Table 3-4 Hazardous Materials Shipments by Hazard Class: 2007 and 2012
| Hazard class | Description | Value ($ billions) | Tons (millions) | Ton-miles1 | Average distance per shipment (miles) | ||||
|---|---|---|---|---|---|---|---|---|---|
| 2007 | 2012 | 2007 | 2012 | 2007 | 2012 | 2007 | 2012 | ||
| Class 1 | Explosives | 11.8 | 18.4 | 3.0 | 4.0 | 0.9 | 1.0 | 738 | 840 |
| Class 2 | Gases | 131.8 | 125.1 | 250.5 | 164.8 | 55.3 | 33.2 | 51 | 57 |
| Class 3 | Flammable liquids | 1,170.5 | 2,016.7 | 1,752.8 | 2,203.5 | 181.6 | 204.6 | 91 | 93 |
| Class 4 | Flammable solids | 4.1 | 5.4 | 20.4 | 11.3 | 5.5 | 5.8 | 309 | 565 |
| Class 5 | Oxidizers and organic peroxides | 6.7 | 7.6 | 15.0 | 12.0 | 7.0 | 5.5 | 361 | 437 |
| Class 6 | Toxic (poison) | 21.2 | 15.2 | 11.3 | 7.6 | 5.7 | 3.6 | 467 | 513 |
| Class 7 | Radioactive materials | 20.6 | 12.3 | 0.5 | S | Z | 0.4 | S | 34 |
| Class 8 | Corrosive materials | 51.5 | 75.9 | 114.4 | 125.3 | 44.4 | 37.8 | 208 | 264 |
| Class 9 | Miscellaneous dangerous goods | 30.1 | 58.0 | 63.2 | 51.0 | 23.0 | 16.1 | 484 | 530 |
| Total | 1,448.2 | 2,334.4 | 2,231.1 | 2,580.2 | 323.5 | 307.5 | 96 | 114 | |
KEY: S = data are not published because estimate did not meet publication standards. By far, the most common reason for suppressing a cell is a high coefficient of variation (greater than 50 percent).; Z = rounds to zero.
1 Ton-miles estimates are based on estimated distances traveled along a modeled transportation network.
NOTE: Value-of-shipments estimates have not been adjusted for price changes. Numbers and percents may not add to totals due to rounding.
SOURCE: U.S. Department of Transportation, Bureau of Transportation Statistics and U.S. Department of Commerce, Census Bureau, 2012 Commodity Flow Survey, Hazardous Materials (Washington, DC: February 2015), table 2b, available at www.bts.gov/publications/commodity_flow_survey/ as of March 2016.