HARRISBURG — Pennsylvania will join other major natural-gas states in requiring the prompt disclosure of production results.

State senators unanimously approved the measure Tuesday, six days after the House did the same. Gov. Ed Rendell is expected to sign it.

State legislators are peeling back the cloak of secrecy just as exploration companies are flocking to Pennsylvania in pursuit of natural gas in the sprawling Marcellus Shale formation.

The measure will require the disclosure of well-specific production data every six months. Currently, a 25-year-old state law requires state regulators to keep oil and gas production data confidential for five years.

Supporters say faster disclosure will help companies harvest gas and let landowners see if they are getting the royalties they are owed.