Guidance

National ANPR Service technical specifications (accessible version)

Updated 14 February 2024

Version 3.4

January 2022

© Crown copyright 2020

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Definitions

Acronym Description
ANPR Automatic Number Plate Recognition.
ANPR system A collection of cameras, readers components linking to NAS.
CCTV Closed Circuit Television.
CAMERA The device used to capture an ANPR read.
CAPTURE RECORD The record of a vehicle recorded by NAS for a vehicle passing an ANPR camera including the ANPR READ, associated images and meta data.
COMMUNICATIONS LINKS The connections between the camera, any local infrastructure and the NAS.
CONTROLLER The competent authority which alone or jointly with others determines the means and purposes of the processing of personal data.

Part 3 data Protection Act 2018.
CPIA Criminal Procedure and Investigations Act 1996 and the CPIA Code of Practice
DPA Data Protection Act 2018
FOI Freedom of Information Act 2000
GDPR General Data Protection Regulations
GSC Government Security Classifications – (formerly the Government Protective Marking Scheme (GPMS).
GPS Global Positioning System.
HIT The report of a match of a vehicle registration mark (VRM) READ with a VRM that is included on a vehicle of interest list (VOI).
ISO Information Security Officer – The member of staff with responsibility for ensuring compliance with requirements for IT security.
ITHC IT Health Check – The process for ensuring that security provisions for IT are appropriate and in compliance with requirements that are current at the time of the check.
JCA Joint Controller Agreement under provisions of the Data Protection Act 2018.
JPEG Joint Photographic Expert Group image format.
LEA Law Enforcement Agency – Includes police forces and other agencies undertaking law enforcement activities. For the purpose of this document, LEAs shall only include those organisations listed at Annex A.
MIDAS Motor Insurance Bureau (MIB) data of uninsured vehicles.
MOPI Code of Practice for the Management of Police Information
NAC National ANPR Capability includes:

the NAS which is a single national system consisting of the functionality to enable use for operational response, investigation and intelligence purposes and a single national store of data, and,

the National ANPR Infrastructure (NAI) which is a network of ANPR cameras, communications links, firewalls and other related supporting components, that are the responsibility of LEA, that connect to the NAS.
NAI A network of ANPR cameras, communications links, firewalls and other related supporting components.
NAS National ANPR Service.
NASP National ANPR Standards for Policing first version published in 2013 and replaced by NASPLE recognising the applicability to all law enforcement agencies that access the NAS.
NASPLE National ANPR Standards for Policing and Law Enforcement.
National VOI List Nationally circulated lists that include stolen vehicles, vehicles requiring an operational response and vehicles within Schengen circulations.
NAPS National Accreditor for Police Systems – Responsible for confirming that police IT systems are in accordance with security requirements and authorising connection to national systems.
Network Connections The IT links between components of the NAC.
NPCC National Police Chiefs’ Council.
NPCC Vetting Policy The NPCC standards for vetting of staff for access to police information.
PERSONAL DATA Means any information relating to an identified or identifiable living individual.

‘identifiable living individual’ means a living individual who can be identified directly or indirectly, in particular by reference to:

an identifier such as name, an identification number, location data or an online identifier, or

One or more factors specific to the physical, physiological, genetic, mental, economic, cultural or social identity of the individual.

Data Protection Act 2018.
PNC Police National Computer.
READ The interpretation of a VRM by an ANPR system.
RIPA Regulation of Investigatory Powers Act 2000
RIPSA Regulation of Investigatory Powers (Scotland) Act 2000
Schengen The Schengen Information System will enable the authorities of signatory countries to have access to reports on persons and objects for the purpose of border checks and controls and other police and customs checks.
SMS A Standards format for text messaging.
VOI The details of a vehicle that are of interest to law enforcement for operational response or investigation purposes that is included on a list to enable it to be READ and for authorised staff to receive a report of that READ.
VRM Vehicle Registration Mark.

