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Suggested Citation:"Glossary." National Research Council. 2007. Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants: Volume 1. Washington, DC: The National Academies Press. doi: 10.17226/11170.
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Glossary

Accommodation: The act or state of adjustment or adaptation.1

ACGIH (American Conference of Governmental Industrial Hygienists): ACGIH is a member-based organization and community of professionals that advances worker health and safety through education and the development and dissemination of scientific and technical knowledge. ACGIH publishes exposure guidance values called Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs). Exposures at or below TLVs or BEIs do not create an unreasonable risk of disease or injury. TLVs and BEIs are designed for use by industrial hygienists in making decisions regarding safe levels of exposure to various chemical substances and physical agents found in the workplace.2

Acute exposure: An exposure lasting 1 day or less.3

Acute exposure guideline levels (AEGLs): AEGLs “represent threshold exposure limits for the general public and are applicable to emergency exposures ranging from 10 min to 8 h. Three levels—AEGL-1, AEGL-2, and AEGL-3—are developed for each of five exposure periods (10 min, 30 min, and 1 h, 4 h, and 8 h) and are distinguished by varying degrees of severity of toxic effects. AEGL-1 is the airborne concentration of a substance above which it is predicted that the general population, including susceptible individuals, could experience notable discomfort, irritation, or certain asymptomatic nonsensory effects. However, the effects are not disabling and are transient and reversible upon cessation of exposure. AEGL-2 is the airborne concentration of a substance above which it is predicted that the general population, including susceptible individuals, could experience irreversible or other serious, long-lasting adverse health effects or an impaired ability to escape. AEGL-3 is the airborne concentration above which it is predicted that the general

Suggested Citation:"Glossary." National Research Council. 2007. Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants: Volume 1. Washington, DC: The National Academies Press. doi: 10.17226/11170.
×

population, including susceptible individuals, could experience life-threatening health effects or death.”4

Adaptation: The acquisition of modifications that fit a plant or animal to life in a new environment or under new conditions.1

AEGL:See acute exposure guideline levels.

Aerosol: A suspension of liquid or solid particles in a gas.5

Alveolar macrophage: A mononuclear phagocytic cell arising from monocytic stem cells in bone marrow whose function is to ingest and digest foreign matter in the alveoli.1

Area under the curve (AUC): A measure of exposure that includes both duration and concentration. It is calculated from the curve that results when the concentrations of the test substance in some biologic tissue, typically blood, are plotted versus the exposure time.

ATA:See atmosphere absolute.

Atmosphere absolute (ATA): One atmosphere absolute (1-ATA) is the average atmospheric pressure exerted at sea level, 14.7 pounds per square inch (psi). Two-atmosphere absolute (2-ATA) is twice the atmospheric pressure exerted at sea level. If a physician prescribes 1 hour of hyperbaric oxygen treatment at 2-ATA, the patient breathes 100% oxygen at two times the atmospheric pressure at sea level for 1 hour.

ATSDR (Agency for Toxic Substances and Disease Registry): The ATSDR is an agency of the Department of Health and Human Services that was created by Congress under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA), commonly known as the Superfund Act. Its mission is to serve the public by using the best science, taking responsive public health actions, and providing trusted health information to prevent harmful exposures and disease related to toxic substances. ATSDR defines minimal risk levels (MRLs).6

AUC: See area under the curve.

CAMS:See central atmosphere monitoring system.

CDC (Centers for Disease Control and Prevention): The CDC is an agency of the Department of Health and Human Services. The CDC promotes health and quality of life by preventing and controlling disease, injury, and disability. The National Institute of Occupational Safety and Health (NIOSH) is part of the CDC.7

CEGL:See continuous exposure guidance level.

Ceiling concentration: A concentration that shall not be exceeded during any part of a working exposure.8

Suggested Citation:"Glossary." National Research Council. 2007. Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants: Volume 1. Washington, DC: The National Academies Press. doi: 10.17226/11170.
×

Central atmosphere monitoring system (CAMS): CAMS monitors the submarine atmosphere by using “an infrared spectrometer to measure carbon monoxide and a mass spectrometer to measure oxygen, nitrogen, carbon dioxide, hydrogen, water vapor, and fluorocarbons 11, 12, and 114.”9

Chronic exposure. An exposure lasting 6-24 months.3

Chronic obstructive pulmonary disease (COPD): COPD is “a disease characterized by chronic bronchitis or emphysema and airflow obstruction that is generally progressive, maybe accompanied by airway hyperreactivity, and may be partially reversible.”10

Continuous exposure guidance level (CEGL): A CEGL is defined as a ceiling concentration designed to prevent any immediate or delayed adverse health effect or degradation in crew performance resulting from a continuous exposure lasting up to 90 days.

