Joining the new child protection vetting register will be compulsory if the Protection of Vulnerable Groups (Scotland) Bill, published this week, becomes law.
Currently, only people new to working with children or changing jobs need apply to Disclosure Scotland, which can require applicants to undergo fingerprint identification.
But, under the new bill, every person working with children in Scotland will have to be on the new register by 2012.
Since Disclosure Scotland was set up in 2002, around 4,000 of the 1.5 million applicants have had to be fingerprinted.
A spokeswoman for the Scottish Executive said that, in some circumstances, the tests are needed to be 100 per cent sure of identity.
She said: "There are occasions when someone might give someone else's details when arrested, or they might have very similar details to someone on the criminal justice register."
However, the spokeswoman said secondary legislation was planned to ensure that fingerprints are destroyed once identity is confirmed.
Greg Dempster, general secretary of the Association of Headteachers and Deputes in Scotland, said the fingerprint checks might be an unwelcome necessity.
He said: "It does, on the face of it, seem heavy-handed, but if we are going to have a robust system it may well be part of it.
"There will obviously be tension and irritation for some people about being fingerprinted, but I think it probably does need to be part of it."
A spokesman for the Educational Institute of Scotland said: "It is a concern if you are making people go through the same process as if you had been arrested, just so they can do their job. It will have to be handled extremely sensitively."
Judith Gillespie, development manager of the Scottish Parent Teacher Council, warned that the vetting process would deter parents from coming forward to help.
Voluntary groups also fear that the additional cost of vetting checks could put smaller organisations out of business.
The bill requires Scottish ministers to keep a list of people banned from working with children and, for the first time, vulnerable adults.
It follows Sir Michael Bichard's report into how Soham murderer Ian Huntley was able to work at a school despite prior concerns about his suitability.