Most people will immediately offer their seat on public transit to someone who is clearly disabled, pregnant, elderly or walking with a cane.
But not everyone with a difficulties riding transit can be spotted so easily.
That's the case for New Westminster resident Jason Bosher, who rides the SkyTrain every day in "a great deal of pain" because he must stand while otherwise healthy looking people sit in seats reserved for the disabled.
Bosher, who has rheumatoid arthritis and spinal injuries, said he knows he's only one of the "invisible disabled" - people whose disabilities are not immediately apparent to outsiders.
"There's got to be more people like me that don't look like they're disabled, but are, and have to stand. For me it's a very painful thing to do," he said. "There's got to be other people like me who are riding the train in pain and in silence."
Bosher compared the situation to an able-bodied person taking a handicapped parking spot - something a disabled person may badly need but must display their disability with the government-provided sticker in order to get. Bosher said not everyone is comfortable displaying his or her disability so openly, or confronting someone in a disability priority seat.
"It's a real personal thing, and it's not something you really want to talk to people about on the SkyTrain," he said
He added that he runs the risk of asking another "invisible disabled" person to vacate a seat, and when he does manage to get a seat, he'll often get dirty looks from other riders who assume he's able-bodied.
"It's kind of a conundrum," he said At the very least, Bosher said transit riders who don't need the seat should be reminded to leave the seats open for those who really need them, whether they look like it or not.
TransLink spokesman Ken Hardie said priority seating for people with disabilities is "primarily self-managed," and most people will offer their seat immediately if it looks like someone really needs it.
When it comes to those who have disabilities that don't appear in any outward ways, or those who are temporarily disabled, he recommends using the platform phone at any of the SkyTrain stations to call an attendant "who can see them onto the train and explain that this person needs a seat."
"There would be no problem with that," Hardie said.
Paul Caune, executive director of Civil Rights Now!, a Burnaby-based advocacy group that lobbies for tougher disability legislation, said Bosher's situation is somewhat common, but there is currently no law that could guarantee him a seat on any public transit in Canada.
"We have been advocating for legislation, based on legislation in other jurisdictions, that would prevent these situations from arising, or if they did, we would have the tools to rectify them," he said, referring to the United States' Americans with Disabilities Act. "There's no mandatory obligation on the part of TransLink to run accessible transportation."
Caune said Bosher shouldn't necessarily be the one to confront someone in a disability priority seat, but he should be comfortable asking an attendant.
"The risk of that is the person sitting there could be belligerent and may become violent. It should be incumbent upon TransLink to enforce the designated seats," Caune said.