There are some restrictions on installation, with cameras not being installed in an area where there is a "reasonable expectation of privacy", such as bathrooms, gym locker areas and private offices unless consent by the office occupant is given. Cameras are generally acceptable in hallways, parking lots, front offices where students, employees, and parents come and go, gymnasiums, cafeterias, supply rooms and classrooms. The installation of cameras in classrooms may be objected to by some teachers. There were an estimated 30 million surveillance cameras in the United States in 2011. Video surveillance has been common in the United States since the 1990s; for example, one manufacturer reported net earnings of $120 million in 1995. With lower cost and easier installation, sales of home security cameras increased in the early 21st century. Following the September 11 attacks, the use of video surveillance in public places became more common to deter future terrorist attacks. Under the Homeland Security Grant Program, government grants are available for cities to install surveillance camera networks. In 2009, there were an estimated 15,000 CCTV systems in Chicago, many linked to an integrated camera network. New York City's Domain Awareness System has 6,000 video surveillance cameras linked together, there are over 4,000 cameras on the subway system although nearly half of them do not work, and two thirds of large apartment and commercial buildings use video surveillance cameras. In the Washington D.

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Carbon Monoxide SensorsCarbon monoxide is a deadly gas that's odorless and colorless, so having a detector in your home can save your life.

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These real time notifications allow you to handle the situation from wherever you are – you won’t always be home when disaster strikes – and contact local emergency services if necessary.

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