Gasses are vital for many experiments, either as reactants or to maintain a specific environment. When purchased, gasses are stored in compressed cylinders. These cylinders have safety hazards associated with them, as do the gasses contained in them. When accepting cylinders of gas after purchase, make sure the cylinder has been hydrostatically tested within the last 5 years before accepting, and the cylinder is properly labeled with the type of gas, maximum pressure, and GHP pictogram symbols. Check MSDSs for specific gas safety precautions. When storing cylinders of compressed gas, secure them upright with a chain, cable, or strap ⅔ of the way up the cylinder to a wall or fixed bench. Do not nest cylinders. Like with other chemicals, separate and store gas cylinders based on hazard class, as seen in the table below. In addition, flammable gasses should be stored at least 20ft (6.1m) away from combustible solids or liquids.
| Gas Hazard Category | Non-Flammable | Oxidizing | Flammable | Pyrophoric | Toxic |
| Toxic | C | 20ft (6.1m) | 20ft (6.1m) | 20ft (6.1m) | – |
| Pyrophoric | C | 20ft (6.1m) | 20ft (6.1m) | – | 20ft (6.1m) |
| Flammable | C | 20 ft (6.1m) | – | 20ft (6.1m) | 20ft (6.1m) |
| Oxidizing | C | – | 20ft (6.1m) | 20ft (6.1m) | 20ft (6.1m) |
| Non-Flammable | – | C | C | C | C |
Do not store gas cylinders in areas that can exceed 125 degrees Fahrenheit (52 degrees Celsius). When storing, cylinders must have a valve protection cap. Gasses with a health hazard rating of 3 or 4 or gasses with a health hazard rating of 2 that also lack physiological warning properties (gasses lacking smell or color) should be stored in a continuously mechanically ventilated gas cabinet. Cylinders should be equipped with pressure regulators fitting to the gas contained in the cylinder and marked for maximum cylinder pressure. Gas lines and system designs should be fitted to the type of gas being used. See the CHP for specifications based on each type of gas.