Precautions for H2S should be taken when?
Direct Answer
Option B: More than 5 ppm in Volume
Precautions for hydrogen sulphide (H2S) must be taken when concentrations exceed 5 ppm in volume. This level represents the Threshold Limit Value – Time Weighted Average (TLV-TWA) for an 8-hour exposure, as stipulated by occupational safety guidelines and ISGOTT.
All Options
Detailed Explanation & Context
Precautions for hydrogen sulphide (H2S) must be taken when concentrations exceed 5 ppm in volume. This level represents the Threshold Limit Value – Time Weighted Average (TLV-TWA) for an 8-hour exposure, as stipulated by occupational safety guidelines and ISGOTT.
Relevant Framework: STCW 2010 Manila Amendments • DG Shipping E-Learning & Exit Exam Standards • Advanced Training for Chemical Tanker Cargo Operations (CHEMCO).
Practice Full CHEMCO Set 10
Test yourself with 30 interactive questions, live timer, and instant score.