A Justice and Community Safety Directorate spokeswoman said 51,972 checks had been granted to Canberrans as of June 30, while 400 people had either been refused or given short term or conditional registrations.

The spokeswoman said "anyone older than 16 is required to be registered where they have contact with a vulnerable person, they are not exempt and are performing a regulated activity".

"Amongst a range of exemptions, children under the age of 16 are not required to be registered."

But the spokeswoman declined to state how many youth aged between 16 and 18 had their applications rejected as that information may identify the individuals and violate privacy provisions.

"However, very few people under the age of 18 have received an outcome other than general registration," she said.

But Canberran Craig Thomler said he was surprised when his 15-year-old daughter had to get a working with vulnerable people check to work a few hours a week in a local charity shop.

"As a school student herself, she is in class with other children every day, so the need to have a police check to work for a few hours in a shop seems ridiculous given the circumstances," he said.

"Even with an age requirement of 16, the majority of 16 to 18-year-olds are still at school, leading to a ridiculous situation [where] they need a check for a part-time job, but can go to school full-time with younger kids with no check whatsoever."

The JACS spokeswoman said children were a "significant group of vulnerable people. However, the background checking was broader than a traditional working with children check".

But Mr Thomler said completing the check was not an easy task as many young people did not have the required identification, which made it hard to meet the requirements of the form.

"The charity provided the forms on paper and wouldn't accept the online version as they couldn't manage them effectively with the ACT government when registering a number of people," he said.

In June, the application process was moved online with ACT Attorney-General Simon Corbell saying the electronic form would "enable applicants to fill out their details quickly".

Mr Thomler described his daughter's experience as a "ridiculously and needlessly complex process for a child to complete when stepping into their first workplace".

There is a $73 fee to lodge a working with vulnerable person check with applicants required to specify what type of activity they intend to engage in, from coaching and tuition to respite care.

Earlier this year, the principal body representing social workers described children checks in the ACT as insufficient to protect children from harm despite the territory having one of the strongest systems in Australia.

Recently retired Public Advocate ACT and board member of the Australian Association of Social Workers, Anita Phillips, warned that while the ACT was ahead of the game in conducting checks, they were not enough to protect children.

"They really only identify the high-risk individuals; those who have already been identified as somebody who has either abused children, or been involved in child pornography. And even these checks are not consistent nationally," she said.

Ms Phillips said there was a need for higher standards for child-protection, out-of-home care and foster care services in the ACT.

"We're certainly failing children in not sufficiently monitoring the [child protection] services," she said.

Ms Phillips' comments come after an Australian Institute of Health and Welfare report earlier this year revealed almost 500 children in the ACT had been, or were likely to be abused, neglected or harmed in 2012-13.