THE GOODS : Will You Be Safe or Sorry? : Pepper spray? Smell repellent? A stun gun? Or simple prevention techniques? Experts rate what’s best at stopping crime.

Personal protection devices--those gadgets that may make you feel safer on the street--are a bewildering array of inventions, some of which seem the stuff of low-budget adventure cartoons.

You can purchase foam dyes that turn an assailant’s skin green. “Stinky vials” make you smell disgusting to discourage attackers. Then there are the old standbys--Mace, pepper spray, stun guns and noise alarms.

The Times asked for opinions on the devices from Lt. Chris West, a crime prevention specialist with the Los Angeles Police Department, Lt. Chuck Jackson of the Los Angeles County Sheriff’s Department and Warren Clark, a former California Highway Patrol member who lectures in the criminal justice department at Cal State Long Beach.

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* Chemical Mace. A brand-name tear gas that irritates the eyes, nose and throat. The container can be clipped to a belt, purse or key ring, or carried in its own pouch. Suggested retail price is $14.95. You need training and a state certificate to purchase Mace.

“Because Mace sprays as a mist, you have to be fairly close to your attacker and there’s a danger you will come in contact with the gas,” Jackson says. “It’s effective as long as it makes contact with an assailant’s eyes or mouth.”

“We carried it in the California Highway Patrol,” Clark says. “If you handled a garden-variety combatant, it would work. If you handled someone highly intoxicated with cocaine, PCP or alcohol, you’d get them angry and probably were in for a pretty good fight.”

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* Pepper Spray. Derived from red pepper plants, this substance disables by forcing the eyes shut and restricting breathing. Acute symptoms subside within 10 to 15 minutes and usually disappear within an hour. Sold in a small can with a clip, it’s the most popular personal protection device sold at three outlets contacted by The Times. A state certificate is required for purchase. Suggested retail price is $15.95.

“One of the things we particularly like is that it has a very thin, long spray and you can stand 10 or 12 feet away from people and zap them,” West says. “You don’t have to get close. Another thing that makes pepper spray different is the liquid that carries the stuff evaporates quickly. With Mace, the residue is much more virulent and long-lasting.” Pepper spray is more effective than Mace when used on people under the influence of drugs or alcohol, police say.

Says Clark: “It’s very effective. It completely debilitates an individual. It pains them immediately and they go right down to their knees. Then with a little water, you can wash it off.”

“After training, pepper spray is simple to use whether you’re 115 pounds or 315,” Jackson says. “Point, push the button and the stream goes out. In the Sheriff’s Department, it was effective about 87% of the time.”

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* Stun Guns. These battery-operated devices can be held in one hand and deliver an electric shock when metal prongs touch an assailant. Prices start at about $40.

Says West: “You must be so close to assailants with the device, you can reach out and touch them. If you get that close, they’ll be very effective. You’ll drop (the assailant) like a hot potato.

“But surprise counts for a lot. Unless you can get straight through to them right away, (attackers) may take you down hard. If they get a good, solid grip on you, you might shock yourself. And if the person is wearing a heavy-duty leather jacket, and especially if they’re big and strong, there’s a strong chance you won’t be able to debilitate them.”

* Noise Alarms. These devices produce an ear-splitting noise designed to sound an alarm and frighten an assailant. They can be carried in a pocket or purse, attached to a belt loop or worn around the wrist. Some will not stop until deactivated by a private code. Prices start at about $17.

“The whole idea with the noise alarm is to get someone’s attention,” Jackson says. “If you’re in a mall parking lot where they could hear and come to your aid, it’s a great system. But if you’re in a subterranean garage at 9 or 10 at night all by yourself, who’s going to hear you?”

“They have limited effectiveness,” West agrees. “How much attention do you pay to car alarms? Is it better than nothing? Sure. But we don’t consider it the be-all and end-all. The better ones have a nifty little clip (that) attaches to the outside of a purse. It’s real easy to activate.”

* Foam dyes. Aiming and spraying the contents of a canister can turn an assailant’s skin a different color. The device can be carried in a pocket or purse, or clipped to a pocket or waistband. One brand, Dye Witness, sells in one store for $45.

“This is a more benign version of Mace,” West says. “It comes out in a big goopy mess. It will make a Martian out of your crook. It usually lasts a while as well. I have the same issue with it as any of these devices: Are you ready to use it? It may be difficult because there’s no required training.”

Says Clark: “I don’t think it’s going to deter a rapist that much. If an individual is bent on serious crime, there is nothing in this device (that) induces a form of pain or a deterrent.”

“Since it has no debilitating effect, you might make someone real mad at you and increase their assaultive behavior,” Jackson says. “So I don’t see this as a real good preventive device. I see it as an outstanding way of identifying and capturing a suspect.”

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* Smell Repellent. These ampuls, manufactured by KBA Inc. in Atlanta under the brand name Rapel, contain a foul-smelling fluid originally designed to help oil companies find leaks in pipes. Squeeze the ampul, and a glass bubble breaks and releases the stench on your skin, making you repulsive to attackers. The tiny device, just over an inch long and the size of a pencil, can be clipped to a bra strap. Men can wear it on underclothes or on the back of a tie. Available by mail order for $19.95 plus shipping and handling.

“I think they would be of limited use,” West says. “If somebody wants you or your money and they’re high on drugs, they’re going to take what they want. They’re not going to leave you alone just because you smell bad.”

“I don’t see any debilitating effect from this device that would drive the assailant away,” Jackson says. “The odor might cause some criminals to run away but others to get mad at you. I don’t have any personal familiarity with this device, but those are my opinions.”

Experts say no matter what product a consumer buys, good preventive techniques are most important in foiling crime.

“Our strong position is that you can avoid the vast majority of problems that you get into by employing good crime prevention techniques and thus not having to rely on these devices,” West says.

These techniques start with being alert. “The robber typically avoids people who are alert,” says USC professor Marcus Felson, a specialist in criminology.

It’s also important to appear confident. “That’s readable by people,” Jackson says. “Sometimes that’s enough to keep people from going forward with an assault.”