Can i just add these people don't just look up derelict sites it is busy industrial sites such as william blyth's etc. Most of these people are not teenagers they are men and women who have full peices of PPE on them i have read the forum on numerous occasions and they recomend you take a mask with you to cover your mouth from abesto etc. They carry camera's worth more than the average on me and you would use. They arnt thick they use floresent jackets to get around with hardly being asked. It is actually amasing how the NHS left all the electric on with the Xray machine still connected up.How peoples health records where left there.Infact if you search accrington there is a brilliant peice on black abbey st path.
If anyone is intrested in learning more here is there website
UK Urban Exploration Forums