The correct option is (c).
Explanation
Industrial chimneys are vertical structures designed to vent hot flue gases or smoke from a boiler, stove, furnace, or fireplace to the outside atmosphere. Their height is a critical factor in the effective dispersion of pollutants.
- Statement 1 is Incorrect: Chimneys are exhaust systems designed to expel waste gases produced during combustion or industrial processes. They do not function as intake mechanisms to bring fresh air into the factory. Fresh air is typically introduced through separate ventilation systems, windows, or intake vents.
- Statement 2 is Correct: The primary purpose of a chimney is to transport pollutants away from the immediate vicinity of the source. By venting smoke and gases at a height, chimneys prevent these harmful substances from accumulating at ground level, thereby keeping them away from direct human inhalation in the immediate area.
- Statement 3 is Correct: Long or tall chimneys release smoke and gases high into the atmosphere. Releasing pollutants at a higher elevation allows for better dispersion and dilution by upper-level winds, reducing the concentration of pollutants settling in the local surrounding area.
Key Takeaway: Tall chimneys are used to disperse particulate matter and noxious gases high into the atmosphere to minimize local ground-level pollution; they are exhaust mechanisms, not intake systems.