TYPES OF SEPARATOR
Separators are the big yellow tanks that you may see being delivered on a lorry. When they are installed, they are buried below ground and surrounded in concrete. Installation on-site is relatively straight forward, just needing connections to the drainage system via rocker pipes and an alarm.
At first glance there appears to be a bewildering array of different models to choose from. But to be brief, in low risk areas such as a car parks, a smaller bypass separator is required. In more risky areas such as petrol filling stations, a larger separator is required.
From these two types of separators, there are also Class 1 and Class 2. Class 1 is the higher quality, with a discharge less than 5mg/litre of oil to water ratio, and is designed for when the outfall is to a surface water drain. Class 2 is the most commonly used type, discharging to foul water drains with an oil concentration of less than 100mg/litre.
These are the basic types of separator. In addition, obviously larger hard standing areas need larger separators. And an electronic alarm also needs to be fitted.