Steam cleaning with high pressure water/bleach jets. Possibly like this here?
Seems to require IP69, but I could be reading it wrong.
Requiring an IP rating above IP66 is likely for specialized environments. However, in the past I've seen cameras installed on ships at some fairly substantial heights. The only way to 'clean' the domes was to use a pressure washer. High-pressure water jets can sneak water into areas that natural weather commonly does not.
Another example is cameras installed on storm chasing vehicles that get direct and powerful impacts of rain from all directions, well above normal weather conditions.
These are two examples I can immediately think of where higher IP ratings may be required. Even above IP68 (IP69K?).
Application specific, chicken plants both in the killing and processing facilities
I just recently posted a query about chemical ingress based on a situation where loose Chlorine foam penetrated an IP66-rated camera and destroyed the seals. So let's add NEMA 4X (or better) to the discussion. Our final solution: Dotworkz' new BASH enclosure ... it's compact and you can even add bulletproof to the list of features!
There are numerous applications for ingress protection beyond IP66. These applications typically involve environments where the cameras are exposed to high wind, water and dust prone environments including:
> Highway and bridge monitoring
> Industrial process monitoring (including explosion protected applications)
> Ports and maritime applications
In the past this was done with dome cameras that utilized nitrogen pressurization to provide positive air pressure inside the dome to improve their resistance to ingress by water, dust and other contaminants. Unfortunately nitrogen pressurized domes are not airtight and they will thus leak a certain amount of pressure over time, just like a tire on a car. So just like a tire, you will periodically need to add nitrogen gas to these domes. Typically this is required every 6 months. There are a lot of variables (temperature, outside air pressure, etc.), so this interval can be less.
To make matters worse, these cameras are typically installed in areas that are difficult to reach, thus the cost to maintain these types of cameras tends to be quite high. Bosch offers solutions such as the MIC Ruggedized PTZ Cameras that provide IP68/NEMA 6P ingress protection without pressurization.