They calm the suddenly green-haired, counsel the gray, and discourage pet owners from dying dogs to match a dress.

"We get all kinds of questions," says Clairol's consumer-services manager Jill Hee, supervisor of the company's toll-free "Call-a-Consultant" line.

"There are always a few people who want to know how they can be blond all over - we tell them our products are only recommended for use on the head. We also get people who want to bleach out dark spots on show dogs or dye a horse's tail." (Dyes are not recommended for use on animals.)

There are the hysterical calls from people whose hair has turned green because they've used the dye without reading the instructions. Or the timid calls from men who want to cover gray without anyone noticing.

But the most common question, says Hee, is about what product to use on a certain hair color to achieve a certain effect. Roughly 20,000 calls a month are answered by 19 "color-school graduates" who staff the 800 - 223-5800 line from 8:30 a.m. until 8 p.m. (EST) Monday through Friday.

The volume of calls is not surprising, considering that one of every three American women colors her hair and a majority apply their own hair dye at home, says Clairol's consumer-satisfaction director Cathi Hunt. An estimated 2 percent of American men color their hair.

"Most people's hair needs some help," says Hunt, touching her own natural-looking blond curls which she admits are dyed. "A majority of hair falls into that nondescript category between dishwater blond and paper-bag brown."

Women in metropolitan areas seem to prefer very light or very dark colors, Hunt says. An increasing number of black women are selecting lighter shades for their hair.

"The closer you stay to the way your hair naturally is, the easier it will be to take care of," she says. "For people who can take the time and can afford it, the beauty parlor is the best place to go for hair coloring."

The scare over possible cancer-causing ingredients in hair dyes apparently has not affected sales - they're up - says Hunt. Clairol, the largest hair-dye producer in the country, has removed from its products the two suspect chemicals, known as 4MMPD and 4MMPD sulfate.

"We believe they were safe," says Hunt. "We removed them because of consumer concern."

Hunt suggets the following solutions to four common hair-coloring mistakes:

1. Covering gray with a color that is too dark. "As you get older, your skin gets lighter. Gray is nature's way of compensating for this lightened skin tone. You might have had jet black hair as a child, but you're better off with a medium to light brown when you age." When you're ready to cover gray, pick a shade a little lighter than your natural color.

2. Forgetting to do a strand test and patch test. "Most people don't realize that almost everyone has hidden red in their hair. When you lighten dark hair it goes through a red stage, and some people panic at this point and wash the product off. If they had done a strand test they would have known in advance this would happen."

3. Changing too much, too fast. Try lightening your hair two steps at a time with shampoo-in, permanent hair color. If you want more, wait four to six weeks and shampoo-in another shade that is two steps lighter, and so on.

4. Coloring treated hair. A permanent, straightening or coloring may affect future coloring.