A gust of wind catches a piece of construction material being moved by a worker on Monday morning. (CBC)

Inspectors surveyed a skyscraper under construction in downtown Calgary on Monday following a weekend incident that saw a piece of scaffolding fly off the building.

The debris fell off the 19th floor of a tower under construction at the Penn West Plaza on Ninth Avenue S.W. on Saturday night, and hit a parkade ramp. No one was hurt, but the city issued a stop-work notice.

On a windy Monday morning, city and provincial inspectors were at the site and workers could be seen moving material around.

Ald. Ric McIver said he will talk to the city's building inspectors to find out how to prevent similar incidents.

"I don't know what is going on, but I do know there is no excuse for it," McIver said. "And I do know that we need to put our heads together and find whatever method it takes to inspire people to do the job right or take away their ability to put stuff up in the sky in the first place."

Chris Chodan, a spokesman for Alberta Employment, said two provincial workplace safety officers were on the site — where Centron Construction Group is the general contractor — on Monday.

"We are trying to find out now if it is because of the wind or what caused [the debris] to come down," he said. "Did they have the proper procedures in place? Are the workers trained properly? Do they have the right equipment for the job? All those kinds of things."

3rd incident since 2007

A worker died on the same building site in May. Lance James Orr, 27, was crushed by 1,800 kilograms of building materials that slipped out of a crane sling.

At a second Penn West Plaza tower, which has since been completed, a worker suffered severe head injuries in a fall from the 11th floor to the ninth floor in 2007.

Centron and Pagnotta Industries, a subcontractor, were charged with failing to ensure they were complying with Alberta's Occupational Health and Safety Act in connection with that incident.

Centron is "extremely disappointed" about the weekend incident, president Cole B. Harris said in a statement released on Monday.

"Centron has an excellent safety program and an overall excellent safety record over the past 25 years. Safety is a key component in all of our projects, and we hold ourselves and subcontractors to high standards for training and on-the-job safety," he said.

Near site where child killed

Penn West Plaza is only a block from another worksite where a piece of debris crashed to the street below on Aug. 1, killing three-year-old Michelle Krsek and injuring her father and brother.

On Friday, the city announced charges in that case against the building owner, Germain Residences Ltd., the general contractor, Grenville-Germain Calgary Limited Partnership, and the subcontractor, Flynn Canada Ltd. Each was charged with one count of allowing an unsafe condition.

A stop-work order has been issued for construction on the Penn West Plaza tower. (CBC)

That incident also prompted a review of 20 highrise construction sites in the city, during which inspectors handed out nine compliance orders.

Alfred Johnson, a construction worker in downtown Calgary, said Monday he often thinks about the three-year-old girl while he is working.

"All the time. I have a 10-year-old son so I wouldn't want to see a piece of my building come down and hit him. We got to take precautions the best we can," he said.

At his site, six workers are often patrolling to make sure construction materials are secured, he said.

"There is no excuse for scaffolding to fall off a building. Scaffolding should be built properly, it shouldn't fall off a building, no matter how much wind comes."