6.4 SOFTWARE REQUIREMENTS
The operational characteristics of the software should meet the following requirements in particular：
- self-descriptiveness of the functions implemented by means of software;
- display of user interface status;
- software protection against unauthorized use.
7 DESIGN AND INSTALLATION
7.1 DURABILITY AND RESISTANCE TO ENVIRONMENTAL CONDITIONS
Night vision equipment should withstand the environmental conditions specified in resolution A.694(17) and in the applicable IEC requirements*.
7.2 INTERFERENCE
With respect to electrical and electromagnetic interference, night vision equipment should meet the requirements of resolutions A.694(17) and A.813(19) and the applicable IEC requirements*
7.3 POWER SUPPLY
The power supply of night vision equipment should meet the requirements of resolution A.694(17) and the applicable IEC requirements*.
7.4 INSTALLATION
Full installation instructions to meet the following requirements should be included in the manual.
The controls of night vision equipment should be installed in the workstation for navigating and maneuvering. within easy reach of the navigator.
The observation distance from the monitor should not exceed 2.3 times the monitor diagonal.
The sensor of the night vision equipment should be installed in such a way that;
- the required horizontal field of view is free of obstructions;
- further within the horizontal panning area of the sensor, in the sector up to 112.° to either side. there are no obstructions with a deepest shadow bigger than 3°：
- two deepest shadows are separated by an unobstructed field of vision of at least 30°;
