BOMB SNIFFING - An unidentified vistor to the CN Tower passes through a bomb sniffing device installed at the base of the CN Tower, as as a security guard watches the procedure. Visitors to the tower are subjected to this security check before boarding the elevators. A series of air bursts starting from the top and working down take samplings of of the air from the person subjected to the check. DICK LOEK / THE TORONTO STAR (Photo by Dick Loek/Toronto Star via Getty Images)
