For Kids, Home Is Where the Hazard Is : * Safety: In child-proofing their homes, parents need to crawl before they can walk in confidence, experts say.

One reason it’s important for parents to child-proof their houses with the kind of precision you might associate with a CIA headquarters is that a 2-year-old child will seize the moment you have stepped out to the porch to slam the door shut--on the day when the spare key you keep outside is, for some reason, gone.

Then this child will watch you through the glass pane with great interest. After a few minutes, though, he will tire of your wild gesticulating and wander off to do something really entertaining, like trying to interface the VCR, the garbage disposal and the downstairs toilet.

During the period between that moment and the moment when you can get back inside, a child-proof house means everything.

Even if you child-proofed the place when your first child was born, you probably missed a few things. And, as your children grow and develop new abilities, it’s important to upgrade your precautions until they no longer constitute a menace to themselves or others (usually their late 20s).

So here are a few things to cogitate on.

Get Down

Sure you need such gadgets as gates, cabinet latches and electrical outlet covers, but the best gadgets of all are your eyes and your brain. Jeanne E. Miller, president of Perfectly Safe, a child-proofing catalogue, recommends that you get down on hands and knees and spend some time at child level in your house.

You may enter a tetanus-inviting world of loose carpet tacks, upholstery staples and bent nails hanging off the undersides of tables.

If these things are anywhere to be found, promises Miller, your children will find them.

Look for things a child might choke on. Look for things a toddler might be tempted to grab in order to steady himself. Cords attached to fixtures a child might pull down on himself are a hazard. Tablecloths and toddlers are a bad combination too, says Miller.

Look under furniture for long-forgotten debris. Miller says defunct balloons and toothpicks are major sources of danger to toddlers.

Expect the Unexpected

Child-proofing, as Miller observes in her book, “The Perfectly Safe Home” (Fireside $9.95), is the science of “what if.” It’s good to have a child-proof latch on the tool shed, the garage, the reptile house. It’s even better to have thought about what would happen if your child got in there anyway.

“As parents, we can become a little bit complacent,” says Herta B. Feely, executive director of the National Safe Kids Campaign. “It’s exactly at that moment that accidents happen and injuries occur.”

If a child can climb up on a piece of furniture and lean against a window, you have a hazard, says Feely, even if the child leans against the window every day for months without incident. One day, when she leans, she’ll weigh a little more, or it will be spring and a screen will be there instead of glass.

You should not assume that your child will never do something just because she never did it before, Feely says. Likewise, you should not assume that a child is beyond the stage where you have to worry about his eating a houseplant. The child may have agreed with you that the plants are poisonous and not to be consumed, but one day six months later, a hydrangea could suddenly look good to him.

There’s No Place Like Home

Feely’s organization is making a special effort to remind parents to be vigilant during the holidays, when a lot of families travel.

If you’re planning to spend a night or two in a home or hotel room that isn’t child-proofed, you should assemble a basic kit (some socket plugs, a gate or two, a few slide locks for cabinets, some syrup of ipecac, a toilet lock).

When you arrive, you also need to acquaint your hosts with the kind of trouble your child is capable of getting into and how to avoid it. Even if your hosts are Grandma and Grandpa, they may have forgotten, during the 30 years or so since it was an issue, how easily a kid can pull a pot of hot water down off a stove or a knife down from a counter.

Feely’s organization also advises that you check the house for items that can be swallowed or that may pose choking hazards. Make sure there’s a smoke detector and an escape plan in the case of fire. If there are pets who aren’t used to children, discuss in advance how you’re going to handle that, including the possibility of offering to pay for a couple of nights in a nice kennel.

If you’re visiting grandparents, keep in mind that hauling out an old crib and some gates from the attic may be a bad idea. They may have lead paint, loose slats or a design that’s no longer considered safe.

What Are You, Nuts?

There are those who will view a zeal for child-proofing as prissiness and paranoia. After all, our parents didn’t use electrical outlet guards, and we grew up just fine, right? If all this stuff is so crucial, why hasn’t the human race been wiped out by now?

“Times have changed a lot,” says Miller. “The old days of mother being home all day are gone. Seventy-five percent of the mothers are working mothers. When they are at home, they have a lot to do.”

It may be, she says, that parents can’t watch as carefully as they used to. Also, homes have a lot more gadgets and gewgaws, many of which are hazards. Anyway, says Feely, 8,000 children 14 and younger die every year because of accidents. Another 50,000 are permanently disabled.

Feely thinks today’s parents are still badly under-informed about child safety. Accidents aren’t covered in the news the way lurid crimes are, she says, so parents tend not to realize that accidents are the No. 1 killer of children in America.

Rules of Thumb

A few stray ideas:

* In general, it’s better to have things out of reach than behind a supposedly child-proof lock or latch. You run across the occasional kid who can beat one of those devices.

* It’s also better to tell your kid that something is dangerous or potentially painful than that it’s just plain against the rules to touch. The latter just encourages the child to wait until you’re not looking. Even a 2-year-old, on the other hand, should be able to grasp “No touch. Big owwie!”

* In the category of icing on the cake are a few measures more apt to protect you and your possessions from your child. A lot of remodeled kitchens have center islands where the garbage disposal switch is on the side, within a child’s reach.

The Perfectly Safe catalogue sells switch guards. Is also sells VCR locks, which may prevent a few pinched fingers as well as keep a toddler from putting an ice cream sandwich in the Magnavox.

Get Help Child-Proofing

If you need to inform yourself on the subject of child-proofing, visit the child-care section of a good bookstore.

You should find Miller’s book and several others, including “Child Safety Is No Accident” by Jay Arena and Miriam Bachar Settle, and “The Childwise Catalog,” a consumer guide by Jack Gillis and Mary Ellen R. Fise.

Also, you can get the Perfectly Safe catalogues by calling (800) 837-KIDS.

The National Safe Kids Campaign offers printed information on child safety. Write to 111 Michigan Ave. NW, Washington, D.C. 20010-2970.