What had happened was that the company had changed the use of a conventional poultry and egg unit so that it was now used for the production of eggs which were free from specified pathogens. This was the first phase in the process for the production of vaccines. For more than ten years, the council had failed to take any enforcement action regarding the change of use, which therefore became lawful.
The company then sought a certificate confirming that the land was used for an ‘industrial process’ which involved the making of an article (i.e. part of the process of making the vaccine). The council refused, arguing that the process carried out on the site in question was incidental to a process carried out on a site within a different ‘planning unit’ (i.e. elsewhere) and, for the certificate to be justified, the processes had to be carried out within the same planning unit.
The court found that the question was a simple one. Was the land used for the making of, or incidental to the making of an article – using the word ‘incidental’ in its everyday sense? If the answer to that question was in the affirmative, as was the case in this instance, the fact that part of the process might take place elsewhere was not relevant. The certificate of lawful use had therefore to be given.
The message for occupiers of land and planning authorities alike is that a failure to enforce planning controls can legitimise a use of land which contravenes planning regulations.

