What is the maximum filling percentage for chlorine cylinders and containers by law?

The maximum filling percentage for chlorine cylinders and containers is established for safety reasons, primarily to prevent overpressure and potential hazards associated with the storage and transportation of chlorine gas. The correct answer indicates that containers should not be filled to more than 80% of their capacity. This allowance is critical because chlorine gas expands significantly with temperature changes, and maintaining this limit helps to ensure that there is adequate space in the cylinder for gas expansion, thus preventing ruptures or leaks that could pose serious risks to human health and the environment.

Larger filling percentages could lead to dangerous situations, particularly in cases of temperature fluctuation, where an increase in temperature might cause the gas to expand beyond the cylinder's safe operating limits. Therefore, the 80% limit emphasizes safety and regulatory compliance in the handling of hazardous materials like chlorine.