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The ECE+EUDC test cycle is performed on a chassis dynamometer. The cycle—also known as the MVEG-A cycle is used for emission certification of light duty vehicles in Europe [EEC Directive 90/C81/01].
The entire cycle includes four ECE segments, repeated without interruption, followed by one EUDC segment. Before the test, the vehicle is allowed to soak for at least 6 hours at a test temperature of 20-30°C. It is then started and allowed to idle for 40s.
Effective year 2000, that idling period has been eliminated, i.e., engine starts at 0s and the emission sampling begins at the same time. This modified cold-start procedure is also referred to as the New European Driving Cycle or NEDC.
Emissions are sampled during the cycle according the the “Constant Volume Sampling” technique, analyzed, and expressed in g/km for each of the pollutants.
The ECE cycle is an urban driving cycle, also known as UDC. It was devised to represent city driving conditions, e.g. in Paris or Rome. It is characterized by low vehicle speed, low engine load, and low exhaust gas temperature.
The above urban driving cycle represents Type I test, as defined by the original ECE 15 emissions procedure. Type II test is a warmed-up idle tailpipe CO test conducted immediately after the fourth cycle of the Type I test. Type III test is a two-mode (idle and 50 km/h) chassis dynamometer procedure for crankcase emission determination.
The EUDC (Extra Urban Driving Cycle) segment has been added after the fourth ECE cycle to account for more aggressive, high speed driving modes. The maximum speed of the EUDC cycle is 120 km/h. An alternative EUDC cycle for low-powered vehicles has been also defined with a maximum speed limited to 90 km/h.

The U.S. FTP-72 (Federal Test Procedure) cycle is also called Urban Dynamometer Driving Schedule (UDDS) or LA-4 cycle [CFR 40, 86, App.I]. The same engine driving cycle is known in Sweden as A10 or CVS (Constant Volume Sampler) cycle and in Australia as the ADR 27 (Australian Design Rules) cycle.
The cycle simulates a urban route of 12.07 km (7.5 mi) with frequent stops. The maximum speed is 91.2 km/h (56.7 mi/h) and the average speed is 31.5 km/h (19.6 mi/h).
The cycle consists of two phases: (1) 505s (5.78 km at 41.2 km average speed) and (2) 864s. The first phase begins with cold start. The two phases are separated by stopping the engine for 10 minutes. In the U.S. a weighting factors of 0.43 and 0.57 are applied to the first and second phase, respectively. In Sweden both phases have the same weighting factors. Emissions are expressed in g/mile or g/km.

The FTP-75 (Federal Test Procedure) has been used for emission certification of light duty vehicles in the U.S. Effective model year 2000, vehicles have to be additionally tested on two Supplemental Federal Test Procedures (SFTP) designed to address shortcomings with the FTP-75 in the representation of (1) aggressive, high speed driving (US06), and (2) the use of air conditioning (SC03).
The FTP-75 cycle is derived from the FTP-72 cycle by adding a third phase of 505s, identical to the first phase of FTP-72 but with a hot start. The third phase starts after the engine is stopped for 10 minutes. Thus, the entire FTP-75 cycle consists of the following segments:

1. Cold start phase
2. Transient phase
3. Hot start phase.

The following are basic parameters of the cycle:

1. Distance traveled: 11.04 miles (17.77 km)
2. Duration: 1874s
3. Average speed: 21.2 mph (34.1 km/h).

The emissions from each phase are collected in a separate teflon bag, analyzed and expressed in g/mile (g/km). The weighting factors are 0.43 for the cold start, 1.0 for the transient phase and 0.57 for the hot start phase.
The FTP-75 cycle is known in Australia as the ADR 37 (Australian Design Rules) cycle.

The US06 Supplemental Federal Test Procedure (SFTP) was developed to address the shortcomings with the FTP-75 test cycle in the representation of aggressive, high speed and/or high acceleration driving behavior, rapid speed fluctuations, and driving behavior following startup.
The cycle represents an 8.01 mile (12.8 km) route with an average speed of 48.4 miles/h (77.9 km/h), maximum speed 80.3 miles/h (129.2 km/h), and a duration of 596 seconds.

The SC03 Supplemental Federal Test Procedure (SFTP) has been introduced to represent the engine load and emissions associated with the use of air conditioning units in vehicles certified over the FTP-75 test cycle.
The cycle represents a 3.6 mile (5.8 km) route with an average speed of 21.6 miles/h (34.8 km/h), maximum speed 54.8 miles/h (88.2 km/h), and a duration of 596 seconds.

