It came into force on 1st October. You can download a guide from ACAS about it here:
Employers are no longer free to ask pre-employment health questions. Under the Equality Act 2010, any medical questions asked before a job offer is made must relate specifically to the tasks involved in carrying out the role. This is potentially good news for people who feel that disclosing information about a condition or disability may weaken their chances of getting a job.
Still in 2010, disabled people are twice as likely as the able-bodied to be unemployed. Only one in 10 tribunal claims made under the Disability Discrimination Act – which the Equality Act mostly replaces – concerns recruitment, but discrimination there isn’t less common – just harder to prove.