That’s a new one on me but very interesting as for the past couple of years I have been fitting cameras to the mirror housing on 8 wheel tipper trucks to give a view along the nearside of the vehicle when moving forward. The same make of vehicle (leading truck manufacturer) can also be specified to be delivered from the factory having the reversing camera wired through a switch for permanent operation.
i found an interesting discussion thread on this very subject one of the guys in the know posted this message: "The relevent regualations for vehicles is Road Vehicles (Construction and Use) Regulations 1986 Regulation 109, which clearly relates to "Television Sets." I will leave the definition of a "Television Set" to others to discuss!
Under Regulation 109 of the Road Vehicles (Construction and Use) Regulations 1986, it is an offence to drive a motor vehicle on a road if the driver is in such a position as to be able to see, whether directly or by reflection, a television screen showing anything other than information: about the state of the vehicle or equipment; about the location of the vehicle and the road on which it is located; to assist the driver to see the road adjacent to the vehicle; to assist the driver to reach his destination."
the link to the full discussion is ; http://www.5ive-o.org/forum/archive/index.php/t-10687.html
Under that Regulation 109, the line:"To assist the driver to see the road adjacent to his vehicle" seems to me to sum up what a rear-view camera is all about. After all, "adjacent" covers all parts of the road, including that part immediately behind the vehicle (and, by implication, the vehicles on it). You are not supposed to do what I can do, which is to look at the CCTV camera images (garage forecourts, shop interiors, home security ) which appear on my "spare" wireless channel if I select it while driving. (I only do it when parked, honestly!) Actually, I have a wired camera on the back of my tow vehicle, plus a wireless receiver in the rear offside; the caravan camera is wired to a transmitter fitted in the offside of the front locker 5 feet from the receiver, so no connection problems, and no wireless interference over the 35 feet from camera to monitor. I can select the appropriate input on the monitor. External CCTV signals are too weak to overcome the caravan transmitter when it is switched on (remote switch, not in gas bottle locker).
Adjacent is an adjective meaning contiguous, adjoining or abutting
In geometry, adjacent is when sides meet to make an angle.
In graph theory adjacent nodes in a graph are linked by an edge.
In trigonometry the adjacent side of a right-angled triangle is the cathetus next to the angle in question.
I always believed adjacent to mean at the side, front and rear are self explanatory, when buying a house for example they will state "front and rear gardens" and "adjacent propertys" ive never heard the word used to describe the front or rear.
At the end of the day if it where legal to use these devises at all times when the vehicle was in motion then Surely the manufacturers would not waste time and money fitting disabling devices to them when fitted !.
Conversely, if it was illegal, would manufactures fit switches to allow continuous operation? I think a police officer would have to be very short sighted to report you for using a rear view camera whilst moving forward, especially as his patrol car may well be fitted with a forward facing camera and screen. I guess we won't know until the first court case.
According to the Oxford English Dictionary, the word comes from the Latin, meaning "lying near (or next) to". Its use by estate agents in describing houses is generally not going to refer to something in front or behind, because that's usually still your own property (can't imagine a house with land at sides, but nothing front and back).
I'm not sure why any installer should want to cut power to the screen when the vehicle is in motion - that's the time when you need to be sure what's in the bits your mirrors don't show! It could be that some drivers would connect a DVD player and watch a film as they drove!!