1. Introduction

This document prescribes the technical specifications for data within the National ANPR Service (NAS). National ANPR Standards for Policing and Law Enforcement (NASPLE) set out the standards that are required for the National ANPR Capability (NAC) to ensure compliance with relevant legislation in the operation and use of law enforcement ANPR. The information within this document is intended to support compliance and consistency in the operation and management of NAS by the police and other law enforcement organisations (hereafter referred to as LEA.

2. ANPR Read Records

2.1. System Testing

The only number that may be entered into any component of the NAS for the purpose of testing connectivity is QQ111QQQ.

2.2. Core Data Components

2.2.1. Vehicle Registration Mark (VRM) (Mandatory)

Where a camera has the capability to record images of vehicles passing within the field of view where no VRM is identified by the system, ‘QQQQQQQ’ must be recorded within the VRM field.

The required format must conform to the Standard Coding Format UTF-8character set. The VRM must contain no spaces.

2.2.2. Time (Mandatory)

Recorded and synchronised using standard time source techniques to Greenwich Mean Time (GMT) plus 0 (+0) at least once every 10 minutes, with accuracy to stratum level 3.

The required format is ‘dd/mm/yyyy hh:mm:ss’, in 24 hour format.

2.2.3. Location (Mandatory)

ANPR data must place a read in a location, accurate to within 10 metres. This location should have been ascertained through a Global Positioning System (GPS) device. In addition, all fixed-site ANPR cameras must have their GPS co-ordinates accurately recorded to within 5 metres.

The required format for recording a location is latitude and longitude in decimal degrees.

When a mobile ANPR system is unable to deliver an accurate GPS coordinate for a read, the GPS field must be populated with N0000000 E00000000.

2.2.4. Supporting imagery

Plate patch – showing the number plate only, (Mandatory for systems under ownership or control of an LEA).

A plate patch must be in JPEG format, 120x60 pixels and be no more than 3kB in size.

Overview – showing the vehicle in the context of the read zone (Optional). An overview image must be in JPEG format, no more than 25kB in size.

Where images obtained by a camera exceed 3kB for a plate patch or 25kB for an overview, these must be adjusted prior to forwarding to the NAS.

‘Geo Tagging’, if an accurate GPS Geo Location is available, then this detail may be added to images using Exif (Exchangeable image file format) (Optional

Other metadata

Column Format Mandatory Details
Feed ID Numeric Yes 2 character code as used by the Police National Computer (PNC) Also known as ‘Force ID’.
Source ID Numeric Yes Short integer (range 1 to 9999).
NRD ID Numeric Yes Short integer (range 0 to 9999).

(NRD ID zero (0) must be used to denote VRMs entered manually by an administrator of the ANPR system.)
Lane ID Alphanumeric No Optional text description.
‘Alias’ ID Alphanumeric No Optional textual description that does not disclose the exact location of a NRD.
Username String Yes Username of operator using the ANPR system.

When deployed in other circumstances, use ‘Unattended’.
Preset ID Integer No Short integer
Default value is 0
Used to indicate direction of travel on multi-lane CCTV cameras.

3. Data storage and management

3.1. Data loss and resilience

The NAS must not allow any data loss and be configured to provide to provide resilient capability.

3.2. Local system retention and deletion

Local components of NAC must be configured to enable retention of any data received from a camera at more than 7 days for a maximum of 48 hours and for deletion of that data within the following 24 hours.

3.3. Mobile Data Transfer

Local capability must be in place to support transfer of data from mobile ANPR units to the NAS within 48 hours of capture by the camera within the mobile system.

4. National Databases

The NAS must have the technical capability to run the following national databases, as a minimum - PNC; Includes ‘Fast Track’ ‘Extract’, ‘Schengen’ and ‘MMC’ data.

PNC Extract File

The PNC Extract File is available to forces at least three times every 24 hours and must be available to mobile systems at the earliest opportunity following receipt. All ANPR reads must match against the PNC Extract File should the live link to the PNC be unavailable.

