What is the first step to take when a leak is found on a 150-pound cylinder?

When a leak is found on a 150-pound cylinder, rolling the unit until the leak is on top allows for better control and management of the situation. This action helps to prevent gas from escaping freely, as it would be contained at the top of the cylinder, thereby minimizing the risk of a hazardous situation.

In managing gas leaks, the priority is to contain the leak and prevent the spread of gas, as certain gases can pose significant safety hazards if allowed to escape. By positioning the leak at the top of the cylinder, this step can effectively reduce the potential for harmful exposure while decisions about further actions—such as shutting off valves or moving the cylinder—are made.

Taking this approach underscores the importance of safely handling pressurized gas cylinders in emergencies, which requires understanding and responding appropriately to the risks involved. The other options, while necessary in their respective contexts, do not directly address the immediate need to contain the leak before further actions can be considered.