Tourniquet: When and How to Use It

Written by Mary Jo DiLonardo
Medically Reviewed by Carol DerSarkissian, MD on June 23, 2025
8 min read

If you ever found yourself in an emergency where someone was bleeding uncontrollably, would you know what to do? Understanding when and how to use a tourniquet could mean the difference between life and death. 

A tourniquet is a vital tool used to stop excessive blood loss from a limb when direct pressure and other basic first aid methods are not enough. A band made of durable, flexible materials, a tourniquet is meant to be secured tightly enough around a wounded limb that the blood flow to that area is cut off. 

A tourniquet should only be used to stop uncontrolled bleeding from an arm or a leg. "It's an uncontrolled bleed if you put pressure on the bleeding site for 10 minutes and it doesn't stop, or you're putting pressure on the site and it's still bleeding despite the pressure," says Puneet Gupta, MD, a spokesperson for the American College of Emergency Physicians. 

What types of injuries require a tourniquet

Serious accidents and traumas may cause the type of injury that would require a tourniquet, such as:

  • A complete or partial amputation from a car accident or the use of farming equipment or heavy machinery
  • A blast injury from an explosion
  • A penetrative injury like a gunshot or stab wound
  • A crushed limb

Don't try to use a tourniquet if:

  • The bleeding seems minor.
  • The bleeding can be controlled with direct pressure.
  • The wound is on the torso, neck, or head. Use direct pressure in these cases.

 

You can buy several kinds of tourniquets. And when there's no other way to stop the bleeding, you can make one yourself. 

But, Gupta says, "It's always better if you have a real tourniquet." 

Commercial tourniquets

You can buy a commercial tourniquet from a medical supply store, online, and at some drugstores.

"They're small, not that expensive, and super easy to use. You can keep one in your first-aid kit," says Gupta, who is also an assistant medical director for the Los Angeles County Fire Department. "I recommend one approved by TCCC [Tactical Combat Casualty Care]." He notes that knockoffs not on TCCC's approved list can break under the pressure needed to make a tourniquet effective. 

Pneumatic vs. non-pneumatic tourniquets. In order for a tourniquet to work, it has to be extremely tight. A pneumatic tourniquet includes a device that uses air pressure to make the tourniquet as tight as it needs to be. A non-pneumatic tourniquet has to be tightened manually with the physical strength of the person applying it, typically using a rod called a windlass. 

CAT vs SOF-T tourniquets. There are two main kinds of non-pneumatic, or manual, tourniquets: a combat application tourniquet (CAT) and a special operations forces tactical tourniquet (SOFT-T). The key difference between the two is that the CAT can be applied with one hand, which means that you can put one on yourself. Comparison studies have shown that CATs have a higher success rate than SOFT-Ts and that they are faster and easier to apply. 

How to apply a tourniquet depends on the type of tourniquet you're using. You'll follow the manufacturer's instructions on the package. But these few rules of thumb are the same for all tourniquets:

  1. Call 911 first. 
  2. Wash your hands and put on sterile gloves if you have them. 
  3. Tell the person who is bleeding that you are going to apply a tourniquet. Make sure they understand that it will be uncomfortably, perhaps even painfully, tight. 
  4. Uncover the wound. If scissors are available, cut away any clothing on the limb. 
  5. Position the tourniquet 2-4 inches above the wound, between it and the heart. Don't place the tourniquet on the wound. If the wound is just below a joint, place the tourniquet above the joint. 
  6. Note the time you applied the tourniquet, preferably on the person's forehead, where first responders won't miss it. Write T= plus the time of application.
  7. If the wound is still bleeding heavily, you can apply a second tourniquet above the first, closer to the heart. 
  8. If you know how to check someone's distal pulse (the pulse in the artery closest to the wound), do that now. If you don't feel a pulse, you've cut off the blood flow from that artery correctly. 
  9. After you've applied the first tourniquet, check the person for any other wounds with uncontrolled bleeding and apply other tourniquets as needed. 
  10. When first responders arrive, tell them your patient is wearing a tourniquet and the time it was applied. 

