You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is Pin index of oxygen is: March 2005 and explain in detail?
Ans. C: 2, 5 A gas-specific pin-index system is provided on small cylinders: pins on the yoke of the anaesthetic machine mate with holes drilled in specific positions on the valve of the cylinder to provide a mechanical means of preventing incorrect connection. Index positions: Oxygen 2 and 5 Nitrous oxide 3 and 5 Air 1 and 5.