Final answer:
The pin-indexing system is used to ensure the proper connection of gas regulators and cylinders to prevent accidents or incorrect usage.
Step-by-step explanation:
The purpose of the pin-indexing system that has been established for compressed gas cylinders is to ensure the proper connection of gas regulators and cylinders to prevent accidents or incorrect usage. The pin-indexing system consists of a series of holes and corresponding pins on the regulator and cylinder, which are designed to fit together in a specific way.
For example, in the United States, medical oxygen cylinders have a specific pin for a specific gas, so that a regulator designed for one gas cannot be attached to a cylinder containing another gas. This helps to avoid dangerous situations where the wrong gas is used for a particular application.
Overall, the pin-indexing system plays a crucial role in maintaining safety in the handling and use of compressed gas cylinders, ensuring that the right gas is used for the intended purpose.