You may reproduce traffic signs free of charge and without having to seek permission, but you must reproduce them accurately and not in a misleading context (e.g. not on roadside billboards where they could mislead drivers). (ref [1])

You are free to:

• copy, publish, distribute and transmit the Information;
• adapt the Information;
• exploit the Information commercially and non-commercially for example, by combining it with other Information, or by including it in your own product or application.

You must, where you do any of the above:

• acknowledge the source of the Information in your product or application by including or linking to any attribution statement specified by the Information Provider(s) and, where possible, provide a link to this licence;
• If the Information Provider does not provide a specific attribution statement, you must use the following:

Contains public sector information licensed under the Open Government Licence v3.0.

This licence does NOT cover:

• personal data in the Information;
• Information that has not been accessed by way of publication or disclosure under information access legislation (including the Freedom of Information Acts for the UK and Scotland) by or with the consent of the Information Provider;
• departmental or public sector organisation logos, crests and the Royal Arms except where they form an integral part of a document or dataset;
• military insignia;
• third party rights the Information Provider is not authorised to license;
• other intellectual property rights, including patents, trade marks, and design rights; and
• identity documents such as the British Passport.

Consult this guide for full details.