Medical experts say if there's an explosion and you fear the building will collapse, look for an area that is strong, that you can hide under and might be big enough to give you an air pocket, if it collapses around you. And grab your cellphone.
"If you are injured, lay down on the ground because help will come," said Dr. Ken Mattox, a renowned trauma surgeon at Ben Taub.
Dr. Mattox helped set up the emergency medical plan for Harris County and he says many people survive injuries in a mass casualty situation by being smart. First, make sure your cell is GPS trackable.
"Let somebody know, 'I'm OK and I'm here' or 'I'm bleeding and I need help.' If you are trapped and you have a communication device, preserve the battery as much as possible," he said.
And those who aren't injured what can you do to help? Don't make those cell phone calls. If you need to communicate do it by text because all those cell phone calls jam up the system and first responders can't get through.
Trust the paramedics to take you to the hospital that can handle your injuries. Try to tell first responders who you are and who to call.
"Rest assured, especially for Houston, especially for Harris County, especially for Texas, the system of communication is as sophisticated, if not more, than any place in the world," Dr. Mattox said.
Dr. Mattox says if mass casualties occur here, Houston hospitals are coordinated with 15-20 trauma centers across Texas. It starts with a page, like the one he got Wednesday night after the explosion in West.
It turns out they didn't need to send doctors to West, but what was needed was the mobile command center and the mobile morgue. They were also asked to put 20 ambulances on standby.
There's a board that shows how full Houston hospitals are. It's updated every 15 minutes and ambulances are directed accordingly. It keeps too many patients from going to the same hospital at the same time.
After Hurricane Katrina, Dr. Mattox says Houston handled 25,000 medical visits in the Astrodome and George R. Brown Convention Center in two weeks.
"Some of Houston's finest moments have been to mobilize, communicate, not overreact and to access what do we need to do and do we need extra help," Dr. Mattox said.
We have four Level 1 trauma centers: Ben Taub, Memorial Hermann; Children's Memorial Hermann is a Level 1 pediatric trauma center, and so is Texas Children's Hospital. UTMB in Galveston is also a Level 1 trauma center. And there are more than a dozen Level 3 trauma centers.
"All of these decisions have been pre-made, what do you do if you have such and such a situation," Dr. Mattox said.
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