The first-ever radio frequency identity (RFID) privacy bill has been passed in the US State of Utah, intended to ensure consumer privacy as retail stores start tagging products.

The Radio Frequency Identification Right to Know Act is one of the first to be proposed, before the technology has even been introduced in most shops.

Although the Act is still to be approved by the State senate, it will fuel the growing industry debate across the globe about the limits of consumer privacy in relation to RFID.

Utah's bill is based on US legislation drafted by consumer privacy group Consumers Against Supermarket Privacy Invasion and Numbering, which argues that all tagged items in stores should be labelled as such.

In the UK, a range of retailers, including Tesco, Marks & Spencer and Selfridges, are currently conducting trials of the technology.

Speaking at a RFID conference last month, Tesco IT director Colin Cobain highlighted the problem of customer perception and privacy, which is believed to have driven the retailer's adoption of the 'radio barcode' brand.

'We're trying to make it simpler for customers to understand,' he said.

Dr Roger Till, a director at supply chain standards body e.centre, says the issue of traceability is not a new concern.

'However, RFID tags developed to EPCglobal standards cannot be used to store customer information and, given the short range of scanners, it would be nearly impossible to create a network big enough to trace people as they went about their business,' he said.