In the U.S. the typical height of a "Floor" is 10 feet. He went to the 29th floor which means he had 28 beneath so 280 feet, In Thailand the standard is probably 12 feet, I'm not sure but if so that's 336 feet. I did just a little looking online about how many feet it takes for a parachute to open. The one answer I will attached below says it depends on the type of jump and the parachute. Perhaps the jumper didn't know.
It depends on what you mean by NEED to pull your chute. A BASE rig that’s packed properly and deployed properly can open pretty fast (100 feet or less). I’ve seen video of someone doing a BASE jump into a quarry filled with water from less than 100. He had just enough time to slow down before hitting the water. The guy helping him jumped in after him without a rig on and was fine. For most BASE jumping, 300 feet is the general rule of thumb, that gives you enough time for your chute to deploy and get to a safe place to land.
If you’re talking about a skydiving rig falling at terminal velocity, it takes a lot longer. I pull at 3,500 feet above ground level. People I know with a lot more experience pull at the same altitude, I’ve met some that go down as low as 2,500, but not many and everyone thinks they’re crazy. If anything goes wrong, I want time to cut away my main and pull my reserve before it’s too late. Depending on your equipment and how it’s packed, it can take around 500 - 800 feet to deploy, a hard opening will open faster, but that’s gonna hurt.
The last resort on a skydiving rig is an Automatic Activation Device (AAD). Mine is set to pull my reserve at 875 feet if I’m moving too fast. That gives me just enough time to pull my brakes and land were ever I happen to be. It’s a last effort to save your life and basically does it at the last possible second before you die.