Question 2904 Deck General

The correct answer is B) 50 parts per million (ppm). When H2S has been encountered on a MODU (Mobile Offshore Drilling Unit), or is anticipated, monitoring devices must sound an alarm or otherwise warn employees when the concentration of H2S reaches or exceeds 50 ppm. This is in accordance with the OSHA (Occupational Safety and Health Administration) standard for H2S exposure in the oil and gas industry. The other answer choices are incorrect because 20 ppm is the lower concentration alarm threshold, while 100 ppm and 200 ppm are higher than the required 50 ppm warning level specified in the regulation.