With a carbon cap and trade now a near certainty for the United States, investors are rushing to fund companies that will help create the market. A Sterling, VA company called Clear Standards is the latest, with $4 million for an inventory system corporations can use to track their greenhouse gas emissions.

Measuring emissions is becoming a more exacting science as companies like this one consolidate studies showing the environmental impact of thousands of different materials, products and activities. In time, certain measurements will become the accepted standards, which will likely coincide with several measurement startups becoming dominant players.

Planet Metrics was the most recent competitor to Clear Standards to get funded, in a $2.3 million round closed a couple weeks ago. There are also several others, though, including Carbonetworks, CarbonView and Eps.

Clear Standards claims to go a step beyond its peers, however, by also tracking energy and water usage, as well as waste recycling. It also benefits from having executives with experience at Oracle and Siebel Systems.

Novak Biddle Venture Partners and Kinetic Ventures led the round.