Table 2.

Description of activities on vessels that supported the oil spill clean-up operations.

Vessel activity (/water indicates the activity was on the water in contrast to a similar activity done on land)	Descriptiona
Transport vessel	Vessel carried food, water, supplies, passengers, and other essential items throughout the Gulf of Mexico to and from shore.
Vessel burned oil	Vessels involved in burning oil on the water surface. The oil was ignited after being contained by fire boom pulled by fishing vessels. Primarily done offshore.
Vessel scouted for oil/wildlife on water	Vessel drove around the Gulf waters looking for oil to be burned or skimmed by other groups. Oiled wildlife (either alive or dead) were reported or captured and taken to shore.
Vessel put out, inspected, moved, or collected booms or absorbent	Boom and absorbents were used to contain the oil. These vessels put them out, inspected them to make sure they continued to be effective, moved them to increase effectiveness and collected them when the boom and absorbents was no longer needed. Could have been done offshore to support in situ burning or skimming or nearer to shore to protect shorelines.
Vessel handled oily booms and absorbents	A group developed for subjects in the GuLF STUDY questionnaire who indicated their vessel did not put out (clean) boom or absorbents (versus ‘Vessel put out, inspected, moved, or collected booms or absorbent’).
Vessel deconned other vessels/ water	<?formattrackingstart -5?>Gross decontamination of the vessel’s (primarily) outside done to reduce the amount of oil dragged into the ports and docks. This was done primarily with pressure spraying with workers in boats off the side. Generally done near shore, although some stations were offshore.<?formattrackingend -5?>
Vessel patrolled beaches/marshes for oil/tar/animal	Vessel drove around looking for oil to be captured by other groups. Oiled wildlife (either alive or dead) were reported or captured and taken to shore. Near shore.
Worked on a boat or ship	A group developed for subjects who did not identify in the GuLF STUDY questionnaire any of the water activities. No information as to where these participants may have been.
Barge work	Barges carried recovered oil from the hot zone or oil/oily water skimmed from offshore and clean or decontaminated equipment from land to various locations in the Gulf and back.
Research vessels	Research vessels under the auspices of the NOAA, universities, or other research organizations tasked with collecting air, water, sediments, subsurface oil, and dispersants and fish samples. N = 33. These were larger vessels with greater resources than the fishing vessels assigned to ‘Environmental sampling/water/non-NOAA’. These worked throughout the Gulf.
Vessel sprayed dispersant on surface	Vessel sprayed dispersant on the water surface to reduce the oil vapors. Only in the hot zone and source.
Environmental sampling/water/non-NOAA	Developed for study subjects who indicated in the GuLF STUDY questionnaire that they took collected samples but who appeared to have worked on a small, privately owned fishing vessel. No information on the location in the Gulf.
Handled hazardous waste/water	Vessel handled hazardous waste, including contaminated equipment, such as oiled boom. This may have been done throughout the Gulf waters, but primarily closer to shore.
Draft/air/jon boat	Small boats that traveled the coastline looking for oil or wildlife or transporting personnel to nearby islands. May have skimmed.
Vessel skimmed and personally skimmed	Large or small vessels using mechanical devices, nets, and absorbents to collect the oil. Includes the general crew and the specific workers who operated the skimming equipment.
Deconned all/water	A group developed for subjects who reported in the GuLF STUDY questionnaire deconning all equipment, i.e. vessels, boom, and any other equipment that needed cleaning. Cleaning was done primarily with pressure spraying but could have included absorbents. Most of the work would have been the hulls of vessels.
Vessel deconned and personally deconned/water	A group developed for subjects who reported in the GuLF STUDY questionnaire actually doing the deconning on a vessel that deconned other vessels/water. See ‘Vessel deconned other vessels/water’.
Vessel carried oil/oily water	Vessels included barges and cargo ships that carried oil and oily water from the recovered oil in the hot zone and from skimming operations to shore.
Vessel handled oily boom and absorbents and personally handled oily boom	A group developed for subjects who reported in the GuLF STUDY questionnaire actually handling boom or absorbents. See ‘Vessel handled oily booms and absorbents’.
IH/safety-water	Industrial hygienists, safety professionals and medics monitored air concentrations and ensured the safety of the workers.
On vessel while being deconned/water	A group developed for subjects who reported in the GuLF STUDY questionnaire staying on a vessel as it was being decontaminated on the water. See ‘Vessel deconned other vessels/water’.
Cleaned oil pools	As an unintended consequence of many of the tasks, oil collected on the deck of the vessels. Clean-up was done by wiping it up with absorbents.
Maintained pumps/tanks or dis/connected anything (inc oil)/water	Tasks performed on the barges, cargo ships, and skimming vessels generally in the transfer or oil or oily water. Could have occurred throughout the Gulf.
Areas on the Gulf: Developed because workers in the different Gulf areas were found to have statistically different AMs and a question was not asked of each subject where they performed each of their reported activities.
Offshore	A group developed to reflect study subjects’ higher exposure levels than levels near shore due to the proximity to the hot zone and source.
Vessel could see shoreline (near shore)	A group developed to reflect study subjects’ lower exposure levels than offshore or the source/hot zone areas due to the greater distance from the wellhead.
Could see wellhead from vessel	A group developed to reflect the highest exposures study subjects may have experienced due to their proximity to the wellhead.

^a Each activity includes all workers on the vessel indoors or out of doors and whether the worker is a crew member or performing the actual work, unless specified (i.e. ‘personally…’). See text for more details.