Consumers are being warned there's a risk that their personal data could be scanned from the wireless chip technology used on their banking cards.

However, the companies that use RFID chips say personal information contained in those chips is safe.

It can happen in an instant. A man and woman bump into each other in a shopping mall parking lot. Pretty innocent, but that is all it takes to scan data off a wireless credit card.

The woman has a card reader in her purse; the man has a wireless credit card in his pocket.

"From that little bump, the scanner gives us credit card number and other data that is transferred to a computer and then to a machine that can make credit cards and a counterfeit card is produced," said Andrea Rock, who authored the Consumer Reports investigation into cards and especially the RFID chips.

While many cards use chip technology, only some use RFID chips. If you look at your credit or debit card you may see a small symbol that looks like half moon curving lines. This symbol is usually on the card if it is equipped with RFID technology. Your card might also say ‘PayPass'.

The Radio Frequency Identification Device is a tiny transmitter, which lets you swipe your card over a reader in order to pay a bill.

But anyone can buy the readers, modify them and start scanning cards – and consumers will never know.

More reports are questioning the security of RFID. At Cambridge University in England, researchers say the chip combined with a pin number can be bypassed.

The industry contends there are other security measures in place and this form of payment is as safe as any other. It adds that fraud rates are hitting near historic lows and since the cards were introduced in Canada there have been no reports of fraud using the scanners.

Mind you no one would know if the cards had been scanned.

Antonio Romeo of Ottawa's Oralogic company is the Canadian distributor for special foil-lined sleeves making it harder to scan data.

The U.S. government is using these sleeves when they send out new passports with RFID chips and require staff to use them for RFID cards used to access government buildings.

"We have them being used in all kinds of applications. We were first to the market and right now consumers don't know much about the issue," said Romeo.

Consumer Reports made a sleeve out of duct tape and tinfoil. They say it worked better than most products on the market.

Detective Glen Barry of the Ottawa police fraud squad says they are yet to investigate a case like this.

"With technology, it's out there and everybody uses it and the criminals will get the same kind of technology as the card companies use. That is a possibility, but we have not had a case involving this kind of stuff," he said.

Visa tells CTV Ottawa in an email statement: "While companies selling protective card covers potentially have a financial incentive to create fear, Visa does not believe the limited risks warrant any inconvenience or additional expense to the cardholder."

The police officer says you should still watch your card and watch your bills for any unexplained spending.

With a report from CTV Ottawa's Paul Brent