Idle time

What is idle time?

Idle time, sometimes referred to as waiting time, is the time lost due to work stoppages in which machines and/or employees are ready and available but cannot be productive. It should not be confused with planned or unplanned downtime. Idle time is when work can be performed but isn’t, while downtime is when work cannot be performed at all. There are two main types of idle time: Planned idle time and unplanned idle time.

Planned idle time

Planned idle time, also known as normal idle time, refers to the time when a machine operator does not use an asset for production. This can occur when the company has a temporary work stoppage. Planned idle time can be a waste of money, and resources like energy, materials, and space.

Examples:

• Machines in a production facility need to be turned off to prevent them from overheating.
• An operator is using a machine or needs to take a scheduled break.
• A maintenance technician (opens in new tab) is waiting for a part to arrive to use a machine.

Unplanned idle time

Unplanned idle time, also known as abnormal idle time, is unavoidable since it’s usually unexpected. It generally arises from things like a lack of raw materials, waiting for other machines to complete their processes, and micro stops (which occur when a machine stops working for a short period of time due to a problem). Unplanned idle time due to inefficient workflows can have several impacts on individuals and organizations including: Decreased productivity, wasted resources, and missed deadlines.

Examples:

• A part on a machine unexpectedly breaks after recent maintenance.
• Manufacturing needs to stop at a facility due to a shortage of raw materials.
• A sudden power outage at a factory causes production to stop until power is restored.

What is the idle time formula?

Idle time is the difference between the time a machine should run versus when it is. Below is the formula to calculate idle time:

The difference between scheduled productive time and actual production time is your idle time. For example, if your asset was meant to run for twelve hours but only ran for three, your idle time would be nine hours.

What causes idle time?

Below are some examples of the causes of idle time:

• Production needs to be reduced. Perhaps too much inventory is being put out in a facility and now it’s at capacity.
• An employee may not be trained sufficiently in using a machine. For example, new employees who aren’t fully trained on an asset will not know how to use it effectively until their training is complete.
• Old processes are not being updated and implemented quickly enough to improve efficiency. For example, production processes need executive approval to be updated. If that approval takes a long time, it can hold back production and cause delays.
• Personal injury or other accidents have occurred. For example, accidents have occurred in a facility or to an employee while using a specific asset. This will prompt management to take production and the assets offline to investigate.

What are the benefits of tracking idle time?

Calculating and tracking your idle time can have many benefits for the day-to-day operations of a facility. You can use idle time to:

• Make up for the lost production time. For example, suppose an asset in your facility has unexpected idle time due to lack of raw materials. In that case, you can run the asset overtime once the materials are available to compensate for the lost time.
• Improve the efficiency of your production process. For example, if you know an asset in your production has downtime due to scheduled maintenance or a repair, you can make up for this by running production on other spare machines so that no downtime occurs.

Impact of idle time on costs and productivity

Tracking idle time is important for the obvious reason that it has a large impact on production costs and overall team productivity. Idle time leads to increased costs due to inefficiencies, wasted labor hours, maintenance expenses, and missed production targets. Additionally, idle time directly reduces productivity by reducing the time available for productive work, leading to lower output levels and potential delays in project timelines.

Idle time vs. downtime

Idle time and downtime are two very different scenarios that maintenance teams often face. Idle time refers to periods when resources like equipment or employees are not actively engaged in productive work. Downtime refers to periods when operations or production are halted entirely due to issues such as equipment failure or maintenance.

What is normal idle time?

Normal idle time varies significantly across industries and businesses. Factors such as production processes, equipment reliability, workforce efficiency, and management strategies all influence what's considered normal idle time. Benchmarks and industry standards can offer some guidance, but each business may define its own acceptable levels of idle time based on its specific circumstances and goals.

What we can highlight is that 39.4% of maintenance personnel state that they dedicate a maximum of 25% of their work hours to reactive maintenance tasks. An almost equal percentage, 39.7%, reported spending the same time on preventive maintenance. This illustrates that idle time (whether planned or unplanned) is an inevitable part of the overall maintenance team's daily tasks. What's considered normal in this range would be subject to the business, maintenance teams KPIs, etc.