3 scenes from TV series Chernobyl that act as key reminders to doctors on safety

I recently started watching the TV series Chernobyl, chronicling the events surrounding the 1986 disaster. For anyone who hasn’t seen it yet, I’d highly recommend this excellent production (It’s already deservedly won multiple awards).
The great thing about TV like this, which documents real-life events, is that they can really bring complex consequential events to the mass audience, in a visually stimulating and educational way.
The nuclear reactor explosion that occurred at the Chernobyl plant, near the city of Pripyat in what is now Ukraine, occurred on 26 April 1986. A series of mishaps unfolded leading to the devastating explosion, releasing a plume of deadly radioactive debris into the air.
I won’t ruin the show for you by going into events in more detail, but suffice to say that a number of errors and design flaws led to the 1.23am explosion. The fallout from this occurrence was tragic, and the subject of the TV series.