Do they have electronic sniffing machines for C4? Dogs may sense that stuff but they don't use them 24/7.
I don't know if they use them in Canada.
Airport security "puffers" for bomb detection ditched by TSA
By Jeffrey Leib
The Denver Post
Posted: 05/22/2009 01:00:00 AM MDT
Want an airport "puffer" machine, officially called an explosive trace portal, for your living room?
The U.S. Transportation Security Administration is scrapping the bomb-detection technology, in part because of high maintenance costs for the 94 machines currently deployed at 37 U.S. airports. Denver International Airport has three of the walk-through screening devices, one at each of DIA's security checkpoints.
The TSA also has 113 such machines that it never deployed, said spokeswoman Carrie Harmon. The TSA's plan to junk the puffers was first reported by USA Today.
The agency spent about $30 million for the 207 machines, which also have incurred about $6 million in maintenance costs since they were introduced in 2004, Harmon said. At DIA, the machines, made by Smiths Detection, have been used for secondary screening of airline passengers.
They blow puffs of air over travelers while they stand in the portal. The device collects an air sample and analyzes it for explosive residue.
"The reason we're phasing them out is primarily because of maintenance issues and because there are more reliable and effective screening techniques," Harmon said.
At DIA, the work of one of the trace portals has been supplanted by a millimeter-wave whole-body imaging machine, she said, while two of the air-blowing portals still are being used.
"They are working and do have some security benefit," Harmon said, but they will gradually be phased out and replaced with other equipment.