Not even a CD-Rom is three-year-old proof, as one mother discovered.
T he labours of parenthood are many, and they keep multiplying. The latest chore is supervising the use of CD-Roms.

Contrary to popular opinion, CD-Roms are not indestructible, as Joy Wharton, mother of three-year-old Tertius can attest. Left alone with Dorling Kindersley's My First Dictionary, Tertius decided it would be a good idea to bite it. The disc stopped working so Mrs Wharton inquired about a replacement.

"I contacted Dorling Kindersley and they just were not interested. They said it was like a child tearing a page out of a book. But if a page is damaged you can read the rest of the book. If a CD-Rom does not work it does not work." It took months for Mrs Wharton to get a new disc from the company.

She had better luck with Microsoft. The disc was scratched by someone (the finger of suspicion pointed at Tertius but nothing was ever proved). Mrs Wharton rang Microsoft, explained the problem and the company sent out a replacement within 24 hours.

"These titles are marketed at small children, usually aged between four and 12. They are too old to say 'Mummy, can you change the CD-Rom for me' but not old enough to do it themselves properly," says Mrs Wharton. "Companies have to accept the medium they are working in, be realistic about the market and behave accordingly. If they had asked me for pounds 10 to replace the disc, that wouldn't have been a problem."

When contacted by the Independent, Dorling Kindersley was mortified. "We only get about one call a month concerning faulty discs," says Andrew Goff, the sales and marketing director. "We send out a replacement with a reply-paid envelope for the customer to send back the damaged disc free of charge. I don't know how this can have happened."

Microsoft is not always the saint Mrs Wharton encountered. Stuart Anderson, marketing manager for support services, says in cases of genuine accident the company may replace the disc free. But its usual charge to replace a damaged CD is pounds 25 plus VAT.

Mr Anderson says people need to be more careful with CD-Roms. "The data on CD-Roms contains all sorts of clever error correction. You usually have to treat a disc really badly for it to stop working altogether. But the more dirty or scratched a disc is, the slower it will run. So put discs back in their box as soon as you have used them."

To clean a CD-Rom, wipe from the centre to the outside, not in a circular motion. Use special CD cleaners or isopropyl alcohol. A damp lint-free cloth is OK for jam and the like, but don't soak the disc. Don't leave discs in sunlight or damp conditions.