--- title: How to use Buffer Zones for a red line description: "Airly AI allows you to check buffer zones for a red line in your assessment. Airly AI calculates four buffer zones: 20 metres, 50 metres, 100 metres, and 250 metres. Learn how to use these buffer zones effectively." --- [Skip to content](https://support.airly.org/airly/how-to-use-buffer-zones#main-content) English Show submenu for translations ![200224\_Airly\_Logo\_Lockup\_White\_RGB.png\]](https://support.airly.org/hs-fs/hubfs/200224_Airly_Logo_Lockup_White_RGB.png?height=30&name=200224_Airly_Logo_Lockup_White_RGB.png) - [Default HubSpot Blog](https://5663293.hs-sites.com/blog) Open main navigation Close main navigation - [Default HubSpot Blog](https://5663293.hs-sites.com/blog) - English Show submenu for translations Hello. How can we help you? - There are no suggestions because the search field is empty. 1. [Airly AI data management in built-in QGIS](https://support.airly.org/airly/airly-ai-data-management-in-built-in-qgis) # How to use Buffer Zones for a red line ## Airly AI allows you to check buffer zones for a red line in your assessment. Airly AI calculates four buffer zones: 20 metres, 50 metres, 100 metres, and 250 metres. Learn how to use these buffer zones effectively. Airly AI enables you to calculate and display buffer zones using two methods: 1. Upload a .shp file containing the red line boundary. 2. Create your own red line boundary in QGIS. #### Initial Buffer Zones If you upload a .shp file containing the red line, the operation is straightforward. In the **"Layers"** window, you will see that all buffer zones are available to display. **By default, each buffer zone is hidden**. You can make a particular buffer zone visible by clicking the checkbox next to it. Each buffer zone has the same red colour as the red line, but the line is thinner. ![](https://support.airly.org/hs-fs/hubfs/image-png-Jun-21-2024-12-49-01-0093-PM.png?width=688&height=452&name=image-png-Jun-21-2024-12-49-01-0093-PM.png) If a **red line is not provided** or needs to be created based on a .pdf file, **buffer zones will not be calculated initially**. #### How to display a Buffer Zone To display any buffer zone, click the checkbox near to the desired zone in the "Layers" window. For example, **to display the 50-metre buffer, find the "Site red line boundary buffer zones group", and locate the "Buffer 50m" label**. ![](https://support.airly.org/hs-fs/hubfs/image-png-Jun-21-2024-12-54-48-2889-PM.png?width=688&height=450&name=image-png-Jun-21-2024-12-54-48-2889-PM.png) To make it visible, click the checkbox next to the label. Now, you can see the buffer zone around the red line. ![](https://support.airly.org/hs-fs/hubfs/image-png-Jun-21-2024-12-55-28-8347-PM.png?width=688&height=452&name=image-png-Jun-21-2024-12-55-28-8347-PM.png) #### Buffer Zones without a Red Line If you did not provide a .shp file with a red line, buffer zones will not be available. In the "Layers" window, **only the "Site red line boundary" layer will be available**. **![](https://support.airly.org/hs-fs/hubfs/image-png-Jun-21-2024-12-44-50-1943-PM.png?width=688&height=451&name=image-png-Jun-21-2024-12-44-50-1943-PM.png)** However, you can still recalculate buffer zones and make them visible by drawing a red line. Follow the next section to learn how to do it. #### How to Recalculate Buffer Zones To recalculate buffer zones for the red line, follow these steps after making changes: **1.** Select the red line layer.  ![](https://support.airly.org/hs-fs/hubfs/image-png-Jun-21-2024-12-56-25-6734-PM.png?width=688&height=452&name=image-png-Jun-21-2024-12-56-25-6734-PM.png) **2.** Click the "Toggle Editing" icon in the top-bar menu. ![](https://support.airly.org/hs-fs/hubfs/image-png-Jun-21-2024-12-56-57-7628-PM.png?width=688&height=450&name=image-png-Jun-21-2024-12-56-57-7628-PM.png) **3.** Make any necessary changes to the red line, such as extending a feature or adding a new one. Note that **when you enter edit mode, all buffer zones will be hidden** (but they will still be visible in the "Layers" panel). ![](https://support.airly.org/hs-fs/hubfs/image-png-Jun-21-2024-12-57-33-2255-PM.png?width=688&height=451&name=image-png-Jun-21-2024-12-57-33-2255-PM.png) ![](https://support.airly.org/hs-fs/hubfs/image-png-Jun-21-2024-12-58-45-9915-PM.png?width=688&height=456&name=image-png-Jun-21-2024-12-58-45-9915-PM.png) **4.** Save changes to the layer by clicking the "Save Layer Edits" icon in the top-bar menu. ![](https://support.airly.org/hs-fs/hubfs/image-png-Jun-21-2024-12-59-03-7869-PM.png?width=688&height=454&name=image-png-Jun-21-2024-12-59-03-7869-PM.png) **5.** After saving, the buffer zones will be recalculated. To see them, you need to check the visibility of the needed buffer zone again. **Refer to the section "How to display a Buffer Zone" to review how to do this.** ![](https://support.airly.org/hs-fs/hubfs/image-png-Jun-21-2024-01-22-00-9466-PM.png?width=688&height=455&name=image-png-Jun-21-2024-01-22-00-9466-PM.png) - [FAQ](https://support.airly.org/airly/faq) - [Information about Air Quality Sensors](https://support.airly.org/airly/information-about-air-quality-sensors) - [Installation and Use of Sensors](https://support.airly.org/airly/installation-and-use-of-sensors) - [Troubleshooting](https://support.airly.org/airly/troubleshooting) - [Air Quality Indexes and Indicators](https://support.airly.org/airly/air-quality-indexes-and-indicators) - [Data and Analytics Platform (ADP)](https://support.airly.org/airly/data-and-analytics-platform-adp) - [API and Integrations](https://support.airly.org/airly/api-and-integrations) - [Airly AI assessment definition](https://support.airly.org/airly/airly-ai-assessment-definition) - [Airly AI data management in built-in QGIS](https://support.airly.org/airly/airly-ai-data-management-in-built-in-qgis) - [Airly AI ADMS files generation](https://support.airly.org/airly/airly-ai-adms-files-generation) - [Regulations and standards](https://support.airly.org/airly/regulations-and-standards) - [Default HubSpot Blog](https://5663293.hs-sites.com/blog) [![](https://support.airly.org/hs-fs/hubfs/Airly_Logo_Niebieskie_RGB.jpg?width=4168&height=1323&name=Airly_Logo_Niebieskie_RGB.jpg)](http://airly.org) Copyright © 2026, Airly sp. z o.o.