Question 87Safety & Environmental - QMED

The correct answer is C) filling open circuit breathing systems. The "Grade D" air quality standard applies to compressed air used for filling open-circuit breathing systems, such as those used in SCUBA diving or other underwater operations. This standard ensures the air is free of contaminants and safe for human breathing. The other answer choices are incorrect because they do not involve the use of compressed air for human respiratory purposes. Option A is for air-powered pumps, option B is for high-pressure fluid accumulators, and option D is for bladder-type accumulators, none of which require the stringent "Grade D" air quality standard.