Surrey-based children's charity the Disability Challengers has said that massive backlogs in security checks at the education watchdog Ofsted are stopping its staff working with children in schools.
The charity, which provides play centres and leisure opportunities for disabled children, says Ofsted has cleared just three of the charity's employees to work in schools over the past 18 months.
Since the beginning of 2003, the charity has sent more than 80 security applications to Ofsted but has yet to receive a response to any of them.
The charity, which has 100 staff and volunteers, is working with Surrey County Council to provide an additional 19,000 school places for disabled children, but fears that the Ofsted delays could hamper expansion plans.
Chief executive Ric Law said: "The volume of paperwork required by Ofsted is staggering - extra work caused by administrative errors and lost paperwork is a constant drain on vital resources."