Emissions testing on buses has been streamlined in a move that it is hoped will make it simpler for manufacturers to access funding to put more low emission buses on the road.
Developers say that the new testing cycle is more challenging than its predecessors, as it will place vehicles under more demanding testing conditions.
To qualify as an Ultra Low Emission Bus (ULEB) and to have access to funding under the governments 48 ULEB funding scheme manufacturers must test their vehicle over the UK Bus Cycle test procedure.
A separate test cycle had also been used by TfL to compare the emissions performance of different bus technologies.
From yesterday (1 November) a unified test procedure is being used by both Transport for London (TfL) and the national Ultra Low Emission Bus (ULEB) accreditation scheme.
The use of the same test will enable manufactures to test a vehicle once and for it to be eligible for use in both the London market as well as qualifying for national grant schemes, according to the Low Carbon Vehicle Partnership (LowCVP), which has helped to develop the test procedure.
It is hoped that by bringing the two testing cycles together accredited buses will be eligible for use in both the London market as well as qualifying for national grant schemes, and make it easier for manufacturers to place new vehicles on the market.
The new test applies to all new models. Those that have already achieved LEB or ULEB status will continue to be classed as such.
The new test will be called the UK Bus Cycle (UKBC) and will comprise of the London Bus Cycle (LBC) phase and a rural phase.
The LBC section has been developed from the previous Millbrook London Test Bus (MLTB) cycle which has been used by TfL.
In a statement, LowCVP said: The LowCVP Bus Working Group and TfL have worked closely over the last two years to refine the Millbrook London Test Bus (MLTB) and LUB (LowCVP UK Bus) to reflect modern requirements and combine them into one common test.
The new test is more challenging for manufacturers as it includes requirements for ancillary loads such as lighting and heating to be switched on, with the test chamber temperature set to 10C more demanding for exhaust aftertreatment systems.
As part of the ULEB Scheme conditions, buses must have approved test certificates in order to receive government funding. These certificates are published on the LowCVPs Low Emission Bus Hub web pages enabling comparison of vehicle emissions performance.
The certificates feature all regulated emissions including nitrogen oxides (NOx) and particulates (PM), as well as fuel consumption and well-to-wheel greenhouse gas emissions per passenger kilometer.
This transparency is unparalleled in any other vehicle accreditation scheme in the UK or the world, LowCVP said.