Safety posters are still big business, in thousands of businesses throughout the world they are the first thing on view when visiting a factory. The issues at hand are also the same today, the art is lets say ……not quite as good as it used to be.
There are some easily accessible info on vintage safety posters in particular the ROSPA website and a whole host of analysis by Rennies who have also published a book on the subject.
They suit the clean lines of the mid century modernists

Moore is an artist who has made scant impact on Google, perhaps one for further research
Another prolific contributor was of course Tom Eckersley

This one always brings a smile to my face, its quite rare and I managed to get hold of a copy a couple of years back.

I’m sure we will return to this subject, in the meantime I have added a couple of French safety posters into my For Sale section