It's Halloween. A time for trick-or-treating, bobbing for apples, lots and lots of candy and scary creatures invading our neighborhoods.

But even witches, ghosts, goblins and vampires need to be safe.

Come dusk, Napa streets will be filled with kids. Trick-or-treaters and their parents need to be aware of situations that can turn a fun night into an unpleasant experience.

Napa Fire Capt. Sharon Quick said unattended candles have been the cause of many accidental fires.

"At Halloween, we see a lot more people using candles," she said. "If you use them inside a Jack-O-Lantern make sure the candles can't tip over. Never set candles next to your house or any other combustible material. Don't leave your house while candles are burning and make sure they are extinguished before you go to bed," Quick said.

Quick said Halloween costumes can be cumbersome and "people are wearing clothing they are not used to. Be careful if you are around candles," she said.

Napa Police Sgt. Debbie Peecook said traditionally Halloween doesn't pose a problem for law enforcement.

"How much impact Halloween will have on us usually depends on what day of the week it falls on. This year with it being on a Wednesday, we shouldn't see that many more calls for service," Peecook said.

"Weekends are a different story. There are a lot more parties. But since this year it's on a school night, most parents will want their children home at an early hour," she said.

Peecook urges trick-or-treaters to travel in groups with an adult.

"Stay in well-lit areas, never go into dark alleys. If a home appears dark, it's best not to go knock on the door. There's probably no one at home, and if there is, you most likely aren't welcome. Never go inside someone's home. If someone approaches you in a car and offers a ride, don't go -- and notify an adult."

Although candy can be dandy, it can be dangerous at Halloween time.

"There have been many cases where kids bring home candy that has been tampered with," said Peecook. "Kids should not eat any of their candy before their parents have had a chance to sort through it to make sure all wrappers are sealed and nothing looks as if it has been tampered with. If parents find any candy that looks suspicious, they should call us. We will come out, take a look at it and try to determine where it came from."

Halloween also can pose threats to pets.

"Keep candy, especially chocolate, out of reach of your pets. Chocolate is toxic for dogs. The darker the chocolate, the more toxic it is. Also, the sugar and fat in candy are very hard on animals' digestive system," said Napa veterinarian Catherine Cornejo, owner of Animal Kingdom. "I have already treated a couple of dogs for eating chocolate."

Cornejo also warns pet owners to keep their cats inside on Halloween, "especially black cats."

"There is the satanic thing about black cats and that they are bad luck. Also if they get out they can get run over by a car," she said. "I haven't treated any cats or other animals that were victims of cruelty, but I see a lot of dogs who have got into the peanut butter cups and Nestle's Crunch bars."

Cornejo advises against letting pets tag along with the trick-or-treaters.

"It's much safer if they stay home, but if you want your pet to walk with you, I suggest you put one of the glow-in-the-dark necklaces around their necks. Make sure they don't try to eat it, though," she said.

"It's not a good idea to put your pet in an environment where there are a lot of kids running around squealing. It could agitate them."

Other pet safety tips include putting pets in a room inside the house to stop them from escaping when the door is repeatedly opened for trick-or-treaters; if you dress you pet in a costume, make sure the animal can see; and don't leave them unattended around burning candles.