Pennsylvania’s environmental rule-making body approved major revisions to strengthen the state’s oil and gas regulations on Wednesday at the end of a heated three-hour meeting when critics of the rules called elements of the package illegal or unnecessary.

The state Department of Environmental Protection, which drafted the rules over five years, defended them throughout the meeting and advised the board against adopting 16 amendments that would have changed the regulations’ language or meaning. The Environmental Quality Board eventually voted 15-4 to adopt the rules as DEP proposed them.

“This is certainly a big milestone for work that is long overdue,” DEP Secretary John Quigley said after the vote. He called the rules package, which lays out separate standards for the state’s shale gas and traditional shallow oil and gas drilling industries, “a set of reasonable, balanced and incremental improvements.”

The 20-member Environmental Quality Board is made up of the heads of state agencies, members of the state Senate and House, and representatives of a citizens advisory council.

Although DEP crafts environmental rules, it is ultimately the board that adopts them before they go on for further review by legislative committees and an independent state regulatory review agency.

The updates to the rules are wide-ranging, with a particular focus on adding protections for public resources that might be disrupted by drilling, ensuring that new wells don’t intersect with abandoned ones, setting stricter standards for waste handling and cleanup, and requiring that damaged drinking water supplies are restored to a safe quality or better.

Critics said DEP did not follow laws directing the rule-making process precisely and disregarded concerns from its industry-led advisory committees. The state’s Office of General Counsel reviewed the rules to make sure they were legal and recommended that they move forward, but the regulations are likely to be challenged in court by oil and gas industry groups.

“You’re being asked to ignore your statutory duty, to break the law about how regulations are written and adopted,” Rep. John Maher, R-Upper St. Clair, said as he urged the board to reject the rules after he tried unsuccessfully to amend them.

Sen. Gene Yaw, R-Lycoming, said the environmental agency had not made the case that there was a compelling interest for the changes. “Some of these, they’re regulations looking for a problem,” he said.

Mr. Yaw and Mr. Maher lead the General Assembly’s environmental resource and energy committees, so they will have another chance to review the rules before they take effect.

DEP has estimated that the updated regulations will be published and enforceable by this summer.