There's a common answer that Mona Dohman, Minnesota's public safety commissioner, gets when she asks local law enforcement officers and firefighters what public threat intrudes on their thoughts late at night and leaves them tossing and turning with worry.

After an ominous fireball bloomed in the winter skies near Casselton, N.D., in late 2013, it should come as no surprise that oil transport accidents have public safety officials on edge in a state that is not only crisscrossed by oil pipelines but that has become a virtual freeway system for crude carried by rail out of western North Dakota's Bakken formation.

One of those trains derailed just outside of Casselton in December, causing an explosion and fire. While no one was injured, the accident and the plight of the Canadian town of Lac-Mégantic, where a fiery oil train derailment killed almost 50 people last summer, reinforced growing regional concerns about the sobering "what ifs" that come with being an oil transportation hub.

Minnesota legislators need to take these concerns seriously and do everything possible to ensure that communities along oil train routes and pipelines are fully prepared for potential disaster. That's why lawmakers hashing out a long-overdue update of the state's so-called "spill bill" — a 1991 law dealing with oil and chemical emergency preparedness — need to embrace the more comprehensive measures passed by the House.

Conference committee members are expected on Wednesday to dig in on bridging the differences between the strong House version and the curiously watered-down measures passed by the Minnesota Senate. Those doing the critical work of finalizing this critical legislation should keep in mind that public safety is their top priority.

The agenda of industry special interests is not, but unfortunately that group's self-serving influence is glaringly obvious in the Senate's weaker bill. It looks as if pipeline industry lobbyists in particular got hold of the legislation and redacted unwanted references to this oil transport mode.

That's irresponsible in a state where an estimated 900,000 people live in areas through which existing oil pipelines pass and another major pipeline is in the works — Enbridge's $2.6 billion Sandpiper project, which will bring the Bakken's notoriously volatile crude through northern Minnesota. Current pipelines mainly transport the heavier crude from Canada's tar sands.

Leaving out pipelines in this legislative update also ignores Minnesota history. The original "spill bill" was enacted after a 1.7-million-gallon pipeline spill in Grand Rapids, Minn., in spring 1991 by a pipeline owned by the Lakehead pipeline company, which is now Enbridge. Another major pipeline spill occurred in 2002 in Cohasset, Minn. In 2007, a pipeline repair produced a fireball that killed two Enbridge workers.

Minnesota DFL Rep. Frank Hornstein, chair of the House Transportation Finance Committee, made good this session on his vow to push for stronger oil transportation safety measures. His advocacy played a key role in legislation passed by both chambers that would increase the number of state rail inspectors from one to three (with an option of adding another), funded through an industry assessment. Both chambers' legislation will also increase training for local fire departments. In addition, the legislation calls for a study that would assess rail crossings frequently used by oil trains and provide recommendations to improve them.

The House bill goes further, with provisions sensibly covering both pipelines and oil trains. It also sets benchmarks and time frames for the industry to provide expertise and equipment — such as monitors to assess toxic vapor in the air — when an accident occurs. Safety drill frequency is prescribed, and the state's Pollution Control Agency is also directed to assist communities and industry in disaster planning, as well as facilitate "mutual-aid arrangements" by industry to provide staffing, training and equipment for emergencies.

Both House and Senate lawmakers missed a chance to more forcefully encourage or even require this type of cooperative — one successful model exists in the metro.

The House bill recognizes that massive changes have taken place in Minnesota since the spill bill became a reality, with the state now being a vital global oil conduit. It also ensures that industry fairly shoulders its responsibilities. The amount of oil coursing through the state means this is no time for half measures. The conference committee needs to show Minnesotans it understands.