In the aftermath of the Toronto van attack earlier this week, concerned citizens are reaching out to first aid organizations to freshen up on their skills.

St. John Ambulance, an organization dedicated to teaching and training the public in first aid, says it has seen a surge in interest for its courses since the Monday afternoon attack that claimed the lives of 10 people.

Dianne Rende, executive director of the St. John Ambulance’s Peel Dufferin branch, says a simple two-day course can help someone’s ability to perform the first aid needed to save a life.

“If they've had very good training which involves a lot of practice, actually physically doing it, they don't have to rely on thinking through the process -- muscle memory kicks in,” she told CTV Toronto.

Roula Massin, a witness to the attack who gave CPR to several victims, says improved first aid training among the public is necessary. She called for people with certified CPR training to help the victims, but not enough witnesses had the proper skills.

“Please, every person should know CPR,” she said.

It’s not just incidents of mass casualties where this kind of training comes in handy. Earlier this month in Vancouver, a passenger on a ferry performed CPR on a man in medical distress and ultimately saved the man’s life.

The staff of Drake Property Management, a rental property company in Brampton, Ont., are among the groups choosing to take a course following news of the attack.

“It just made me think instantly: ‘Would my staff and would our boots-on -the-ground (employees) at our properties know what to do if this would happen to us?’” said Brittany Pulis, who booked the classes for the company.

“(On Monday), you really saw instantly that knowing CPR and first aid can make the difference between life and death.”

Pulis says all 20 staff at Drake Property Management will be taking a first aid training course in the coming weeks and hopes other companies follow suit.

St. John Ambulance and Canadian Red Cross offer dozens of courses each week across Canada. St. John Ambulance says more than 550,000 Canadians are trained in CPR each year.

With a report from CTV Toronto’s Pauline Chan