BP, the company in charge of the rig that exploded last month in the Gulf of Mexico, hasn't publicly divulged the results of tests on the extent of workers' exposure to evaporating oil or from the burning of crude over the gulf, even though researchers say those data are crucial in determining whether the conditions are safe. Moreover, the company isn't monitoring the extent of the spill and only reluctantly released videos of the spill site that could give scientists a clue to the amount of the oil in the gulf. BP's role as the primary source of information has raised questions about whether the government should intervene to gather such data and to publicize them and whether an adequate cleanup can be accomplished without the details of crude oil spreading across the gulf. The company also hasn't publicly released air sampling for oil spill workers although Occupational Safety and Health Administration, the agency in charge of monitoring compliance with worker safety regulations, is relying on the information and has urged it to do so.