Hazardous Area Classification

Haven't posted in a long time; this is actually my first post of this year. I want to share a link which provides a 5 minute primer on Hazardous Area Classification, a subject that many process engineers find technically challenging and confusing. This primer should help in clearing some cobwebs and stimulate further reading for a deeper understanding of the various codes and practices that are followed in the industry. There is considerable amount of theoretical understanding behind the practice of Hazardous Area Classification and I would like to see it included in undergraduate chemical engineering curricula. Industry should actively push this case to get "safety-primed" process engineers.