Carbon Monoxide in Cargo Spaces

Carbon monoxide is generated in a cargo space by the oxidation of organic material, principally forest products, and it is the gas that has caused most of the documented enclosed-space fatalities on solid bulk cargoes. It has a relative density of 0.97, so it is very slightly lighter than air and distributes through a space rather than pooling at one level.

The full article will cover which IMSBC cargoes generate it and at what rate, the concentrations actually measured on ships, the detection problem created by instruments whose range stops short of the levels present, and why an oxygen reading is not a proxy: MSC.581(110) Appendix 5 records that oxygen may still read 17 to 14 percent when carbon monoxide has reached 1,200 ppm.

It will also set out the exposure limits by issuing body, since there is no global figure. The European Union indicative limit is 20 ppm over eight hours, the ACGIH threshold limit value is 25 ppm, the NIOSH recommended limit and the IMO reference figure are 35 ppm, and the United States OSHA permissible exposure limit is 50 ppm.