The key criteria for diagnosing an occupational disease are: (1) the clinical features must match what is known about the health effects of exposure to the agent, (2) there must be evidence of sufficient occupational exposure, and (3) the time between exposure and effects must align with the natural history of the disease. Additional considerations include ruling out differential diagnoses and retaining concepts of minimum exposure levels, durations, latent periods, and induction periods required for causation.