New Jersey has put its chemical processing plants--all 140 of them--on notice. Under a state order signed last fall, those facilities will have to outline their security weaknesses and report them to state officials. That makes the state, which is among a handful of states with the most potentially dangerous chemical sites, the first to change from a voluntary to mandatory reporting system.

New Jersey's plants must also detail a plan to address their weaknesses. Forty-three of those facilities--those where an accident or an attack would have the biggest impact--must examine the possibility of using safer materials and processes.

While the new measure aims at helping the state manage its homeland security vulnerabilities, the mandate was championed by environmental and labor advocates and community groups. It was, however, threatened almost as soon as it was announced.

One week after the rule was put in place, the U.S. Senate began to consider federal chemical plant security legislation that would have eviscerated the New Jersey regulations. The Senate bill, which was endorsed by the chemical industry, would have prohibited states from adopting standards more stringent than the national baseline. Within two weeks, however, the language of the bill was changed.

The revised Senate language likely will leave New Jersey's own regulations intact, and it could pave the way for other states to adopt similar standards for the nation's 15,000 chemical plants.