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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Minimum duration of developing coal miners pneumoconiosis is -
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The correct answer is  - The coal miners pneumoconiosis has two phases; first phase is simple pneumoconiosis which is associated with little ventilatory impairment. - this phase may require about 12 years of work exposure for its development. - second phase is characterized by progressive massive fibrosis Reference: Park's textbook of preventive and social medicine, 23rd edition, pg no:806 <\p>