Secondary Containment

Secondary containment systems

Containment of a liquid hazardous substance is provided by the primary container, e.g. a package, a drum, a bulk tank. It is expected that in everyday storage a substance will be contained in this primary container.

 

To deal with a breach of the primary container, a secondary containment system is required. This must be designed to contain the substance, and enable the safe collection of it. The threshold quantities above which secondary containment is required depend on the hazard classification of the substance and the size of the container.

 

Secondary containment systems apply to pooling substances, that is, hazardous liquids and hazardous substances that may liquefy in a fire. By containing a spill and enabling its recovery, the secondary containment systems can prevent a potential emergency from escalating to a point where the staff at the site, the public, or the environment is at risk.

Capacity of Containment System

 

 

 

 

 

 

The capacity of secondary containments systems is specified in the Hazardous
Substances (Emergency Management) Regulations and group standards.
The following table is a summary of these.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Minimum Capacity Requirements for Secondary Containment of
Hazardous Substances that are flammable.

 

 

 

 

 

 

Container Size
Categories

Quantity - Total Pooling Potential (TPP)

 

 

 

 

 

 

Less than 5,000
litres

Greater than or equal to
5,000 litres

 

 

 

 

 

 

60 litres

At least 50%TPP

2,500 L or 25% TPP
whichever is the greater

 

 

 

 

 

 

> 60 and up to 450
litres

At least 100%TPP

5,000 L or 50% TPP
whichever is the greater

 

 

 

 

 

 

> 450 litres

At least 110% of the capacity of the largest container

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Minimum Capacity Requirements for Secondary Containment of
Classes 6, 8 and 9 that are
not also flammable.

 

 

 

 

 

 

Container Size
Categories

Quantity - Total Pooling Potential (TPP)

 

 

 

 

 

 

Less than 5,000
litres

Greater than or equal to
20,000 litres

 

 

 

 

 

 

60 litres

At least 25%TPP

5,000 L or 5% TPP
whichever is the greater

 

 

 

 

 

 

> 60 and up to 450
litres

At least 25%TPP or
110% of the largest
container whichever
is greater

5,000 L or 5% TPP
whichever is the greater

 

 

 

 

 

 

> 450 litres

At least 110% of the capacity of the largest container

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Regulation 37 of the Emergency Management Regulations 2001.
Regulation 37 (1A) as inserted by Gazette Notice #35 Shedule 7
Regulations 37 & 38 Changes to Controls.