CO: Carbon monoxide.

CO2: Carbon dioxide.

COPD:See chronic obstructive pulmonary disease.

Draeger tube: A monitoring device for acetone, ammonia, benzene, CO, CO2, chlorine, hydrazine, hydrochloric acid, NO2, ozone, sulfur dioxide, toluene, total hydrocarbons, methyl chloroform, and monoethanolamine.11

EEGL: See emergency exposure guidance level.

Electrostatic precipitator: A system to clear particles and aerosols from air.12

Emergency exposure guidance level (EEGL): An EEGL is defined as a ceiling concentration that will not cause irreversible harm or prevent performance of essential tasks, such as closing a hatch or using a fire extinguisher, during a rare emergency situation lasting 1-24 hours.

EPA: U.S. Environmental Protection Agency.

FEV1:See forced expiratory volume.

Forced expiratory volume (FEV1). FEV1 is a standard test of lung function. It is the volume of air that can be forcibly exhaled in 1 second following a maximal inspiration.11

Forced vital capacity (FVC): FVC is a standard test of lung function. It is the maximal volume of air that can be exhaled as forcibly and rapidly as possible after a maximal inspiration.11

Fumes: Particulate, smoke-like emanations from the surface of heated metals.6

FVC:See forced vital capacity.

Suggested Citation:"Glossary." National Research Council. 2007. Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants: Volume 1. Washington, DC: The National Academies Press. doi: 10.17226/11170.
×

Gas: One of the three states of matter, characterized by very low density and viscosity (relative to liquids and solids); comparatively great expansion and contraction with changes in pressure and temperature; ability to diffuse readily into other gases; and ability to occupy with almost complete uniformity the whole of any container.6

H2: Hydrogen.

Habituation: Decreased responsiveness to stimulation.12

IARC (International Agency for Research on Cancer): IARC is an agency of the World Health Organization. IARC’s carcinogenicity classifications are as follows:13

Group 1. The agent (mixture) is carcinogenic to humans. The exposure circumstance entails exposures that are carcinogenic to humans.

Group 2A. The agent (mixture) is probably carcinogenic to humans. The exposure circumstance entails exposures that are probably carcinogenic to humans.

Group 2B. The agent (mixture) is possibly carcinogenic to humans. The exposure circumstance entails exposures that are possibly carcinogenic to humans.

Group 3. The agent (mixture, or exposure circumstance) is not classifiable as to carcinogenicity in humans.

Group 4. The agent (mixture, exposure circumstance) is probably not carcinogenic to humans.

Irritant: A toxicant that exerts its deleterious effects by causing inflammation of mucous membranes on contact. Irritants principally act on the respiratory system and can cause death from asphyxiation due to lung edema.14

Irreversible harm: Permanent damage or injury to health. Emergency exposure guidance levels (EEGLs) are designed to avoid or prevent irreversible harm.

LC01: Lethal concentration in 1% of the sample population.

LC50: Lethal concentration in 50% of the sample population.

LOAEL:See lowest-observed-adverse-effect level.

Lowest effect level: The lowest dose or exposure level in a study at which a statistically or biologically significant effect is observed in the exposed population compared with an appropriate unexposed control group.15

Lowest-observed-adverse-effect level (LOAEL): A LOAEL is the “lowest exposure level at which there are statistically or biologically significant increases in frequency or severity of adverse effects between the exposed population and its appropriate control group.”16

MEA: Monoethanolamine.

Suggested Citation:"Glossary." National Research Council. 2007. Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants: Volume 1. Washington, DC: The National Academies Press. doi: 10.17226/11170.
×

Minimal risk level (MRL): ATSDR’s “estimate of daily human exposure to a hazardous substance at or below which that substance is unlikely to pose a measurable risk of harmful (adverse), noncancerous effects. MRLs are calculated for a route of exposure (inhalation or oral) over a specified time period (acute, intermediate, or chronic).”17

MRL:See minimal risk level.

NAAQS:See national ambient air quality standards.

