It's a danger that could be putting you and your family at risk.

All across the country, cops say drug dealers are using some hotels and motel rooms to manufacture or "cook" methamphetamine.

According to Sergeant Jim Gerhardt, of the Thornton, Colorado police department, near Denver, “It's probably worse now than ever.”

In early 2008, police busted a meth lab at a hotel in Kentucky and at another in Orlando, just a few blocks from Sea World.

However, after drug dealers move on, the toxic chemical residue that results from cooking meth could potentially stay for years.  The chemicals are so dangerous police wear full hazmat suits when they raid a meth lab.

INSIDE EDITION’s Matt Meagher participated in a meth lab simulation conducted at the Drug Enforcement Association’s meth lab training center in Quantico, Virginia, where police officers are trained from all across the country.

The smoke was so thick INSIDE EDITION’s Matt Meagher could not see. 

DEA official, Jerry Craig tells INSIDE EDITION that he would not stay in a hotel room he knew was previously used as a meth lab unprotected.

In a recent study, the DEA and researchers from the National Jewish Hospital in Denver, actually cooked meth in a hotel that was about to be demolished.

The study found that the hotel room’s floors, walls and ceilings were all easily and quickly contaminated.  Dr. John Martyny, an associate professor at the hospital, is worried about the effects the meth will have on future guests, especially children.

So how big of a problem is it?  INSIDE EDITION tested six Denver area hotels and motels where cops had busted meth labs, some more than two years ago, and the results were disturbing.

In one test INSIDE EDITION detected meth on the headboard of one of the beds. 

Five out of the six rooms tested had traces of meth.  Three of them, including two at popular national chains, had levels above what many experts consider safe.

INSIDE EDITION also accompanied police in Colorado as they raided a different motel.  

One woman was suspected of smoking meth in her motel room and was charged with drug possession.  The arresting officer says that the room might be contaminated with meth.  “There would be residue in the ceiling, in the area around the bed, in the bedding, in the mattress…and it'll stay there,” she says.

Nobody knows the long term impact of exposure to a room contaminated with meth.  Only a handful of states have laws that require hotel owners to decontaminate a meth contaminated room to make it safe, but the EPA is working on voluntary clean-up guidelines.

INSIDE EDITION has some important tips to help you protect you and your family:

- There are rarely signs that your hotel room might have been used as a meth lab.  But experts say you should look out for unusual stains on the walls and ceiling.  They may be red or purple in color.

- Also look for burn or drip marks on the walls.

- Meth cooks often disable smoke detectors, so make sure the one in your room hasn’t been deactivated or covered with duct tape.

- Rooms that have recently been used to cook meth may have an unpleasant chemical odor.

- Many local police departments list the addresses of former meth labs online.

- If you suspect your room was used to cook meth, don’t be afraid to ask to be moved to a new room.