This is not satire. It is taken from FEMA's ready.gov web site "In Case of Nuclear Explosion" section.

Go to the basement or middle of the building. Stay away from the outer walls and roof. Try to maintain a distance of at least six feet between yourself and people who are not part of your household. If possible, wear a mask if you’re sheltering with people who are not a part of your household. Children under two years old, people who have trouble breathing, and those who are unable to remove masks on their own should not wear them.

Then, they repeat it!

Stay inside for 24 hours unless local authorities provide other instructions. Continue to practice social distancing by wearing a mask and by keeping a distance of at least six feet between yourself and people who not part of your household.

They don't have a section for "UFOs" so I guess we don't need to worry them. Can you imagine the advise they would offer for that?

Please maintain social distancing between yourself and the lizard people.