National ambient air quality standards (NAAQS): “The Clean Air Act, requires EPA to set National Ambient Air Quality Standards (NAAQS) for pollutants considered harmful to public health and the environment. The Clean Air Act established two types of national air quality standards. Primary standards set limits to protect public health, including the health of ‘sensitive’ populations such as asthmatics, children, and the elderly. Secondary standards set limits to protect public welfare, including protection against decreased visibility, damage to animals, crops, vegetation, and buildings. NAAQS have been set for six principal pollutants, which are called ‘criteria’ pollutants: carbon monoxide, nitrogen dioxide, ozone, lead, particulate matter, and sulfur dioxide.”18

NH3: Ammonia.

NIOSH: National Institute for Occupational Safety and Health.

NO: Nitric oxide.

NO2: Nitrogen dioxide.

NOAEL:See no-observed-adverse-effect level.

NOEL.See no-observed-effect level.

No-observed-adverse-effect level (NOAEL): A NOAEL is “an exposure level at which there are no statistically or biologically significant increases in the frequency or severity of adverse effects between the exposed population and its appropriate control; some effects may be produced at this level, but they are not considered as adverse, nor precursors to specific adverse effects. In an experiment with several NOAELs, the regulatory focus is primarily on the highest one leading to the common usage of the term NOAEL as the highest exposure without adverse effect.”17

No-observed-effect level (NOEL): A NOEL is the “greatest concentration or amount of a substance, found by experiment or observation, that causes no alterations of morphology, functional capacity, growth, development, or life span of target organisms distinguishable from those observed in normal (control) organisms of the same species and strain under the same defined conditions of exposure.”19

Suggested Citation:"Glossary." National Research Council. 2007. Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants: Volume 1. Washington, DC: The National Academies Press. doi: 10.17226/11170.
×

OSHA (Occupational Safety and Health Administration): OSHA is an agency of the U.S. Department of Labor. It is authorized to set workplace health and safety standards for a wide variety of physical and chemical hazards and occupational situations. OSHA establishes permissible exposure limits (PELs) for a typical 8-hour workday within a 40-hour workweek and short-term exposure limits (STELs) applicable to a 15-min period within a workday.20

PEL:See permissible exposure limit.

PEL-TWA:See permissible exposure limit.

Permissible exposure limit (PEL): A PEL is the “maximum amount or concentration of a chemical that a worker may be exposed to under OSHA regulations.”21 According to OSHA regulations, the permissible exposure limit–time-weighted average (PEL-TWA) is a regulatory standard for a particular chemical expressed as “an average value of exposure over the course of an 8 hour work shift.”22

RD50: A statistically estimated concentration resulting in 50% reduction in respiratory rate.

Recommended exposure limit (REL): A REL is “an 8- or 10-h time-weighted average (TWA) or ceiling concentration recommended by NIOSH that is based on an evaluation of the health effects data.”22

Reference concentration (RfC): EPA’s estimate of “air exposure concentration to the human population (including sensitive subgroups) that is likely to be without appreciable risk of deleterious effects during a life-time.”23

REL:See recommended exposure limit.

Relative risk (RR): RR is an epidemiologic measure of association between an exposure or risk factor and disease incidence. It is expressed as a ratio of the incidence rate for exposed persons to the incidence rate for the unexposed.24

Reversible effect: An injury from which a target tissue or organ can recover or regenerate.

RfC:See reference concentration.

RR:See relative risk.

SEAL:See submarine escape action levels.

Short-term exposure limit (STEL): As defined by ACGIH, a STEL is a “15-minute TWA exposure for a regulated chemical that should not be exceeded at any time during a workday, even if the 8-hour TWA is within the TLV-TWA or PEL-TWA.”22

Suggested Citation:"Glossary." National Research Council. 2007. Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants: Volume 1. Washington, DC: The National Academies Press. doi: 10.17226/11170.
×

Short-term public emergency guidance levels (SPEGLs): SPEGLs are “suitable concentrations for single, short-term, emergency exposures, of the general public.”25

SMAC:See spacecraft maximum allowable concentrations.

Spacecraft maximum allowable concentrations (SMACs): SMACs are “concentrations of airborne substances (such as gas, vapor, or aerosol) that will not compromise the performance of specific tasks during emergency conditions. Exposure to 24-h SMACs will not cause serious or permanent effects but may cause reversible effects that do not impair judgment or interfere with proper responses to emergencies such as fires or accidental releases. Long-term SMACs (e.g., 7 day) are intended to avoid adverse health effects (either immediate or delayed) and to avoid degradation in crew performance with continuous exposure in a closed space-station environment. SMACs were developed for astronauts (healthy individuals).”26

SMR:See standardized mortality ratio.

