What is the difference between COD and BOD?

I have received a laboratory analysis report for effluent from my sewage treatment system and am wondering what the difference between BOD and COD is?  Do I need to get both BOD and COD tested?

How do you calculate the size of a Petrol/Oil Separator needed for a site?

The last in our customer questions regarding Petrol/Oil Interceptors/Separators is; How do you calculate the size of a Petrol/Oil Separator needed for a site?

What is the difference between a Class 1 & Class 2 Separator?

We still have a few more questions to answer as regards Petrol/Oil Interceptors (Separators), next up; What is the difference between a Class 1 and Class 2 Separator?

What are the different types of Petrol/Oil Interceptor (Separator) and what is the difference between them?

Following on from last week’s question on the difference between a Petrol/Oil Interceptor & a Separator, another customer asked; What are the different types of Petrol/Oil Interceptor (Separator) and what is the difference between them?

What is the difference between a Petrol/Oil Separator and a Petrol/Oil Interceptor?

What is the difference between a Petrol/Oil Separator and a Petrol/Oil Interceptor?