This tool is designed as an educational resource to help users estimate oxygen cylinder durations based on the NAMDET Oxygen Duration Chart. Calculations made via this estimator are based on the formula above which can be manually checked. It is not affiliated with, endorsed by, or approved by the NHS or any other healthcare organization. The estimates generated by this tool are for general guidance only and should not be relied upon as a substitute for professional clinical judgement. It remains the sole responsibility of healthcare professionals to ensure the safe and adequate provision of oxygen, including verifying that cylinders are not depleted during use.