The EPA NYCC test has been developed for chassis dynamometer testing of light-duty vehicles (CFR 40, 86, App.I). The test simulates low speed urban driving with frequent stops.
The following are basic parameters of the cycle:

1. Duration: 598 seconds
2. Distance: 1.18 miles = 1.89 km km
3. Average speed: 7.1 mi/h = 11.4 km/h
4. Maximum speed: 27.7 mi/h = 44.6 km/h

The HWFET cycle is a chassis dynamometer driving schedule, developed by the US EPA for the determination of fuel economy of light duty vehicles [40 CFR part 600, subpart B].
The following are some characteristic parameters of the cycle:

1. Duration: 765 seconds
2. Total distance: 10.26 miles (16.45 km)
3. Average Speed: 48.3 mi/h (77.7 km/h)

The California Unified Cycle (UC), Figure 1, is a dynamometer driving schedule for light-duty vehicles developed by the California Air Resources Board. The test is also referred to as the Unified Cycle Driving Schedule (UCDS). One of the applications of the UC cycle is testing of vehicles fitted with direct ozone reduction technologies (the Supplemental Federal Test Procedure, SFTP, was used for that purpose earlier).
The UC test has a similar three-bag structure, but is a more aggressive driving cycle than the federal FTP-75; it has higher speed, higher acceleration, fewer stops per mile, and less idle time. The UC test is run in the following manner: Bags 1 and 2 are run consecutively, followed by a ten minute hot soak, then Bag 3 which is a duplicate of Bag 1. Overall cycle emissions are calculated in the same manner as the weighted, overall FTP-75 formula, taking actual mileage from the UC into account.
The following are some characteristic parameters of the cycle:

• Unified Cycle:
• Duration: 1435 seconds
• Total distance: 9.8 miles (15.7 km)
• Average Speed: 24.6 mi/h (39.6 km/h)
• Bag 1:
• Duration: 300 seconds
• Total distance: 1.2 miles (1.9 km)
• Bag 2:
• Duration: 1135 seconds
• Total distance: 8.6 miles (13.8 km)

The IM240 test is a chassis dynamometer schedule used for emission testing of in-use light duty vehicles in inspection & maintenance programs implemented in a number of states.
It is a short, 240 second test representing a 1.96 mile (3.1 km) route with an average speed of 29.4 mile/h (47.3 km/h) and a maximum speed of 56.7 mile/h (91.2 km/h).

The Standard Road Cycle (SRC) and Standard Bench Cycle (SBC) were introduced by the US EPA in 2005 for predicting the useful life emissions of new light-duty vehicles under the CAP 2000 program. The CAP 2000 durability provisions and the SRC/SBC tests are applicable mostly to gasoline cars with three-way catalysts.
SRC. The Standard Road Cycle is a whole vehicle aging cycle. Manufacturers can demonstrate the emission levels of new vehicles at the end of their useful life period by running a vehicle on the SRC cycle for the full useful life mileage of the vehicle (e.g., 120,000 miles for Tier 2 light-duty vehicles).
The SRC, shown in Figure 1, consists of seven laps of 3.7 miles each. The average speed on the SRC is 46.3 mph, the maximum cruise speed is 75 mph, and the acceleration rates range from light to hard accelerations. Most accelerations are moderate and there are no wide-open-throttle accelerations. The SRC contains 24 fuel-cut decelerations. The deceleration rates range from coast-down (no brake force applied) to moderate.
SBC. In lieu of running the SRC test over the full useful life mileage, manufacturers can perform accelerated aging on an engine test bench. The aging is performed by repeated runs of the Standard Bench Cycle for a required period of time. The SBC time period is determined by a complex calculation based on the catalyst temperature profile measured during the SRC cycle.
The SBC, Figure 2, is a 60-second cycle defined based on the catalyst temperature, engine air/fuel (A/F) ratio, and the amount of secondary air injection which is added in front of the catalyst (using shop air). The catalyst bed temperature is controlled at 800°C during the “stoichiometric” condition, and at 890°C during the “rich” condition.

The 10 mode cycle [Japanese Industrial Safety and Health Association, JISHA 899, 1983] was used for emission certification of light duty vehicles in Japan. It has been replaced by the newer 10-15 mode cycle.
The 10 mode cycle simulates urban driving conditions. One segment of the cycle covers a distance of 0.664 km at an average speed of 17.7 km/h and lasts 135 s (Figure 1). The maximum speed is 40 km/h.
The entire cycle begins with a 15 minutes warm-up at 40 km/h, followed by six repetitions of the same segment. Emissions are measured over the last five segments (so the emission measurement period represents a route of 3.32 km, completed in 675 s). Emissions are expressed in g/km.

The 10-15 mode cycle is currently used in Japan for emission certification and fuel economy for light duty vehicles. It is derived from the 10 mode cycle by adding another 15-mode segment of a maximum speed of 70 km/h. Emissions are expressed in g/km [Japanese Industrial Safety and Health Association, JISHA 899, 1983].
The entire cycle includes a sequence of a 15 minute warm-up at 60 km/h, idle test, 5 minute warm-up at 60 km/h, and one 15-mode segment, followed by three repetitions of 10-mode segments and one 15-mode segment. Emissions are measured over the last four segments (3×10-mode + 1×15-mode, Figure 1).
The distance of the cycle is 4.16 km, average speed 22.7 km/h, duration 660 s (or 6.34 km, 25.6 km/h, 892 s, respectively, including the initial 15 mode segment).