If you are using a windlass rod tourniquet, you will:

  1. Attach the buckle or pass the end of the strap through the buckle.
  2. Pull the free end of the strap until the tourniquet is as tight as you can get it around the limb. Some tourniquets may allow you to fasten the strap back onto itself after you have pulled it as tight as possible.
  3. Twist the rod to tighten the tourniquet. 
  4. Keep twisting until the bleeding stops or until you can't twist anymore. It will hurt, but don't stop, even if the person complains of pain. 
  5. Clip the rod in place to keep it from untwisting. 

When there's no other alternative, you may have to resort to a makeshift tourniquet. 

"A makeshift tourniquet is kind of a hail Mary," Gupta says. "You're going to need to accept that it might not work." 

But first, call 911. After you've ensured that help is on the way, gather the materials you'll need. 

Materials needed for a makeshift tourniquet

  • The strongest material you can find that can be twisted – for example, a backpack strap made of webbing, a necktie, a sleeve, or a pants leg. Make sure that it's clean. Don't use a leather belt or other material that cannot be twisted. 
  • A rigid stick-like object that can be used as a windlass, a device used to twist the tourniquet – such as a wooden spoon, a broom handle (cut down), or a closed pocket knife
  • Another piece of cloth or material to secure the windlass
  • A permanent marker
  • Sterile gloves, if available

How to apply a makeshift tourniquet

  1. Wash your hands.
  2. Put on the sterile gloves.
  3. Tell the person who is bleeding that you are going to apply a tourniquet. Make sure they understand that it will be uncomfortably, perhaps even painfully, tight. 
  4. Uncover the wound. If scissors are available, cut away any clothing on the limb. 
  5. Place the clean, sturdy cloth 2-4 inches above the wound. If the wound is just below a joint, position the cloth just above the joint. 
  6. Wind the cloth around the limb and make a half-knot. If you have enough material, wind it several times around the limb to create some padding under the knot. 
  7. Place the windlass over the half-knot, and tie another half-knot around the windlass to secure it. 
  8. Turn the windlass to tighten the cloth. Keep turning until you see the bleeding stop or until blood-red blood stops flowing, and only dark-red blood trickles out more slowly. 
  9. Use the second piece of cloth to secure the windlass tightly in place so that it doesn't unwind when you release it and so that the tourniquet doesn't loosen. 
  10. If the wound is still bleeding heavily, you can apply a second tourniquet below the first one. 
  11. If you know how to check someone's distal pulse (the pulse in the artery closest to the wound), do that now. If you don't feel a pulse, you've cut off the blood flow from that artery correctly. 
  12. Using the permanent maker, write T= and the time the tourniquet was applied on your patient's forehead. 
  13. Do not remove the tourniquet. A health care professional must do this. 
  14. After you've applied the first tourniquet, check the person for any other wounds with uncontrolled bleeding and apply other tourniquets as needed. 
  15. When first responders arrive, tell them your patient is wearing a tourniquet and the time it was applied. 

A tourniquet can be left on for up to two hours. This will allow time for first responders to arrive on the scene and address the bleeding. 

  • Not making it tight enough
  • Putting it in the wrong place, such as too close to the wound, on top of the wound, or around a joint
  • Applying it somewhere other than a limb, such as the neck, torso, or head
  • Using materials that can't withstand the pressure or that cut into the skin
  • Waiting too long to apply it
  • Removing it
  • Forgetting to note the time you put it on

A tourniquet can be a lifesaving device in an emergency. It should only be used where there is uncontrolled bleeding from an arm or leg. You must apply a tourniquet extremely tightly, and it should only be removed by a health care professional.

Why can't you remove a tourniquet?

The person will start bleeding again. Once they arrive at the hospital, health care workers will remove it and stop the bleeding by other means

Should everyone carry a tourniquet? 

No one expects to need one. But there's no reason not to have one in your first-aid kit at home or in the car. 

Can a tourniquet cause a blood clot? 

It can raise the risk of a blood clot, especially when it's used after a surgery.

Should you apply a tourniquet to your head or neck?

No, tourniquets are for limbs only. 

How many times can you reuse a tourniquet?

The FDA recommends that a tourniquet only be used once. 

What happens when you leave a tourniquet on for too long?

It can cause tissue damage, nerve damage, and even limb loss. 

When should a tourniquet be removed? 

It can be removed when the injured person has been transferred to the care of a health care professional. 

Does a tourniquet always have to go above the wound?

Yes, you want it to be between the wound and the heart