SPEGL:See short-term public emergency guidance levels.

SSBN: Nuclear-powered ballistic missile submarines, Ohio class.

SSN: Nuclear-powered attack submarines. There are three SSN classes: Los Angeles, Seawolf, and Virginia.

Standardized mortality ratio (SMR): SMR is a measure of population health. It is calculated by taking the ratio of the number of deaths observed in the population of interest to the number of deaths expected on the basis of the mortality rates of a reference population.24

STEL: See short-term exposure limit.

Subchronic exposure: An exposure lasting 2-13 weeks or 10% of the test animal life-span.3

Submarine escape action levels (SEALs): At concentrations below a SEAL 1, respiratory and central nervous system function should not be impaired enough to significantly affect the ability to escape or to be rescued, and crew members can remain in the submarine without wearing eye and respiratory protection (EABs) for up to 10 days. At and above SEAL 1, but below SEAL 2, respiratory and central nervous system effects should not be severe enough to hamper ability to escape, and crew members would not be required to wear EABs but would plan to escape so that the last man leaves the submarine within 24 h. At and above a SEAL 2, unprotected exposure to the gas can result in impairment to respiratory and central nervous system function to an extent that the ability to escape would be compromised, and crew members should be required to wear EABs.9

Suggested Citation:"Glossary." National Research Council. 2007. Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants: Volume 1. Washington, DC: The National Academies Press. doi: 10.17226/11170.
×

Threshold Limit Value (TLV): A TLV is the “concentration in air of a substance to which it is believed that most workers can be exposed daily without adverse effect (the threshold between safe and dangerous concentrations). These values are established (and revised annually) by the American Conference of Governmental Industrial Hygienists and are time-weighted concentrations for a 7- or 8-hour workday and a 40-hour workweek.”20

Time-weighted average (TWA): Under OSHA regulations, a TWA is the average concentration of a regulated chemical to which a worker may be repeatedly exposed during a conventional 8-h workday and a 40-h workweek without adverse effect.

TLV:See Threshold Limit Value.

TWA:See time-weighted average.

UF:See uncertainty factor.

Uncertainty factor (UF): A UF (e.g., 1, 2, 3, or 10) can be used when deriving human health risk reference values from experimental data to account for inter- or intraspecies differences, database gaps, extrapolations from high to low dose, or other adjustments required. Multiple UFs can be used in a calculation. A UF of 10 is considered to be a health-protective default value to be employed when little is known about a particular source of variability or uncertainty, such as intraspecies differences or lack of information on a relevant health effect. As additional research becomes available, UFs change as indicated by the new information.

Vent fog precipitator: A system used in the submarine engine room to clear the air of oil mists.

VOC: See volatile organic compounds.

Volatile organic compounds (VOCs): VOCs are organic chemicals that have high vapor pressure and easily form vapors at normal temperature and pressure.

NOTES

  

1. Stedman, L.S. 1982. Stedman’s Medical Dictionary, 24th Ed. Baltimore, MD: Williams and Wilkins.

  

2. See http://www.acgih.org for more information.

  

3. Auletta, C.S. 1995. Acute, subchronic, and chronic toxicology. Pp. 69-127 in CRC Handbook of Toxicology, M.J. Derelanko and M.A. Hollinger, eds. Boca Raton: CRC Press.

Suggested Citation:"Glossary." National Research Council. 2007. Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants: Volume 1. Washington, DC: The National Academies Press. doi: 10.17226/11170.
×

  

  

4. NRC (National Research Council). 2001. Standing Operating Procedures for Developing Acute Exposure Guideline Levels for Hazardous Chemicals. Washington, DC: National Academy Press.

  

5. Hawley, G.G. 1977. The Condensed Chemical Dictionary, 9th Ed. New York: Van Nostrand Reinhold Company.

  

6. See http://www.atsdr.cdc.gov/ for more information.

  

7. See http://www.cdc.gov/ for more information.

  

8. NRC (National Research Council). 2002. Review of Submarine Escape Action Levels for Selected Chemicals. Washington, DC: National Academy Press.

