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• It is required to restrict the spread of leaking material to safely contain within its periphery and to restrict the surface area of leaking material in order to reduce evaporation and for ease of fire fighting or other emergency control activity.
• If there is no dyke or bund, leaky material may come out on road, go in the plant and make more damage.
• Dyke wall should be safe, sound and leak proof.
• Its floor should have slope with a pit in corner to provide discharge valve.
• Discharge valve should only be open when the rain water or leak.
• Volume of dyke should be slightly more than the biggest tank inside.
• Wall height should be less than 2 meter.
• Steps should be provided to go inside.
• Acid proof lining to be provided when needed.
• Dyke is always required if the liquid is stored at the atmospheric or low pressure and temperature.
• For highly volatile gases or gases at high pressure, dyke is not much useful and wire fencing is provided at a safe distance. For example, methane, ethane, propane etc.
• While opening dyke discharge valve of flammable material, spark should be avoided otherwise fire can travel inside the dyke and catch the tank.
• Blast proof wall to be provided where possibility of explosion is there.
Separation Distance
• Some recommendations are available to keep minimum safe distance, known as ‘separation distance’, between two tanks or two groups of tanks and a source of ignition.
• Based on radiant heat from the burning liquid or fire spread by vapor, such distances are prescribed.
• Normally a 15 meter or 30 meter distances are suggested but based on tank capacity this distance is variable.
• In a congested area, it is difficult to maintain the distance.
