Hypothetical response

That company owns and operates a factory in Indiana that produces, among other things, toluene, a substance that may be toxic, depending on dosage.
Six months ago, Dave Marrone, a worker at the plant, complained to his supervisor that he smelled toluene fumes in the section of the plant in which he worked. His supervisor, noting that none of Mr. Marrone’s coworkers who worked in the vicinity had complained, initially declined to investigate. Mr. Marrone renewed his complaint to the supervisor a month later. Two weeks afterwards, the supervisor inspected the area and noticed that a pipe near Mr. Marrone’s workspace was, in fact, leaking a small amount of toluene. The supervisor, without notifying Mr. Marrone or his coworkers, immediately ordered tests to determine the toluene exposure dosages of workers in the vicinity but decided to take no other action until receiving the results of the test the following day. The tests were performed unbeknownst to any workers in the vicinity. The results of the tests indicated to the supervisor that the workers’ toluene exposures were in amounts he understood to be non-toxic. The supervisor took no additional action.
During the two weeks between the date Mr. Marrone renewed his complaint to his supervisor and the date the supervisor investigated, Mr. Marrone called OSHA to complain about possible toluene exposure and to request an inspection of the premises. OSHA inspectors began their investigation shortly after the supervisor had completed his investigation. Three weeks later, the OSHA inspectors declined to cite or otherwise sanction Bjornlund Petrochemicals.
Two weeks after OSHA completed its investigation, Bjornlund Petrochemicals lost a major client. The attendant loss in revenue caused the company’s management to order a reduction in staff at the premises where Mr. Marrone worked. Mr. Marrone’s supervisor was asked to pick two employees working beneath him for redundancy. He chose Mr. Marrone as one of the two, giving as his reason for the choice Mr. Marrone’s lack of seniority relative to the rest of the staff. In private after Mr. Marrone was laid off, the supervisor indicated to you and some of Mr. Marrone’s former coworkers that the real reason Mr. Marrone was laid off was because he was a “squeaky wheel.”
Discussion Points
What rights did Mr. Marrone and his coworkers enjoy as a result of working near toluene?
Did the supervisor violate any employee rights in the manner by which he conducted the investigation? If so, what should he have done or not done?
Suppose that Mr. Marrone, after his layoff, lodged a complaint with OSHA alleging that he was terminated for notifying OSHA of possible hazards in the workplace.
Describe OSHA’s investigation, including when it would begin, how it would be conducted, and what it would be likely to conclude.
Suppose also that the OSHA investigator ultimately recommends a finding that Mr. Marrone’s case has merit. How will OSHA proceed? What, if anything, is Bjornlund Petrochemicals’s recourse?
Please answer each question separately.