5. Vehicle of Interest (VOI) Lists

VOI lists in NAS will be referenced to the LEA that creates and manages the list. In order to support the display of symbols within vehicle mounted systems the file name will be in accordance with the reference list at Annex A.

The following character mapping is to be used. All lists of VOI must conform to the following template, (Mandatory elements shown in bold text):

NB: Entries in ‘Standard Words’ section must match exactly those in the template for uploading into NAS

Column Description Standard Words Comment
1 VRM   No spaces, Alphanumeric characters only.
2 MAKE   0 to 20 characters, no carriage returns or commas.
3 MODEL   0 to 20 characters, no carriage returns or commas.
4 COLOUR   0 to 20 characters, no carriage returns or commas.
5 ACTION Stop


Assess

No Alert



Only one value per entry:
Action can include a requirement to STOP the vehicle and take action as described
Or
To assess in the context at the time the vehicle comes to notice to determine action.
Or
No Alert only to be used when a VOI list is submitted for monitoring purposes with no intention that any action is taken when the vehicle comes to notice

6 WARNING MARKERS No Warning Known

Warnings Present
Only one value per entry:
Generally, PNC ACTion should be used if warning markers are present. For VOI lists, ‘No Warning Known’ is most applicable.

If it is essential to use a VOI list and warning signals other than Firearms (FI), Weapons (WE), Violence (VI) are present then ‘Warnings Present’ should be used with the agreed PNC abbreviation (max of 3) entered.
If FI, WE, VI warning signals are present then a VOI must not be used (unless the intelligence is NOT for response) and a PNC ACTion marker created.
7 REASON Intel Serious Crime
Cloned
Low Crime
Drugs
Intel Sexual
Intel Low Crime
Offender Management
Impaired Driving
Documents
Disqualified
Other
No Insurance
No MOT
No Tax
No Keeper
LEA P1
LEA P2
LEA P3
LEA P4
LEA P5
LEA P6
Only one value per entry:

No Insurance, No MOT, No Tax and No Keeper MUST NOT be used as a REASON to create a VOI list entry. If intelligence relates to one of these categories, then DOCUMENTS must be used.

They are included in the template solely for the use of nationally populated lists to support NAS functionality.

8 INTEL 3X5X2   Enter grading without X or spaces.

Max 3 characters, no carriage returns or commas.
9 INFORMATION/ ACTION   Brief free text sufficient to add extra value and detail for the person dealing with activation.

Maximum of 198 characters including spaces and punctuation. No carriage return or commas.
10 LEA AND AREA   Include Force Name/ Area/ other LEA ref. Max 30 characters, no carriage returns or commas.
11 START DATE   Provide date in format [dd/mm/yyyy];
12 WEED DATE   Provide date in format [dd/mm/yyyy];

Entries will be weeded on date specified system as soon as possible (i.e. next weed cycle).
13 PNC ID   0 to 25 characters, no carriage returns or commas.
14 GSC marking OFFICIAL (or)

OFFICIAL-SENSITIVE
Only one marker to be used.
15 CAD   0 to 25 characters, no carriage returns or commas.
16 CONTACT   Provide details of 24hour point of contact for enquiries if vehicle stopped.

Max 60 characters, no carriage returns or commas.

Note

It is important that Vehicles of Interest (VOI) lists used to alert against in-car systems using Regulation 109 compliant software, only contain warnings that pose no immediate threat to officer safety.

Intelligence and information containing Firearms (FI), Weapons (WE) and Violence (VI) warning signals MUST be entered on a PNC ACTion report and NOT a VOI list. Changes to PNC ACTion guidance has been updated to accommodate this.

A regulation 109 spreadsheet tool has been developed to assist forces to create NASPLE compliant VOI spreadsheets. This is available from the National Administrators.

6. Real Time Matching

The NAS must provide real-time matching to PNC and other lists of VOI for all ANPR reads.

