Yes, it is safe to use 3 burner gas stoves. Most Indian houses are shifting to 3 burner stoves because of their efficiency in cooking more items less time and less energy. It is also of great advantage for joint families. They come at a reasonable cost which any Indian house can afford. There is no need to worry about safety as 3 burner stoves are tested like any other stoves, and hence it is completely safe to use them. The safety thing greatly depends on how you use the stove and how carefully you handle it.