Is there boil water available on the train

Yes, the boil water is available on all the trains to Tibet. Usually, the water is considered safe to drink when it is boiled at 100 ℃. Yet in high elevation, the water boils are a little lower temperature. Here in the Tibet train, water boils at 70℃.

https://itibettravel.com/faq-items/is-there-boil-water-available-on-the-train/