  

9. NRC (National Research Council). 1988. Submarine Air Quality. Washington, DC: National Academy Press.

  

10. Beers, M.H., and R. Berkow, eds. 1999. The Merck Manual of Diagnosis and Therapy, 17th Ed. Whitehouse Station, NJ: Merck Research Laboratories.

  

11. Hagar, R. 2003. Submarime Atmosphere Control and Monitoring Brief for the COT Committee. Presentation at the First Meeting on Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants. January 23, 2003, Washington, DC.

  

12. Miller, D.B., and D.A. Eckerman. 1986. Learning and memory measures. Pp. 94-149 in Neurobehavioral Toxicology, Z. Annau, ed. Baltimore, MD: The Johns Hopkins University Press.

  

13. See http://www.iarc.fr/pageroot/GENERAL/indexgen.html for more information.

  

14. Hodgson, E., R.B. Mailman, and J.E. Chambers, eds. 1988. Dictionary of Toxicology. New York: Van Nostrand Reinhold Company.

  

15. EPA (U.S. Environmental Protection Agency). Glossary of IRIS terms. Integrated Risk Information System, U.S. Environmental Protection Agency. [Online]. Available: http://www.epa.gov/iris/gloss8.htm.

  

16. NRC (National Research Council). 2000. Toxicological Effects of Methyl-mercury. Washington, DC: National Academy Press.

  

17. ATSDR (Agency for Toxic Substances and Disease Registry). 2003. ATSDR Glossary of Terms [Online]. Available: http:// www.atsdr.cdc.gov/glossary.htm.

  

18. EPA (U.S. Environmental Protection Agency). 2003. National Ambient Air Quality Standards (NAAQS). Office of Air and Radiation, U.S. Environmental Protection Agency. [Online]. Available: http://www.epa.gov/air/criteria.html.

  

19. IUPAC (International Union of Pure and Applied Chemistry). 1993. Glossary for chemists of terms used in toxicology. Pure Appl. Chem. 65(9):2003-2122. [Online]. Available: http://www.sis.nlm.nih.gov/Glossary/main.htm.

  

20. See http://www.osha.gov/ for more information.

  

21. 29 CFR 1910.1200.

  

22. NIOSH (National Institute for Occupational Safety and Health). 2003. NIOSH Pocket Guide to Chemical Hazards. [Online]. Available: http://www.cdc.gov/niosh/npg/pgintrod/html.

  

23. EPA (U.S. Environmental Protection Agency). 1989. Glossary of Terms Related to Health, Exposure, and Risk Assessment. EPA/450/3-88/016. Air Risk Information Support Center, U.S. Environmental Protection Agency, Washington, DC.

Suggested Citation:"Glossary." National Research Council. 2007. Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants: Volume 1. Washington, DC: The National Academies Press. doi: 10.17226/11170.
×

  

  

24. Mausner, J.S., S. Kramer, and A.K. Bahn. 1985. Epidemiology: An Introductory Text, 2nd Ed. Philadelphia: W.B. Saunders Company.

  

25. NRC (National Research Council). 1986. Criteria and Methods for Preparing Emergency Exposure Guidance Level (EEGL), Short-Term Public Emergency Guidance Level (SPEGL), and Continuous Exposure Guidance Level (CEGL) Documents. Washington, DC: National Academy Press.

  

26. NRC (National Research Council). 1994. Spacecraft Maximum Allowable Concentrations for Selected Airborne Contaminants, Vol. 1. Washington, DC: National Academy Press.

Suggested Citation:"Glossary." National Research Council. 2007. Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants: Volume 1. Washington, DC: The National Academies Press. doi: 10.17226/11170.
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Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants: Volume 1 Get This Book
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U.S. Navy personnel who work on submarines are in an enclosed and isolated environment for days or weeks at a time when at sea. Unlike a typical work environment, they are potentially exposed to air contaminants 24 hours a day. To protect workers from potential adverse health effects due to those conditions, the U.S. Navy has established exposure guidance levels for a number of contaminants. The Navy asked a subcommittee of the National Research Council (NRC) to review, and develop when necessary, exposure guidance levels for 10 contaminants.

Overall, the subcommittee found the values proposed by the Navy to be suitable for protecting human health. For a few chemicals, the committee proposed levels that were lower than those proposed by the Navy. In conducting its evaluation, the subcommittee found that there is little exposure data available on the submarine environment and echoed a previous recommendation from an earlier NRC report to conduct monitoring that would provide a complete analysis of submarine air and data on exposure of personnel to contaminants.

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