| In the 1970s, the United States, along with several other countries, banned the use of CFCs as aerosol propellants. |
| By the mid-1970s, the United States government banned the use of CFCs as aerosol propellants but it resisted a total ban for all industries. |
| Of course, the scanner could only detect metals, energy sources and chemical compounds that could be combined into propellants and explosives. |
| Smokeless propellants are expensive and not often used in making fireworks. |
| When smokeless propellants were safely ensconced in society, what did they do with the.45 Colt? |
| Liquid propellants clearly have the edge over gunpowder for military applications such as this. |
