A Fuxing bullet train left Mudanjiang Railway Station in Heilongjiang province early on Sunday morning for a full-line test run on the high-speed railway linking Mudanjiang and Jiamusi in the province.

It was the first time a Fuxing bullet train has run on China's easternmost high-speed line, which is located in an extremely cold region.

"The CR400BF-G Fuxing bullet trains are designed to withstand the climate in extremely cold areas that may be hit by blizzards and temperatures as low as -40 C," said Zhang Lin, a staff member from the operation workshop of China Railway Harbin Group's bullet train section. "Designers chose materials with better airtightness for the equipment compartment, which can keep out the snow and cold air.

"Designers also installed more sanding gear in the train, which may help increase traction and prevent the wheels slipping in snowy weather. Under the control of the train driver, sand in the sand box will be distributed to the rail surface while running."

Since June 10, different types of bullet trains have been put into use in test runs to ensure the line can operate safely, the group said.

The dynamic detection and debugging of rail track, communication, signal, power supply, disaster monitoring and other systems has been completed and the whole system has been optimized, the group said.

It has also trained crews on safety measures, service etiquette and emergency procedures in recent months.

"Bridges and tunnels account for more than 50 percent of the whole rail line, as well as 55 steep ramps," said Lu Zhen, deputy head of the Mudanjiang passenger service section. "We have organized a training course focused on passenger evacuation while passing the bridges and tunnels to ensure an orderly emergency response."

Construction started in November 2016. The 371-kilometer line, designed for trains running at up to 250 kilometers per hour, will cut travel time between Mudanjiang and Jiamusi from seven to two hours.

"I have long been looking forward to the opening of the new line," said Huang Kai, 38, an English teacher from Jiamusi No 11 Senior High School. "My wife's parents live in Mudanjiang, so we often travel between the two cities, especially as they are getting older.

"Our trip will become easier after the line's opening and it will be a special experience to have the chance to take a Fuxing bullet train in Heilongjiang."