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Everything happens somewhere


Addresses are a core and crucial element in government data. From planning applications dealt with by local authorities, 999 response calls by the emergency services, benefit and pension payments by DWP, vehicle tax by DVLA and through to the issuing of passports by the passport office, everything happens somewhere.

Government has already recognised that in a digital age a standard address format is mandatory to streamline services, reduce duplication, drive down costs and facilitate the exchange of government data for service efficiency.

Being able to unambiguously identify locations across multiple datasets is key to promoting interoperability and reuse. And data consistency is vital for running local, regional and national services.

Recognising this, local government was a key participant in developing BS7666; Spatial datasets for geographic referencing.  BS7666 is an address standard that specifies a standard format for holding details on every property and street including a unique address identifier. 

A standard approach

The standard does not differentiate between commercial or residential properties, between occupied, developed or vacant land, between urban or rural or between addressable properties and non-addressable entities such as communications masts.

As far as properties are concerned, the standard is based on the concept of a land parcel unit known as a Basic Land and Property Unit (BLPU). A BLPU is defined in BS7666 part 2 as a contiguous area of land in uniform property rights or, in the absence of such ownership evidence or where required for administration purposes, inferred from physical features, occupation or use.

Each BLPU has a unique reference number (UPRN), a spatial reference (grid co-ordinate) and one or more Land and Property Identifiers (LPI). The LPI is basically the address of the BLPU in a standard format that uniquely identifies the BLPU in relation to a street as defined and held in the National Street Gazetteer (NSG).

The principal components of the LPI are the UPRN from the BLPU, the Unique Street Reference Number (USRN) from the NSG and sufficient elements from the hierarchy of Primary and Secondary Addressable Objects (PAON and SAON) necessary to uniquely identify the BLPU.

An Addressable Object in BS7666 terms is a real world object that has a fixed location and which may be identified and referenced by means of one or more addresses. A Primary Addressable Object Name (PAON) is simply the name given to an addressable object that can be addressed without reference to another addressable object, for example a building name or street number. A Secondary Addressable Object Name (SAON) is given to any addressable object that is addressed by reference to a PAON, for example 'First Floor'. Both PAONs and SAONs are structured to hold both numeric and character data.

The National Address Gazetteer's database structure consists of attributes specified in the BS7666 (parts 0, 1, 2 and 3) documentation including metadata to allow the transfer of data to and from external organisations. The data constraints and field validation rules are outlined in the Data Transfer Format documentation, and the Data Entry Conventions provide the Authority Address Custodian with a comprehensive and consistent maintenance resource to ensure data is managed in a consistent manner across local government.

A postcode is a critical part of an address, it is included in a wide range of systems and solutions which support many government businesses. Royal Mail are responsible for allocating postcodes to addresses.  A postcode is a sorting and routing instruction to enable Royal Mail staff to efficiently and effectively deliver mail. Therefore it is an essential address element for Government, and Royal Mail's Postcode Address File (PAF) is incorporated into AddressBase®.

One of the main advantages of AddressBase and BS 7666 data model is that it supports the inclusion of multiple addresses for a single location. Each BLPU can be referenced to an approved address but may also have any number of alternative, provisional or historic addresses which will aid cross-organisation address identification. As all of these alias records are referenced back to the same UPRN, this facilitates the linking of asset and application data to the same identifier regardless of variations in the address.


Developing interoperability

Data consistency is vital for running local, regional and national services. The National Address Gazetteer is able to unambiguously identify locations across multiple datasets, thereby promoting interoperability and reuse. The UPRN acts as a ‘golden thread', linking multiple information sets about each spatial address in Great Britain. In the same way that each person has a National Insurance number or every book features an ISBN reference, a UPRN uniquely and definitively identifies every addressable location in the country.

The UPRN is already widely used by both public and private sector organisations to link multiple datasets together and to reduce errors in data exchange between each other. It already underpins business critical applications within local authorities such as collecting council tax and electoral registration. However the UPRN still has enormous potential particularly in regard to efficiency savings and the way in which local government, central government and emergency services are delivered.

From February 2015, UPRNs were made available on a royalty-free and open basis, facilitating the further release and sharing of public and private sector addressing databases.