Glassware under a vacuum, which poses a risk of flying glass:
- Cathode ray tubes (e.g. TVs, monitors, oscilloscopes).
- Thermionic valves / vacuum tubes (e.g. radio sets, amplifiers, rectifiers).
Vessels containing gases or liquids at greater than atmospheric pressure:
- Aerosol cans (flammable propellant gases).
- Gas cylinder bottles, valves, regulators and pipework (e.g. diving apparatus, laboratory / medical gases).
- Hydraulic systems (e.g. lifting equipment, vehicles, aircraft).
- Working steam boilers.
- Fire extinguishers.
- Heavily deteriorated tinned food where the can is bulging.
- Clockwork devices.
- Compressed springs.
Gravity can also contribute to a hazard – for instance, heavy suspended objects.