By Mark Kinver
Science and environment reporter, BBC News
The new carbon audit has been piloted by several UK businesses
A new standard that allows UK firms to measure the size of their goods' carbon footprints has been launched.
It is hoped the new audit will show customers how much CO2 has been emitted during the production, consumption and disposal of a range of products.
Some schemes that measure carbon emissions have been criticised in the past for being inconsistent, confusing or lacking transparency.
The system, known as PAS 2050, will be managed by BSI British Standards.
"PAS 2050 has been developed using BSI's rigorous consultation process, involving almost a thousand industry experts from within the UK and internationally," said Mike Low, director of BSI British Standards.
"The result is a robust framework within which businesses and public sector bodies will be able to assess the greenhouse gas emissions of their goods and services in a consistent manner."
Mr Low added that he hoped the new audit tool would be used by organisations of all sizes.
The precursor to PAS 2050 was initially launched in 2006 by the Carbon Trust, a government-funded organisation, in response to a growing number of consumers who wanted to know the size of products' carbon footprint.
Trials, involving companies such as Walkers and Boots, led to "carbon labels" appearing on some goods in April 2007.
Despite the issue creeping up the political agenda in recent years, a survey by the Trust in December found that just 1% of firms questioned knew the size of their operation's carbon footprint.
Carbon Trust chief executive Tom Delay said he hoped making the scheme publicly available would improve the situation.
"For the first time, businesses have a robust, consistent standard for measuring the carbon footprint of their goods and services," he observed.
"This… development will help businesses really understand the carbon impact of their products and to follow this up with tangible ways to cut carbon emissions across the supply chain."
The Department for Environment, Food and Rural Affairs (Defra) co-sponsored the scheme, and Environment Secretary Hilary Benn said he hoped firms would use the tool.
"Companies have said that they want to be able to count their carbon emissions in a better way, and we have responded to that," he added.
"Consumers want to know that emissions are being cut by businesses and this standard will help businesses do that."
Later this year, the Climate Change Bill is expected to become law and will commit future governments to reducing carbon emissions by 80% from 1990 levels by 2050.