You should also make sure there is suitable ventilation where the gas is being stored and used, particularly at a low level. This is because LPG is heavier than air so there is a risk of asphyxiation.
The LPG Association guidance states that the storage area must
- be secured against attack from vandals
- have warning signs in place to show the hazards
- allow for cylinders to be stored in an upright position, unless labeling states otherwise
- be easily accessible
- be kept free of flammable sources and combustible materials, including vegetation
- be located away from open drains.