> 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-mastermap-highways-network-fundamentals/os-mastermap-highways-network-code-lists/namedperiodvalue.md).

# NamedPeriodValue

The NamedPeriodValue Code List is used to name specific periods when a restriction may apply. This code list is used for the property ‘namedPeriod’ within the data type DayPropertyType in OS MasterMap Highways Network – RAMI and OS MasterMap Highways Network – Paths products. The following table lists the codes which can be found.

## **Code List: NamedPeriodValue**

{% embed url="<http://www.ordnancesurvey.co.uk/xml/codelists/highways/NamedPeriod.xml>" %}

| Code                         | Description                                                                                          |
| ---------------------------- | ---------------------------------------------------------------------------------------------------- |
| Firing Times                 | A period when the activities of defence forces make it unsafe.                                       |
| Extreme Weather              | A period when weather conditions are dangerous.                                                      |
| School Holidays              | A period when schools are closed.                                                                    |
| Term Time                    | A period when schools are open.                                                                      |
| School Arrival And Departure | The time when pupils will be arriving for the start of the school day and the end of the school day. |
| School Hours                 | The period of the day when schools are open.                                                         |
| Local Times Apply            | A time which varies locally.                                                                         |
| Special Arrangements         |                                                                                                      |


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