VANCOUVER, B.C. - A security supervisor at Vancouver's airport says he checked Robert Dziekanski's pulse as he waited for firefighters to arrive after the Polish man was stunned by an RCMP Taser.

Trevor Enchelmaier told a public inquiry Monday that he arrived as Dziekanski was writhing on the floor of the airport's international arrivals lounge in the early morning of Oct. 14, 2007.

Enchelmaier said he restrained Dziekanski's legs as officers placed handcuffs on him and after Dziekanski became motionless, he saw an officer trying to check for a pulse while wearing leather gloves.

"That's what made me check his pulse, they were trying to do it with their gloves on," Enchelmaier, who has first-aid training, told the inquiry.

"You're not going to be able to feel for a pulse very well with leather gloves on."

Enchelmaier said he checked Dziekanski's pulse three times as he lay on the floor of the airport, each time several minutes apart, and felt a pulse every time.

During the second and third check, he said he also leaned over to listen for breathe and concluded that Dziekanski was, in fact, breathing.

His said his third check was about two minutes before members of the Richmond Fire Department arrived.

The issue of whether police or anyone else were monitoring Dziekanski before emergency medical services reached the scene has become a key issue at the inquiry.

The fire captain on duty that night testified earlier that when he and his crew arrived, no one was near Dziekanski and he didn't believe anyone had been monitoring him.

By that point, Dziekanski had no pulse, wasn't breathing, and Capt. Kirby Graeme believed he was already dead.

But Enchelmaier said two minutes earlier, Dziekanski was unconscious but alive.

"I noticed a pulse, it was a slow pulse, still a clear pulse there in his carotid pulse," said Enchelmaier. "And the breathing was slow, low breathing, but still clearly breathing."

Witnesses have varied as to whether anyone was checking Dziekanski after he was shocked. Some have testified they didn't see anyone near Dziekanski checking the man or performing first-aid, while others have said he was checked once or twice.

Enchelmaier is seen on a bystander's video checking Dziekanski's pulse at least once, but the footage ends soon after.

The RCMP officers have not yet appeared but are expected to testify at the inquiry as early as next week.

Meanwhile, another security guard testified Monday that he was ordered by a supervisor to block the view of the public and a bystander's video camera as RCMP officers restrained Dziekanski.

Fabian D'Sa, who arrived after Dziekanski was stunned, is seen on a video of the incident entering the centre of the frame, partially blocking the view of three police officers restraining Dziekanski.

D'Sa said he was told to stand there by Enchelmaier, although Enchelmaier later said he didn't know there was anyone filming the scene with a video camera.

"To have some privacy. Mr. Robert (Dziekanski)'s privacy," D'Sa testified when asked why, on the bystander's video, he is seeing walking into view.

Outside the inquiry, D'Sa repeatedly referred questions to the airport's lawyer, but interrupted when a reporter asked about why he blocked the view of what happened.

"If it was you, I would have done the same thing," said D'Sa.

"I would have given you privacy as well, because you're an individual. It's not just Robert, it's everyone. It's a question of, you don't want to see yourself weeks later on YouTube."

On the video, D'Sa only stays in position for about 30 seconds before walking away, he said, to meet firefighters outside the airport.