FOM-10.7 Fleet Operations Manual
FOM
Gas Detection Instrument (Oil , MR Tankers) 		Doc No.: FOM 10.7
Revision: 02
Date: 12 Feb 2026
Issued by: DPA
Approved by: MD

Portable Gas Detection System - For Oil/MR Tankers

No. Items
Standard Outfit
4 Personal Multi Gas Detector (H2S, CO, O2, CO2,LEL) GX-2009A or equivalent
2 Portable Multi Gas Detector (%LEL, %VOL, O2, H2S,CO2, CO) GX-8000A or equivalent (C4H10 ie Butane) units
2 Gas detector pump (manually operated bellows pump) that draws a sample through the short-term tubes.
1 Closed gastight -gas sampling device – Able to fit on MMC / UTI vapor lock port (not for Asphalt)
Gas Detector Tubes for:
3 Sets
(10 tubes per set)		 Benzene (0.1 – 5 ppm)
High range H2S (100-2000 ppm) for crude tankers
1 Set each
(10 tubes per set)		 Mercaptans (0.1 – 8 ppm), Xylene(2-200 ppm), Toluene (1-100 ppm)
Gas detector tubes should be from same manufacturer as the gas detector pump.
1 set (10 tubes each set) Styrene (2-100 ppm): For MRs with Chemical notation

Note: - In case of measuring high range of HC Volume for long duration, suggest isolating the CO and VOC sensor. Dummy sensors/blanks can be purchased.
- On receipt of voyage orders, vessel to refer to the IBC code and / or SDS sheet of the cargo to confirm the toxicity nature of the cargo to be carried and appropriately, extra toxic gas detector tubes are to be requisitioned. Ship can order additional tubes if required due to special requirement of a cargo or charterer.
-In case any aromatic hydrocarbons or products containing them (in excess of 1% by volume) are carried, vapour detection tubes for such products should be on board.
- In case of toxic constituents of Inert Gas, ISGOTT 1.4.11.2 states that:
- The precautions to protect personnel against the toxic components of IG during tank entry are in section ISGOTT 11.1.6.12. However. they do not include requirements for directly measuring the concentration of the trace constituents of flue gas. This is because gas freeing the atmosphere of a cargo tank from a hydrocarbon gas concentration of about 2% by volume to 1% LFL, and until a steady 21% by volume oxygen reading is reached. is enough to dilute these toxic constituents to below their OEL-TWA
- If the vessel is fitted with a BWTS, then suitable gas detection equipment (For Ozone, Chlorine, Hydrogen etc.) as applicable for the type of BWTS should be provided.
- All above equipment should be calibrated as per marker's instructions including compliance with required intervals.

Spares to be Carried

Quantity Items
1 set Long Neoprene Sample Hoses for each unit, including manually operated bellow pumps (each set must be at least depth of tank + 10ft)
– may be reduced if instruments have same connections
2 Spare Respirator Bulbs (for manual units only)
2 Boxes Spare Filters for each unit
2 Set Calibration / Span Gases for each type of equipment (must include instructions, certificates and response curves)
1 Set Complete 100% spare sensor for personal Multi gas Detector( H2S,CO,CO2,O2,LEL)
1 Set Complete 100% spare sensor for Portable Multi gas Detector( H2S,CO,CO2,O2,LEL)
2 Sets Rechargeable batteries c/w multiple size charger unit (Alkaline batteries)