It’s a safe bet that B.C.’s 1,000-plus escalators and moving walkways are never all in working order at any one time.

Just ask anyone who frequents transit stations, department stores or any other public space that uses the people-moving units.

Escalators break down and just like any complex piece of machinery, they require regular maintenance that can keep them out of service for hours, days or a lot longer if there’s a problem in getting the right replacement parts.

“They’re a moving piece of machinery and anything that moves is bound to have problems,” said Norm Langerhorst, the wayside maintenance director for the B.C. Rapid Transit Company. It’s the operating company for the Expo and Millenium line SkyTrain. “These are the first things our customers see when they come into our system, so if they don’t get that ride and they have to use the stairs instead, I can understand their frustration.”

Langerhorst and his team of 31 technicians and support staff are responsible for maintaining 76 escalators on the two lines, some of which have been around since 1985. The Canada Line’s 38 escalators are maintained by elevator/escalator manufacturer Schindler.

One of the lengthiest escalator shutdowns in SkyTrain’s history occurred when the 109-step up escalator at Commercial-Broadway station was out of service for six months in 2013.

Maintenance workers fixed several problems in the unit before determining the escalator needed a new bull gear, the mechanism responsible for moving a chain along the track. The part had to be ordered from Germany and took several weeks to arrive before the machinery could be resolved.

It took about four months last year to install two new escalators at The Bay’s downtown Vancouver outlet, as the store gradually replaces moving stairways that date back to the 1950s.

HBC store planning project manager Bill Stanbury said it routinely takes months to replace the antiquated units but it should make for fewer lengthy shutdowns in the future.

“When they’re that old, the problem becomes that nobody has parts,” he said. “So every time it breaks down, it takes you three times as long to get it fixed because you have to machine the part.”

Vandalism can also force the shutdown of escalators, including when some people try to pull off a unit’s rubber handrails.

Langerhorst said many of the 30-year-old escalators on the Expo line were rated to last just 20 years, so they require more maintenance because they’re living on borrowed time.

TransLink has occasionally taken parts from one working escalator — causing it to temporarily shut down — to fix a busier broken escalator. But that’s a last-resort scenario.

Langerhorst said TransLink officials are increasing their inventory of escalator parts. Work on a longer-term solution begins in August 2016 with the start of a five- to eight-year program to replace many Expo Line escalators.

The program will cost an estimated $16 million for 26 new escalators — including eight at Metrotown station, four at Commercial-Broadway and four at New Westminster station.

Annual inspections of SkyTrain escalators usually last four or five days and involve taking the unit apart, checking all working parts, replacing gear box oil and cleaning away everything that falls below the steps into the escalator’s inner workings.