Installation Safety
The Energy Department of the Velocity Interoperability Network is responsible for the safety of electrical, gas and heat installations at the sites of the Velocity Interoperability Network. Every installation is assigned to one of five classes, each with an inspection interval. New and altered installations must be certified by the Department before they are energised, and only installers on the Department's register may work on them.
The regime described on this page applies at every site of the Network from 6 September 2026. It replaces the separate arrangements that member organisations had each maintained, and the registers of installations and installers those organisations kept were transferred to the Department during the transition period.
Reporting a dangerous installation
Classes of installation. The table below records the five classes, the installations each covers, the inspection interval and the number of installations on the register at establishment.
| Class | Installations | Inspection interval | On the register |
|---|---|---|---|
| Class A | Installations operating above 1,000 volts, including substations, switching stations and high-voltage cables | Annually | 38 |
| Class B | Low-voltage fixed installations at Network sites: offices, workshops, plant rooms and external lighting | Every three years | 1,742 |
| Class C | Generating plant, battery storage and their protection systems | Annually, with a full examination every five years | 9 |
| Class D | Gas and heat installations, including boiler plant, gas pipework and the Southbank heat network | Annually | 231 |
| Class E | Installations in residential accommodation for the staff of member organisations | Every five years and on each change of occupant | 296 |
Certifying a new or altered installation. The steps below apply to every new installation and to every alteration of an existing one, in every class.
Step 1: Notify the Department before work begins
The site operator writes to the Department describing the new or altered installation, its class, its location and the registered installer engaged. Work on a Class A, C or D installation may not begin until the Department has acknowledged the notification.
Step 2: Engage a registered installer
Only an installer on the Department's register may carry out the work. The register records each installer's name, the classes of installation they may work on and the date their registration falls due for renewal.
Step 3: Complete the work and submit the installer's report
On completion the installer tests the installation and submits a completion report to the Department, with the test results, drawings and the equipment schedule.
Step 4: Inspection
An inspector of the Department examines the installation against the completion report. Class A, C and D installations are inspected in every case; Class B and E installations are inspected in a sample of not less than one in five and otherwise certified on the installer's report.
Step 5: Certificate of safety and entry on the register
Where the installation is satisfactory the Department issues a certificate of safety, enters the installation on the register with its class and next inspection date, and authorises energisation. Where it is not, the Department lists the defects to be remedied before re-inspection.
Step 6: Periodic inspection
The installation is inspected at the interval for its class. The Department writes to the site operator not less than four weeks before an inspection falls due. The certificate lapses if an inspection is missed and the installation may not be used until it is renewed.
Duties. The safety of installations depends on site operators, installers, occupants and the Department each discharging their duties.
- Site operators
- Keep a record of every installation at the site and its certificate, make installations available for inspection when due, report any defect or damage to the Department, and ensure that only registered installers work on them.
- Registered installers
- Work only within the classes for which they are registered, test every installation on completion, submit a completion report within ten working days, and report to the Department any existing installation they find to be dangerous.
- Occupants of residential accommodation
- Allow access for the inspection of Class E installations, report faults to the site duty officer, and refrain from altering fixed wiring, gas appliances or heating plant.
- The Department's inspectors
- Twenty-two inspectors certify new installations, carry out periodic inspections, audit a sample of installer reports each quarter, and attend reports of dangerous installations within one working day for Classes A, C and D and within three working days for other classes.
The registers at establishment. The figures below record the position of the registers on 6 September 2026 and the inspection activity of the transition period.
| Measure | Number |
|---|---|
| Certified installations on the register | 2,316 |
| Registered installers | 148 |
| Installations with an inspection falling due before 31 December 2026 | 412 |
| Inspections carried out during the transition period | 252 |
| Installations found defective during the transition period | 19 |
The 412 installations whose inspection falls due before the end of 2026 are being scheduled by the Installation Inspectorate in order of the date due, and site operators will be written to not less than four weeks in advance. The nineteen installations found defective during the transition period have been isolated pending repair; none was a Class A or Class C installation.
Installations are connected to the Network supply under an application recorded on the Connections page. Renewable installations under the Renewable Programme are certified in Class C. Inspection figures are reported quarterly on the Statistics page. Notifications, completion reports and enquiries may be sent to contact@energy.gov.vin.