In the opening scenes Severide starts climbing the turntable ladder with an extension ladder. At the start he is not wearing a mask in the next shot he is.
On route to the factory incident, Chief Boden is immediately in front of Truck 81. We then see an internal view of Truck which pans around from Cruz driving to Casey. Boden's SUV is nowhere to be seen.
Jay's brother, Will, comes into the kitchen to pour himself a cup of coffee. Before he leaves the house, as he is holding the travel mug, he tilts his wrist to look at his watch, but does not spill any coffee.
Since it is a travel mug, it has a spill-proof lid on, hence no coffee spilled.
Since it is a travel mug, it has a spill-proof lid on, hence no coffee spilled.
As the doctor is working on severide she says to bag him. Then Brett is seen using a mask to bag him. The very next scene the doctor says he needs to be incubated but in the previous scene there was a tube already is in place.