G150's pressurised door fatally struck captain

Here is another example of where a followed SOP would have saved a life. Never leave an aircraft unattended with systems running unless a qualified person is on board that is trained in accomplishing an emergency shut down.

I have often thought a simple red light/green light pressure sensor should be visible outside and inside to warn of a differential so people don't open the door under such circumstances.

That doesn't make sense because an aircraft is normally pressurised to a pressure equivalent about 8000' agl so unless Kittila is at a higher elevation the pressure inside the aircraft should have been less than the ambient.

An unnecessary loss of life due SOP violation. Need urgent attention of the training staff to ensure non repetition of such incidents in future
May Allah bless the soul Aameen

I am curious. The objective of a pressurised cabin is to maintain the inside pressure at a level that a human can feel comfortable in. Shouldn't there be a specific pressure setting on the controls instead just pumping air into the cabin and hope someone pressed the other button to let some air out ? Even something as mundane as an air conditioner has a temperature control.