Shell (D) incurred liability when a catalytic cracking unit exploded. A class action was initiated to recover for all the damages incurred from the explosion. A Plaintiff's Legal Committee (P) and its experts were given access to the CCU unit to inspect, measure, and photograph. D preserved all materials tagged by P as well as additional materials D wanted preserved. D conducted metallurgical and chemical tests on material removed from the site. Nordstrom and Nelson were two of D's employees who were present during the testing. P experts also observed certain tests. Three months after the explosion the court ordered all experts who visited the plant and who will be experts at trial must submit a preliminary report to the court. D submitted five reports. Reports were not exchanged until seven months later. P filed several discovery requests seeking expert discovery from D. The court ruled against discovery unless D intended to use the expert at trial. P filed a motion for reconsideration in August 1989 seeking the results of tests on CCU material. D opposed the motion in that it had not yet decided which test results and experts it intended to use at trial. D also states that it will not call Nordstrom or Nelson or use their preliminary expert reports.