208 | Metallic substance, water-reactive, n.o.s.Dangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3209 | Metallic substance, water-reactive, self-heating, n.o.s.Dangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3292 | Batteries, containing sodium or Cells, containing sodiumDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3395 | Organometallic substance, solid, water-reactiveDangerous when wet, guide 135 | Dangerous when wet | 135 |
| 3396 | Organometallic substance, solid, water-reactive, flammableDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3397 | Organometallic substance, solid, water-reactive, self-heatingDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3398 | Organometallic substance, liquid, water-reactiveDangerous when wet, guide 135 | Dangerous when wet | 135 |
| 3399 | Organometallic substance, liquid, water-reactive, flammableDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3401 | Alkali metal amalgam, solidDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3402 | Alkaline earth metal amalgam, solidDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3403 | Potassium metal alloys, solidDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3404 | Potassium sodium alloys, solidDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3476 | Fuel cell cartridges or Fuel cell cartridges contained in equipment or Fuel cell cartridges packed with equipment, containing water-reactive substancesDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3482 | Alkali metal dispersion, flammable or alkaline earth metal dispersion, flammableDangerous when wet, guide 138 | Dangerous when wet | 138 |
| 3543 | Articles containing a substance which in contact with water emits flammable gases, n.o.s.Dangerous when wet, guide 138 | Dangerous when wet | 138 |