> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-downloads/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/os-downloads/products/transport-network-portfolio/os-multi-modal-routing-network/os-mrn-known-data-issues.md).

# OS MRN Known Data Issues

## Live known data issues

| Data Issue Name                                                            | Data Issue Description                                                                                                                                                                                                                                                                                                                                                                                                               |
| -------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| Modal Change Node attribution missing                                      | <p>Modal Change Points should have an os\_nodetype containing 'Modal Change' and modes, for example, 'Bus Station;Coach Station;Modal Change' or 'Railway Station;Tram Station;Modal Change'. 31 281 modal change nodes currently have a NULL os\_nodetype. As a result there are 77 018 Modal Change Links referencing nodes that are not Modal Change Points.<br><br>This issue is being investigated by our development team.</p> |
| Missing features compared to OS Transport Network Collection of the OS NGD | <p>A small number of links (<10) are not present in OS MRN, but are present in the corresponding release of the OS Transport Network Collection in the OS National Geographic Database (OS NGD).<br></p><p>This issue is being investigated by our development team.</p>                                                                                                                                                             |
| Records with unexpected vehicle restriction attribute.                     | <p>A small number of features (<100) have a max height, weight, width or length value which is not in sympathy with the corresponding OS NGD transport link.<br><br>This issue is being investigated by our development team.</p>                                                                                                                                                                                                    |
| Records with unexpected access restriction attribute.                      | <p>A small number of features (<100) have 'access', 'access:forward' or 'access:backward' attribute values which are not in sympathy with the corresponding OS NGD transport link.<br><br>This issue is being investigated by our development team.</p>                                                                                                                                                                              |

{% hint style="info" %}
To report an issue not currently listed here, please visit the ['Contact us' page on the OS website](https://www.ordnancesurvey.co.uk/contact-us/business-government/use-os-data).
{% endhint %}


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