The system response time from a Vehicle Registration Mark (VRM) being captured by a camera to the hit notification response being delivered to a specific operator must not exceed 4 seconds for static, moveable, dual lane and CCTV Integrated systems, and 6 seconds for mobile ANPR systems.

To allow for this end-to-end performance requirement, the camera must deliver ANPR reads to the NAS within 2 seconds of capture for static, moveable, dual lane and CCTV [ANPR Integrated systems and within 4 seconds of capture for mobile ANPR systems.

The NAS must process that read against the PNC and other VOI databases and deliver any resultant match notification to the operator within 2 seconds of receipt of the read by the NAS for all systems.

7. Real Time Delivery of Data

Local LEA ANPR infrastructure must clearly display the current state of connectivity to the NAS and/or any time when data is not being sent to the NAS. In the event of a communications or systems failure, the LEA infrastructure must buffer that read data and deliver it to the NAS once the communications or failed systems have been restored. The real-time delivery of data is a priority and the delivery of any buffered data should take place in addition to delivery of real-time data.

8. Search and Export of Data

The NAS must provide for the identification and export of data to enable identification using any of the following criteria:

  • Vehicle Registration Mark (VRM);

  • Date and time parameters;

  • by camera identification;

  • by location co-ordinates;

  • by ‘geo plotting’

  • direction of travel (desirable)

9. Interoperability

Systems must enable interoperability between LEAs and the NAS to allow:

  • Real-time matching of reads against lists of VOI and the real-time delivery of hits

  • Remote research in accordance with prevailing researching guidelines

  • NAS read searching for national data searches and data mining in accordance with the NAS Business Rules, as defined within current NASPLE

  • Distribution of lists of vehicles of interest to the NAS

  • Transfer of data and all associated images between LEA ANPR Infrastructure and the NAS.

Annex A

Vehicle of Interest List (VOI) Naming Convention

In order to display the name of the organisation creating the VOI list within symbols in vehicle mounted systems, character mapping is required. A VOI list file name will begin with the organisations PNC ID followed by an underscore (for example 07_Cheshire VOI List); the agreed force abbreviation will be displayed in the bottom ‘white’ section of the VOI symbol (in this example CHESH would be displayed). The following character mapping is to be used:

Character at start of VOI File name followed by underscore Display in bottom white section of VOI symbol
52 A&S
40 BEDS
93 BTP
35 CAMBS
07 CHESH
48 COLP
59 CNC
17 CLEV
03 CMBRIA
30 DERBYS
50 D&C
55 DORSET
94 DVLA
201 DVSA
11 DURHAM
63 DPP
42 ESSEX
53 GLOS
06 GMP
61 GWENT
44 HANTS
41 HERTS
88 LEA
16 HUMB
46 KENT
04 LANCS
33 LEICS
32 LINCS
05 MERPOL
02 METPOL
24 MOD
36 NFOLK
60 NWP
12 NYP
34 NHANTS
10 NORPOL
31 NOTTS
90 PSOS
98 PSNI
62 SWP
14 SYP
21 STAFFS
37 SFFOLK
45 SURREY
47 SUSSEX
43 TVP
23 WARWCK
22 WMERCA
20 WMIDS
13 WYP
54 WILTS
735 BCH
CMPG CMPG
NWMPG NWMPG
LEA LEA
TUTELAGE TULAGE
MIDASGOLD MIBGLD
TRIVIUM TRVIUM
TUTELAGEPLUS TUPLUS
TUTELAGEMOT TU MOT
TUTELAGEVED TU VED
MIDASGOLD MIBGLD
MIDASCOMM MIBCOM
NATIONALROADS NRPOII

Document Revisions

Version 3.1

May 2021.

Minor revision of VOI template in line with Reg 109 requirements.

Version 3.2

December 2021.

Minor revision of VOI list template at request of Technical Advisory Group to ensure clarity and consistency with Reg 109 supplier document.

Version 3.3

January 2022.

Minor revision to Section 4 and VOI list template.

Version 3.4

January 2022.

Update wording section 4 and additions to VOI list naming convention.