I am responsible for 300 employees as the Emergency Preparedness Officer. We are not permitted to do a drill but during our Annual Mandatory Training I Show a fine video that was produced by the NYS Homeland Security Office. It isn’t perfect but it is excellent nonetheless. I was instructed to say viewing the video was optional but I only had one person leave and he is a manager for a co-located Office. Here is a link to the vid.
https://youtu.be/CVgXH7smBCk
I should add that one of the most horrifying mass killing incidents happened in our Hometown, and instead of reporting to the Department of Labor Office where he had an appointment, he went a few doors down Front Street to the American Civic Association where the incident occurred. The heroine of the day got many people into the Boiler Room and saved their lives. Run, Hide, Fight.
I thought it was well done and very helpful.