You can find out more about occupation codes on this page.
Occupational classification codes can be used to group together jobs, roles or skill levels. Using a standard coding structure helps facilitate data analysis and makes it easier to compare data held by different Departments or organisations.
The codes exactly replicate the UK's Standard Occupational Classification 2010, which is a four tiered coding structure. There are nine major groups at the highest level and 369 unit groups at the most detailed level. The level of coding applied will depend on how much detail is needed for data analysis, but it is often useful to refer to the most detailed groups when selecting your code in any event.
The codes can be used alongside the economic (or industrial) sector codes, which are used to classify the main activity of a business or group. The occupational codes, available to download here [421kb], are used to classify individual roles.