The period straight after an incident is when people relax and get hurt.
What is still dangerous. Broken glass everywhere, including in places you will put a hand. Damaged structures. Fires that start later from damaged wiring. Gas. Water that looks fine and is not. Roads with debris and no working signals. Downed power lines, which are live until somebody says otherwise.
Wear shoes. Foot injuries from glass are the most common single injury after a blast and the most avoidable.
Check on neighbours, particularly anyone elderly, alone or with a disability. A knock on a door costs nothing and it is how people who cannot call for help are found.
Do not drive to look. Roads need to be clear for emergency vehicles, and sightseeing traffic is a genuine obstruction.
Photograph damage before you clear it if it is safe to do so: insurance, compensation schemes and, in some circumstances, investigations all rest on what things looked like before anybody tidied.