for children below the age of 3 to ride in a passenger vehicle without "security system" (which in practice means the vehicle is not equipped with any seat belts or technical systems like Isofix), whereas children between 3 and 14 years have to ride in the back seat. Sweden specify that a child or an adult shorter than 140 cm is legally forbidden to ride in a place with an active airbag in front of it. The majority of medical professionals and biomechanical engineers agree that children below the age of two years old are much safer if they travel in a rearward facing child restraint. Child safety locks and driver-controlled power window lockout controls prevent children from opening doors and windows from inside the vehicle. Infants left in cars Very young children can perish from heat or cold if left unattended in a parked car, whether deliberately or through absent-mindedness. In 2004, the U.S. NHTSA estimated 25 fatalities per year among children left in hot cars. Teenage drivers In the UK, a full driving licence can be had at age 17, and most areas in the United States will issue a full driver's license at the age of 16, and all within a range between 14 and 18. In addition to being relatively inexperienced, teen drivers are also cognitively immature, compared to adult drivers. This combination leads to a relatively high crash rate among this demographic. In some areas, new drivers' vehicles must bear a warning sign to alert other drivers that the vehicle is being driven by an inexperienced and learning driver, giving them opportunity to be more cautious and to encourage other drivers to give novices more leeway. In the U.S. New Jersey has Kyleigh's Law citing that teen drivers must have a decal on their vehicle. Some countries, such as Australia, the United States, Canada and New Zealand, have graduated levels of driver's licence, with special rules. By 2010, all US states required a graduated driver's licence for drivers under age 18. In Italy, the maximum speed and power of vehicles driven by new drivers is restricted. In Romania, the maximum speed of vehicles driven by new drivers (less than one year in experience) is 20 km/h lower than the national standard (except villages, towns and cities). Many U.S. states allow 18-year-olds to skip some requirements that younger drivers would face, which statistics show may be