The British Rail Class 222 Meridian is a group of 5- or 7- car diesel-electric multiple-unit high-speed passenger train capable of 125 mph (200 km/h).

In common with the Class 220s, B5000 lightweight bogies are used - these are easily recognisable since the entire outer surface of the wheel is visible, with inboard axle bearings.

The four-car units ordered by Hull Trains had an option when constructed to be extended to five cars if required.

[11] With the exception of EMR Connect services, no route operated by East Midlands Railway is fully electrified.

When the trains were ordered, Midland Mainline overestimated the number of first-class passengers, and the four-car Meridians had less standard-class seating than the three-car Turbostars they replaced.

The five-car trains are mainly used between London St Pancras and Sheffield, Nottingham or Corby on semi-fast services, and at off-peak times.

[2] All are scheduled to be returned to Eversholt Rail Group in the future once Class 810s replace them on EMR Intercity services.

[24][25] In 2005, HSBC Rail took delivery of the seven nine-car trains planned for use by Midland Mainline on its London-Leeds service, but the trains were left idle when the Strategic Rail Authority prevented Midland Mainline from operating this service.

HSBC Rail made contact with Northern Ireland Railways and Iarnród Éireann, with a view to their leasing these units for use by Enterprise.

[26] Using these trains on the Belfast-Dublin line was one of a number of options, which also included the purchase of additional 22000 Class railcars or cascaded coaching stock.

The trains would have required significant modification to be used by Northern Ireland Railways, including reducing each train from nine to eight cars (the maximum length of stations on the Belfast-Dublin line), and converting them from standard gauge to Irish gauge (5 ft 3 inches).

Grand Central, on the announcement of its open-access operation to Sunderland in the summer of 2006, planned to run its services using five Class 222 units, with the intention of starting by the end of that year.