Availability is exactly what it sounds like. It is a state of readiness to perform a task or operation. The term can be applied to a person, process, or piece of equipment.

OEE and Availability

The term availability is a component of OEE or overall equipment effectiveness. This is a common measure of how suited a piece of equipment is to a production process. It is calculated as a function of availability x performance x quality.

Note that availability and quality are critical to Lean operations. Obviously, when there is low inventory, machine downtime can shut down a production line.

Performance has a somewhat murkier applicability to Lean, though. It is a measure of how fast the machine can run compared to its maximum speed. In Lean operations, you don’t necessarily want a machine running full bore.

People Availability

The availability of personnel is also extremely important in Lean operations. There is little margin for error once processes are stabilized and waste is reduced. This is because with lower variation, there is less need for excess capacity to account for problems. As a result, the number of people assigned to a process is very close to the actual number of people required.

Availability can affect operations in a few ways. First, people’s time needs to be dedicated to their production process. They can’t be distracted replenishing parts, dealing with missing tools, or handling quality issues. All of those things need to be handled by other people, whether material handlers, supervisors, or floaters.

Additionally, the support team needs to be available immediately when needed. This means that when an andon cord is pulled, the response team needs to be there quickly. It also means when there is a maintenance issue, there should not be a long wait to have it dealt with.