> ## Documentation Index
> Fetch the complete documentation index at: https://calcs.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Read Traffic Light Checks

> How traffic lights show whether each structural check passes, is near the limit, or fails.

**Traffic lights** are visual indicators that show whether a structural check passed, is near the limit, or failed, based on utilization. When you change inputs (for example, increase loads in the Loads section), the traffic lights update so you can see how the design is performing at a glance.

<iframe src="https://fast.wistia.com/embed/medias/8m8uh1c6br" title="Traffic lights and Member Selector" className="w-full h-96 rounded-xl" allowFullScreen allow="autoplay; fullscreen" />

<Tip>
  This video also covers the Member Selector. See [Member Selector](/docs/running-calculations/member-selector) for the written walkthrough.
</Tip>