Surveillance cameras are normally deployed in business area where you want to safeguard your business property, cash, or valuable items. As such, cameras are installed indoor as such items are typically stored in a locked environment or in a safe.
However, there are instances where it makes more sense to place a security camera in an outdoor environment. Cameras can be placed at the car park entrance of a building, at the back door of your premise. These places are exposed to external weather conditions, so it is important that security cameras installed in these areas are taken care of to extend their life span, saving maintenance cost in the process.
Camera lens are vulnerable to dust and water vapor, as image quality will be adversely affected; whereas internal chipsets of the security camera is sensitive to heat and dust. To protect your CCTVs, the most effective method would be to cover the camera up with a good security camera housing. A security camera housing is normally made of durable materials which are able to withstand extreme weather conditions. It helps isolate the camera from the outside world, while still allowing images to be captured without degrading the video quality.
Good security camera housings does not neccessarily constitute to higher investment cost. Most branded security camera vendors would offer to sell you compatible casing at an affordable price. If your vendor does not provide housing by any means, you are still able to find cheap housing (probably USD $30 or lesser) of realiable quality.
On a side note, you would need to pay special attention to outdoor infrared security cameras as infrared rays emitted from the camera are very sensitive to reflection. If you place these cameras in a camera housing that has a piece of glass at the front end of the casing (to allow transparent shooting), then the glass may interfere with the camera’s infrared rays, which will then cause flares to appear in the captured videos when recorded in night vision mode. For such cases, you are thus advised to purchase a security camera housing without a front glass.