There’s a shooter at work. What do you do?

There you are, working as you do every day. Then you hear it: Pop, pop, pop, pop, pop. Could it be gunfire? What do you do?

What once seemed extraordinary, no longer does. So far this year, authorities have reported 355 mass shootings, defined as any shooting spree in which four or more people are shot.

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Most victims found themselves unexpectedly under siege -- at work, at school, at a concert, watching a movie, at home.

The average citizen doesn’t have the benefit of military or law enforcement training to cope with violent confrontations. But experts say anyone can take steps to better prepare for what once seemed unthinkable.

“What you do as a citizen is what determines your outcome,� says personal defense trainer Angel Naves.

Naves spent 12 years in the Navy and trained SEALs in Duane Dieter’s Close Quarters Defense, or CQD. Now he trains civilians in situational awareness at Sports Academy in Thousand Oaks.

Here are some of his suggestions to give yourself a better chance of surviving an attack:

Assess your environment:

• Before there’s ever a danger, really know the places where you spend your time.
• Where do people approach from?
• Where is there access?
• How could I escape?

Be aware of what you can see -- and what you can’t. If it’s an environment you can control, try to eliminate danger -- or the opportunity for it -- before there is an issue. Try to “design [your environment] as part of your defense network.�

Whether it’s your workplace, your favorite diner or nail salon, or even your home, look around and figure out the entry and exit points. Consider who has access. Look around and figure out the areas where you could “contain a threat,� lock down, seek shelter and barricade yourself.

Always be vigilant, and trust your gut:

Have the presence of mind to notice patterns of behavior or routines -- and when those things change.

“Avoid what you perceive as developing threats and threatening persons, Naves said. “Even when you can’t see persons who could be a threat, eliminate the opportunity.�

If you hear or see something that doesn’t feel right, don’t ignore it.

When it comes to people you have regular contact with, Naves says, “you can almost always see something developing,� if trouble is brewing.

Beyond identifying problems with other people, being vigilant is key. It can be as simple as noticing someone around who shouldn’t be, or someone behaving strangely. And then do something with that information. Respond to it, report it.

Be in the moment:

Despite the precautions you may have pondered or taken, danger is here. Hurry and wrap your head around the reality, Naves urges. Some people freeze under the stress of the situation.

“Inside their head, they’re trying to process why this is happening instead of just realizing this is happening.�

Having presence of mind will help you better see, hear and assess what’s happening and how to respond.

Read the scene:

Where are you in relation to the danger?

As Naves noted, with many attacks, “usually these situations happen with such velocity ... if an assailant doesn’t have direct access, they will usually move on.�

Can you get away? Are those exits you scoped out earlier accessible?

“If you can’t guarantee that you would know where to escape and could escape safely, then don’t expose yourself,� he said.

If you find that hiding is the safest option:

• Don’t hide in plain sight.
• Conceal yourself and try to get behind other things that could give you cover.
• Barricade the room you're in with something heavy, dense and solid, such as an oak desk.
• Get low. Bullets can cut through walls and doors.
• Very few things would stop a bullet directly, but could cut down their velocity.
• Cover the most vital parts of your body: head, face and upper torso.
• Be quiet. “If they were to hear you or hear any duress, it might give your location away.â€�

“Oftentimes, people with a gun think they have all the power,� Naves said. “Even when it’s multiple assailants ... usually in the work environment, you outnumber them greatly.�

Banding with others under attack may be one of your most powerful defenses, he said. As you consider what tactics to employ, collaboration may be key.

Run first, call later:

“We have a tendency to talk about things,� to record them, to share first and process later,� Naves said. “We want to hear their voice for assurance, to let them know I love them.� And that’s natural.

But safety should come before comfort, he says. “Run first, call later. Do the thing that will protect you first, then communicate with those who can help you or relay information in a way that would not compromise your safety.�

When you do communicate, convey information that might aid you: where the assailants are, how they are armed, whether they are acting alone or with others, what they look or sound like and whether they are injured.

Even if you play through the scenarios of possible threats, there’s no telling how you might respond when facing a violent situation.

Naves shared an example:

A doctor was in the midst of an exam. He heard gunshots outside the door. Maybe he didn’t hear them or couldn’t place them in the context of the medical office. Out of curiosity, he decided to check it out. Maybe it was an exploding oxygen tank. When he opened the door, he came face-to-face with the shooter. The shooter had been looking to exact harm randomly. He became the only fatality.

“If you think you hear violence of any kind, take that initial precautionary measure,� Naves said. “You can’t afford to be wrong.�

Chat with me on Twitter: @mmaltaisla

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