Posture is key when escaping a closed Triangle Choke. Here is a series of counters to escape, based on how tight the triangle is and where your body is.

Escaping the Loosely Closed Triangle:
If your opponent has just shot the triangle (perhaps you were just in their closed guard) the first thing to do is get posture by pointing your head up, and scooting your hips forward. You should be your head and hips should be in a striagh line and perpendicular to the floor. Form this safe position, you can open the triangle by grabbing your opponents front knee or their front hip with both hands and pushing out to open.

Escaping the Tighter Triangle:
If the triangle is tighter and your head is lower and closer to their hips you’re in more danger. From here, if your opponent is pulling on your head, remove their grips off the back of your head with your free arm and then work to frame your arms. (Framing your amrs means you are sliding your trapped arm’s forearm across your opponents hips and clasping your hands and pushing down to create space. Structurally, this is like a “frame” and provides a brace for you against your opponents hips. )

To Frame:
Push the their grips off the back of your head (mentioned previously above.) Next, before they can get the grips back, hold their bicep on the side of your free arm. Pull your trapped arm across. Let go of the bicep, frame, and immediately posture.If you can frame and make distance, then go for the escape above,

If You Cannot Frame:
It’s not over yet. Push off the grip. hold their bicep. on the bicep side, reach you foot forward to pin that arm, placing your foot in their armpit. Flop onto your hip on that side. kick your other leg over as you arch back to break the triangle. Now that those feet are in your face, maybe hit a leg lock?

Survival Secrets from the Griffiths Files:
From the Triangle Master come these little known tips for survival in the face of a tight and menacing triangle. This insight has mainly to do with breathing and maintaining enough space to breath. If you’re in a really tight triangle, and your arm is flat across your neck, this trapped arm will be putting pressure on your neck, making it hard to breath. The more this arm is flexed, the more pressure it will exert on your neck. So, relax the trapped arm and turn your head to face your elbow. If you’re relaxed with your head turned, it will be very hard for the guy to finish you. From this stall position, try to get lock hands and slide your framing forearm across your opponents hops so you can start to fight for posture. Once your arms are in the proper position to push up to frame, the triangle may still be very tight. Again, try to relax the trapped arm and this time turn your head towards you trapped shoulder as you attempt to push up to frame.