Separation Techniques for Hazardous Goods

When it comes to separating hazardous goods, various methods are employed, including the use of distance, inert materials, cut-off storage, and detached storage.

In the process of segregating hazardous chemicals, the following approaches are commonly applied:

• Employ distance or inert materials for segregation.
• Utilize cut-off or partitioned storage areas for segregation.
• Opt for detached storage to keep incompatible goods apart.
• Ensure that incompatible goods are not stored vertically above each other.

Distance or Inert Materials

Distance or inert (mutually compatible) materials are effective means of separation when hazardous goods are not prone to violent reactions. A minimum separation distance of 3m is generally suitable for most hazardous chemicals falling under packing group III.

Extra caution is needed for hazardous chemicals equivalent to those assigned to packing group II, as they may be more reactive or pose additional dangers, such as high toxicity. When dealing with goods assigned to packing group II or those with potential dangerous reactions, a recommended minimum segregation distance of 5m is advised.

'React dangerously' refers to reactions that create hazards, including violent reactions, explosions, potentially explosive product combinations, fires, rapid heat evolution, or the production of toxic vapors or gases.

Preventing Violent Reactions

For situations where violent reactions are likely, cut-off storage may be necessary, involving the storage of goods in separate areas. The HAZCHEM code can serve as an indicator of the increased likelihood of a violent reaction. The potential for a violent reaction should be assessed if the second character in the HAZCHEM code is P, S, W, or Y.

Structural elements like curbing, ramps, bunding, or depressed floor areas can be employed to impede the flow and interaction of incompatible liquids. Distances should be measured from the edge of the spills containment system.

If both incompatible goods are solids and are unlikely to melt in a fire, the minimum segregation distance can be reduced to 1m.

Distance or inert material segregation may be suitable for certain dangerous goods, such as class 3 dangerous goods, class 6.1 goods, or ordinary combustible matter (excluding combustible liquids) and oxidizing agents.

Cut-Off Storage

Cut-off storage involves creating separate rooms or compartments within a building to isolate incompatible goods. These rooms are separated by fire-rated partitions impervious to vapors and liquids, with a recommended fire resistance wall rating of at least FRL 120/120/120.

Partitioned areas are useful for materials prone to violent reactions or high burning rates, such as large stores of class 4.2 or 5.2 dangerous goods.

Detached Storage

Detached storage entails storing incompatible dangerous goods in separate buildings, a method reserved for materials with severe fire, reactivity, or health risks.

Materials labeled 'Dangerous when wet,' such as aluminum phosphide and calcium carbide, warrant such precautions. These substances react with water, emitting toxic or flammable gases, necessitating storage in buildings without water-based fire protection systems.