OKLAHOMA CITY--LSB Industries, Inc. (the “Company”) (NYSE: LXU) announced that its Pryor, OK Facility (“Pryor Facility”) was shut down on March 15, 2012 for unplanned maintenance. Plant personnel have identified excess heat in areas of a high temperature, large diameter pipe in the ammonia plant. As a precautionary measure, ammonia plant production has been shut down while the pipe is removed and the cause of the excess heat determined and repairs performed. Maintenance has also been undertaken at the urea plant at the Pryor Facility over the preceding two weeks. During this period, when the urea plant has been undergoing maintenance, the Pryor Facility has not produced urea ammonium nitrate (“UAN”) but has been producing and selling ammonia directly into the fertilizer market. The Company expects to resume ammonia and UAN production before March 31st. The Company plans to announce when ammonia and UAN production has resumed.

The Company estimates that the effect of the ammonia plant and the urea plant maintenance outages in March will result in approximately $4 million less operating income than otherwise would have been expected.

LSB is a manufacturing, marketing and engineering company. LSB's principal business activities consist of the manufacture and sale of commercial and residential climate control products, such as geothermal and water source heat pumps, hydronic fan coils, large custom air handlers, modular geothermal and other chiller systems, the manufacture and sale of chemical products for the industrial, mining and agricultural markets; and other activities.