The sima hall is used for meditation, and it is huge, two stories, each story about half of the size of a football field. People sit in a grid pattern facing forward toward the altar, on each floor. There would be plenty of room for 1000 meditators.
The meditation periods are long: one and a half hours. I found that this was manageable by shifting from left foot forward to right foot forward then back again during the period. The Burmese monks sit often in positions that are inconceivable in Zen, but the standard cross-legged position is ... (you guessed it) the Burmese position; no one sits half or full lotus, except for foreign monks. The monks are very diligent in their practice. Many of them sit in the afternoon right through the walking meditation period, so from 1 – 5pm, four hours, often without moving. PAT is the sittingest place I've every been. Of course they're professionals: they're monks! Very inspiring. The Burmese claim to have produced a few arahants in the last century, and it is easy to imagine that this could well be true. Most of the monks at PAT are working with teachers of the Pa Auk Tawya method, which is basically that of Buddhaghosa in the Path of Purification (6th century AD), with particular emphasis on concentration prior to vipassana.
Once when I was meditation the thought came into my head of Western teachers that facilitate no-effort enlightenment experiences in a pleasant seminar context, and what the Burmese monks would think of that. I imagined the hundreds of them having enlightenment experiences like popcorn, but thinking that this is a pretty frivolous way to spend the time.
Meditation hardware is sparse at PAT: Everyone has a 2' x 2' x 1/2" piece of foam plastic to sit on, on top of a hardwood floor. About half of the monks just lay their bowing cloths over that. Sitting cushions are available; they are rectangular, about 2" high and stuffed with straw. Most are pretty dilapidated. There are a few thinner cushions and people like me use towels are whatever they need for knees. There are no chairs or special arrangements at all; everybody is on the floor.
One of the things that we probably need to reconsider in the West is the advisability of forcing people into Eastern sitting postures. We really are a chair culture. Burmese, as Japanese, grow up on the floor, and sit completely comfortably there. They have a wider range of postures they can assume. In Burma squatting is considered almost the most comfortable posture; they do it with both fleet flat on the ground, which is beyond my capability. In the West people are often advised to sit through the pain, a practice whose benefits are less available to Easterners, then we end up injuring ourselves. On the other hand there is something very grounded about sitting on the floor.
Once when I was meditation the thought came into my head of Western high-tech multi-layered, adjustable meditation cushions, and how the simple monks at Pa Auk Tawya would react to such consumer products.
There were a number f Mahayana monks at Pa Auk Taya, mostly Korean and Chinese. This was interesting for me because they look more like I looked a couple of months earlier. Most of the Mahayana monks observe almost the same precepts as the Theravada monks, and an additional set to boot. But their attire and style is quite a bit different, reflecting the development of the school over many centuries in the Chinese cultural area. They have robes for formal occasions, but generally wear monastic work cloths (in Japan this would be samu-e), for instance, for meditation. I noticed also that the Mahayana monks always have a much more deliberate, and for me much more familiar from Zen, posture in meditation, very erect, generally in lotus, and sitting on a raise cushion. There is a stronger emphasis on physical deportment.