The terrible events that unraveled at the Boston Marathon this week could likely have been much worse had there not been trained first aiders on the scene.
Many of them were in uniform, but there were also a lot of ordinary bystanders, whose actions saved lives and limbs.
Matthew Smith is one of those bystanders, whose actions Monday most certainly saved the life of Sydney Corcoran, a senior in high school who was severely injured at the finish line.
Smith was with some friends, and had just attended a Red Sox game.
He was walking toward Boylston Street, when, "We heard a big noise but didn't think an explosion, then a few seconds and the second one went off. People started screaming and running and chaos kicked in."
Smith said something inside him kicked in too, and he ran toward the scene of where the explosions had just happened.
Sydney Corcoran was the first person he saw, lying injured on the ground.
A bystander was trying a T-shirt around her leg, and told Smith to hold the bandage to maintain pressure.
"She was squeezing my hand and I was just trying to keep her calm; she said her head hurt so I put a shirt under her head," said Smith to CBSNews.com.
Smith said he has no formal first aid training, but, "I knew to hold her leg together and keep her leg together ... she kept asking if she was OK and I just kept squeezing her hand tighter and tighter. Her eyes were open, she was very white in the face and very quiet but squeezed my hand as tight as she could," said Smith.
He kept holding her hand, and her leg, until Sydney was placed into an ambulance.
A situation like Monday's can unfortunately never be predicted, but there are certain steps, such as learning first aid, that most individuals can take in order to protect and prepare themselves and their families for the unexpected, and the unimaginable.
Jim Judge, a member of the American Red Cross Scientific Advisory Council, said to CBSNews.com, "You're not going to send your kid out in the cold in a T-shirt and shorts, you prepare them for that weather; we have to think bigger."
Judge warns that, "In a situation like [Hurricane] Katrina or Sandy, local officials are going to be impacted just like everyone else. So we [The Red Cross] try to have people prepared for up to 72 hours. The longer you are prepared for, the better, to care of your family."
In terms of being prepared, "Water is at the top of list. One gallon per person per day, and at least a three day supply," said Judge.
"Food would be next most important thing - canned food, tuna, green beans. Make sure to have a non-electric can opener too. Peanut butter and jelly on crackers, honey and oats, granola bars, canned chicken, things with a good shelf life," said Judge, "Next, you want to stay inform - ahead and during."
In order to do this, Judge recommends hand crank radios, and flashlights, "If you have things stored, don't keep batteries in the equipment. Keep them separate until you need them so you don't destroy your equipment."
He says having a communication plan in place is the most important thing in an emergency. Judge and his family live in Florida, but the number they communicate to in the event of an emergency is based in another state.
"My family and I have a communications plan which is my brother in Chicago - we have my brother's home phone and cell phone so we can each call my brother in Chicago if we get separated ... the most important thing is letting my brother know we're ok. He's out of the impact zone," said Judge.
Another thing Judge recommends is not relying on your cell phone. "I don't remember anyone's numbers ... you get dependent on technology and now, 'what do I do cause it's in my phone that's not working'," said Judge.
"There's nothing like getting a good first aid and getting trained - just like in Boston, now you become a rescuer. You do something to save someone life ... as a Red Cross trained rescuer, you're ready to go to work," said Judge.
Amy Gross, the owner of Little Hearts CPR in New York City, teaches a first aid class several times a week.
Although her classes primarily focus on child and infant CPR, she says, "At the end of any class, when I have the time, I always say, 'OK, let's focus on adult CPR too since I have you.' You're more likely to give CPR to adults. Most people aren't going to cancel a dinner to take an adult CPR class but since I have them, I think everyone should know."
Gross also says she gets many clients who don't even know their babysitter's last name, "At a displaced person's camp, if you have to page somebody, you have to know it." Like Judge, she advises keeping a list of numbers written on a piece of paper, and not solely relying on your cell phone.
Gross also says everyone should know first aid, "We tend to get pretty cavalier when they're bigger and we're not kids ourselves but it's not just for families of young kids."
Beth Crowell, a mother of a five- and seven-year-old, says Monday's events have really made her think of the safety of her children.
"It could have been any of us standing by that finish line cheering on someone we know ... we do talk about what to do if we ever get separated in a public place. But I have never discussed anything about an emergency situation such as a natural disaster or some sort of bombing or related danger, and have to say off the top of my head I would really have to think long and hard about where to begin. It's a fine line between telling them too much and scaring them," said Crowell.
And mother of four, Finley Shaw, agrees. "As a result of Monday- I think I would say in case in we get lost, let's have a meeting place. I don't want to alarm them," Shaw said to CBSNews.com
"When you don't know if your family is OK it's the worst feeling in the world," said Judge, "The most important thing people can have is to arm themselves with the knowledge of what to do."
The Red Cross advises making the following lists:
Create an Emergency Plan:
-Meet with household members to discuss the dangers of fire, severe weather, earthquakes and other emergencies.
-Explain how to respond to each.
-Find the safe spots in your home for each type of disaster.
-Discuss what to do about power outages and personal injuries.
-Draw a floor plan of your home.
-Mark two escape routes from each room.
-Show family members how to turn off the water, gas and electricity at main switches when necessary.
-Post emergency telephone numbers near telephones.
-Teach children how and when to call 911, police and fire.
-Instruct household members to turn on the radio for emergency information.
-Pick one out-of-state and one local friend or relative for family members to call if separated during a disaster (it is often easier to call out-of-state than within the affected area).
-Teach children your out-of-state contact's phone numbers.
-Pick two emergency meeting places. 1) A place near your home in case of a fire. 2) A place outside your neighborhood in case you cannot return home after a disaster.
-Take a basic first aid and CPR class.
-Keep family records in a water and fire-proof container
Prepare a Disaster Supplies Kit:
-Assemble supplies you might need in an evacuation.
-Store them in an easy-to-carry container such as a backpack or duffle bag.
-Include: A supply of water (one gallon per person per day). Store water in sealed, unbreakable containers.
-Identify the storage date and replace every six months.
-A supply of non-perishable packaged or canned food and a non-electric can opener.
-A change of clothing, rain gear and sturdy shoes.
-Blankets or sleeping bags.
-A first aid kit and prescription medications.
-An extra pair of glasses.
-A battery-powered radio, flashlight and plenty of extra batteries.
-Credit cards and cash.
-An extra set of car keys.
-A list of family physicians.
-A list of important family information; the style and serial number of medical devices such as pacemakers.
-Special items for infants, elderly or disabled family members.
Prepare an Emergency Car Kit:
-Battery powered radio, flashlight and extra batteries
-Blanket -Booster cables -Fire extinguisher (5lb.,A-B-Ctype)
-First aid kit and manual
-Bottled water and non-perishable high energy foods such as granola bars, raisins and peanut butter
-Maps, Shovel, Flares
-Tire repair kit and pump