Some chemicals become increasingly shock-sensitive with age. A list of shock sensitive and explosive materials is provided in Appendix I . Date all containers of explosive or shock-sensitive materials upon receipt and when opened. If there is a chance of explosion, use barriers or other methods for isolating the materials or the process. Pressure is also a hazard due to the large expansion ratio from liquid to gas, causing pressure build up in containers.
Many materials become brittle at extremely low temperatures.
Brief contact with materials at extremely low temperatures can cause burns similar to thermal burns. Some of the hazards associated with cryogen's are fire, pressure, weakening of materials, and skin or eye burns upon contact with the liquid. Equipment should be kept clean, especially when working with liquid or gaseous oxygen. Mixtures of gases or fluids should be strictly controlled to prevent formation of flammable or explosive mixtures. Always wear safety glasses with side shields or goggles when handling.