Gas Detection Instrument (Gas Tankers)


FOM-10.9	Fleet Operations Manual FOM Gas Detection Instrument (Gas Tankers)	Doc No.: FOM 10.9 Revision: 02 Date: 12 Feb 2026 Issued by: DPA Approved by: MD

Portable Gas Detection System - Gas 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 (Butane unit) or equivalent
2	Gas detector pump (manually operated bellows pump) that draws a sample through the short-term tubes.
Gas Detector Tubes
3 Sets (10 tubes per set)	Benzene (0.1 – 65 ppm)
1 Set (10 tubes per set)	Gas detector tubes for: Mercaptans (0.1 – 8 ppm) Butadiene (2.5 – 100ppm) if applicable Gas detector tubes should be from same manufacturer as the gas detector pump.
1 set (10 tubes per set)	Special requirement for Ethylene ships Ethylene (0.2 to 50ppm) Acetylene (0.1 to 2.0 %) Special requirement for ships carrying toxic cargoes or aromatic hydrocarbons Ethylene Oxide 163L (1 - 100ppm) and 163LL (0.1 - 5ppm) Propylene Oxide 163L (1 - 100ppm) and 163LL (0.1- 5ppm) Propylene - LP-Gas 100A (0.02 - 0.8 %) Vinyl chloride 131L (0.2 - 3ppm) & 131LB (1 - 20 ppm) *Note: Ensure the above tubes are onboard prior to loading of the cargo.*

In case of measuring high range of HC Volume for long duration, suggest to isolate the CO and VOC sensor. Dummy sensors/blanks can be purchased.
On receipt of voyage orders, vessel to refer to the IGC 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.

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 Sets	Calibration / Span Gases for each type of equipment (must include instructions, certificates and response curves)
1 Sets	Complete 100% spare sensor for personal Multi gas Detector( H2S,CO,CO2,O2,LEL)
1 Sets	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)