The nature of the US economy. In the 1950s, manufacturing was the locomotive that pulled the US economy. Most people had a fairly accurate picture in their head about what happened on the assembly line because it was an icon of American might.
Most factories have some provision for "relief" or breaks. When you work in the office you can forward phone calls to your personal phone and take a walk-about almost any time. When you are doing "knowledge work" there is little penalty in efficiency if you take a few minutes to shop for new tires for your SUV in the middle of the work day.
It is not like that on the assembly line. Unless there are plans in place, your little walk-about will stop all the workers on the line because when your station stops, the line stops.
Some of the accommodations are designed and built into the line. Those accommodations are usually called "buffers". When you scratch your nose the worker down-line from you can pull work-in-progress out of the buffer between the two of you and the worker up-line has a place to put his finished work even when you are not pulling.
There are two, basic, planned kinds of "relief": Mass Relief when everybody goes on break at the same time and Tag Relief when an extra worker rotates through the stations and relieves each worker in turn. Most factories use Mass Relief.
The problem with Mass Relief, from the standpoint of social distancing, is that all of the amenities like the TV, refrigerator, microwave and so on are in the common break-room. Three times a day all forty people on that stretch of line are crammed into the common space.
Breaks are also when everybody makes the mad dash to the restrooms. Again, people crammed close together.
The reason management likes mass relief is that it requires fewer people to run the line. The reason workers like mass relief is that breaks are when they can socialize.
The stark reality is that restarting the manufacturing economy will be contingent on risk mitigation plans. One key point in that mitigation plan will be to eliminate mass relief and replace it with tag relief. That means the number of employees will increase by about 12%.
Back in the good old days, it was common to see somebody munching on a baloney sandwich while working on the assembly line. Not any more.
Toyota was the template for how the United States implemented Lean Manufacturing.
Lean Manufacturing treats assembly as a sacred act and food MUST NOT BE CONSUMED on the assembly line. The only thing that is allowed is water in unbreakable bottles with leak-proof, screw tops. The only place food is allowed is in the break-room.
Restarting factories will have to soften that rule. Tag relief is economically viable for fifteen minute breaks because one worker can provide relief for about ten workers.
Tag relief is much less viable for a traditional, half-hour lunch break because people expect lunch in a more compressed time-frame and far more workers would be required to get them off the line for the longer break in a shorter window.
That means that management will have to tolerate employees eating their lunches in places OTHER than the break-room.
To somebody outside the manufacturing environment, these seem like small changes. The catch is that when you start treating something as sacred then you have inadvertently created a religion and religions attract zealots.
It isn't all skittles-and-cream for the workers. They will have to be responsible for washing their hands before restarting work. They will also have to become more accepting of Paragraph 215 violations, that is "management doing hourly work". There will be many more times when the supervisor will be "tagging" employees so they can hit the can because absenteeism will be horrendous. No longer will employees be encouraged to come into work when they have a minor case of the sniffles.