The Department of Health, Education and Welfare announced yesterday that it is tightening up on the issuance of Social Security cards. Starting Monday, even young, native-born Americans will have to send in copies of birth or baptismal certificates, drivers' licenses or other supporting documents to prove they are entitled to a card.

Until now, anyone claiming to be under 18 could simply write in, fill out an application, and get a Social Security card a few weeks later in the mail. Although it isn't supposed to be, the card is a sort of passport to getting a job, a driver's license, credit cards and other documents that ease people's way in society.

A few years ago, Congress decided that too many illegal aliens and native-born chiselers were writing away for cards that they then used to gain work, licenses, credit cards and the like. It ordered a tightening.

The rules first went into effect for aliens and older people, but are now being extended to cover everyone. It was found that some people not entitled to cards were writing in and pretending to be native-born Americans under age 18. Now, with documentation required, it will presumably be harder to falsely obtain a card.