Environment terminology · MLC-0121

Environment terms: R (1,657)

Page 1 of 4

R ValueA measure of insulation. The higher the R-value, the better walls and roofs will resist the transfer of heat...
Rabbit DiseasesIllnesses and conditions limited to the species Oryctolagus cuniculus
RaceThe data on race were derived from answers to the question on race that was asked of all people. The U.S...
RacehorseA horse trained to race other horses as sport
Racial GroupRace is a self-identification data item in which respondents choose the race or races with which they most...
Racial/Economic DisparityEconomic inequality as it relates to the race of an individual. This disparity may result in disproportionate...
Racing AnimalIncludes dogs, horses, pigs and other animals that are trained to race each other for human entertainment and...
Racing PigeonA specially bred and trained pigeon that participates in a sport where they are released from specific...
Racing VehicleA vehicle that has, in general, been extensively modified for racing, and is incapable of safe and practical...
Rack DryerAny equipment used to reduce the moisture content of grain in which the grain flows from the top to the...
Rack Reclamation UnitUnit that burns the coatings off racks used to hold small items for application of a coating. The unit burns...
Radar1. A system whereby short electromagnetic waves are transmitted and any energy which is scattered back by...
RadialBody parts on an invertebrate that are arranged in a circle around a single center.
Radial Body PartBody parts on an invertebrate that are arranged in a circle around a single center.
Radial CanalA part of the water vascular system of echinoderms. Specifically, a branch off of the ring canal that leads...
Radial NerveA major nerve of the upper extremity. In humans the fibers of the radial nerve originate in the lower...
Radial to ImpellerPerpendicular to the impeller shaft. Material being pumped flows at a right angle to the impeller.
Radiant Heat TransferRadiant heat transfer occurs when there is a large difference between the temperatures of two surfaces that...
Radiant TubeAny portion of the tube coil assembly located within the ethylene cracking furnace firebox whereby a thermal...
Radiation1. Radiation is energy emitted in the form of electromagnetic waves. Radiation has differing characteristics...
Radiation ContaminationRadioactive contamination occurs when radioactive material is deposited on or in an object or person. A...
Radiation EmergencyMay occur when radioactive material is released into the environment as the result of intentional actions or...
Radiation ExposureRadiation exposure, also called irradiation, occurs when radioactive material or a radiation machine emits...
Radiation InteractionRadiation Interaction involves the interaction of a stream of subatomic particles or transmitted energy waves...
Radiation ProtectionBasic radiation protection concepts can be applied separately or in combination to help limit people's...
Radiation sicknessA serious illness that can happen when a person is exposed to very high levels of radiation, usually over a...
Radiation StandardsRegulations that set maximum exposure limits for protection of the public from radioactive materials.
Radiation-Effect CoatingCoating or coating system engineered to interact, through absorption or reflection, with specific regions of...
Radiation-Induced Gene ExpressionRadiation-Induced Gene Expression involves activation or enhanced activity in the expression of a gene as a...
Radiation-Induced RecombinationAny recombination occuring in response to DNA breakage induced by ionizing radiation, and resolved with...
Radiative CoolingCooling process of the Earth's surface and adjacent air, which occurs when infrared (heat) energy radiates...
Radiative Forcing1. A measure of the influence of a particular factor (e.g. greenhouse gas (GHG), aerosol, or land use change)...
Radiative-Convective ModelThermodynamic models that determine the equilibrium temperature distribution for an atmospheric column and...
RadicalA group of atoms that is capable of remaining unchanged during a series of chemical reactions. Such...
Radical PolymerizationPolymerization using a free radical initiator
radicalsA radical molecule contains at least one unpaired electron. With few exceptions, these unpaired electrons...
Radio frequency1. The standard band of signal frequency (usually expressed in Herz/Hz) for transmitting broadcast signals in...
Radio Frequency Identification TrackingTracking Hazardous Waste Shipments across International Borders.
RadioactiveMaterial that undergoes a spontaneous emission of ionizing radiation from the nuclei of unstable nuclei to...
Radioactive AtomAn atom with an unstable nucleus that emits ionizing radiation (alpha particles, beta particles or gamma...
Radioactive Decay1. Spontaneous change in an atom by emission of charged particles and/or gamma rays.
Radioactive Disposal RegulationPart 191, subparts B and C of this chapter.
Radioactive equilibriumA state in which the formation of atoms by decay of a parent radioactive isotope is equal to its rate of...
Radioactive equilibrium ratioThe total concentration of radon decay products (RDPs) present divided by the concentration that would exist...
Radioactive FalloutRadioactive material in the air from a nuclear explosion that will cool into sand-like particles and fall to...
Radioactive Material1. Matter composed of or containing radionuclides subject to the Atomic Energy Act of 1954, as amended (42...
Radioactive MaterialsMaterials that emit ionizing radiation (alpha particles, beta particles and gamma rays).
Radioactive Mixed Waste1. A material that contains both hazardous waste subject to RCRA and source, special nuclear, or by-product...
Radioactive SubstancesSubstances that emit ionizing radiation.
Radioactive Waste1. Any waste that emits energy as rays, waves, or streams of energetic particles. Radioactive materials are...
Radioactive Waste DisposalPermanent isolation of spent nuclear fuel or radioactive waste from the accessible environment with no intent...
Radioactive Waste Disposal SystemAny combination of engineered and natural barriers that isolate spent nuclear fuel or radioactive waste after...
Radioactive Waste ManagementAny activity, operation, or process (except for transportation) conducted to prepare spent nuclear fuel or...
Radioactive Waste Storage1. Retention of spent nuclear fuel or radioactive wastes with the intent and capability to readily retrieve...
Radioactivity1. Energy emitted as particles or rays during the decay of an unstable isotope to a stable isotope.
Radiochemical AnalysisBranch of chemical analysis in which the amount and nature of radioactive materials present in a sample are...
RadiogenicRefers to health effects that are caused by exposure to ionizing radiation.
Radiogenic IsotopeCaused by ionizing radiation.
RadioisotopeRadioactive forms of the same element, with the same number of protons but different number of neutrons. For...
RadioisotopesChemical variants of radioactive elements with potentially oncogenic, teratogenic, and mutagenic effects on...
RadiologicalRelating to the science of radiology or nuclear radiation.
Radiological Agent Contamination EventHostile introduction into water, air, and soil of radioactive substances in a concentration that makes the...
Radiological DecontaminationRemoval of radioactive material from a structure, object or person.
Radiological Decontamination TechnologyTreatment process for rooms and furnishings in buildings, or the exterior environment that have been exposed...
Radiological Dispersion Device1. Any device that causes the purposeful dissemination of radioactive material through explosive methods or...
Radiological Emergency Response TeamHave been established by EPA's Office of Radiation Programs (ORP) to provide response and support for...
RadiologyA specialized field of medicine that makes use of ionizing radiation to generate images that visualize the...
RadioluminescenceThe emission of light from objects containing radioactive material, such as radium.
Radiometer1. A radiometer is an instrument for detecting and measuring the intensity of the sun's energy in the...
Radionuclide1. An unstable form of a chemical element that radioactively decays, resulting in the emission of nuclear...
Radionuclides1. Radioactive particle, man-made (anthropogenic) or natural, with a distinct atomic weight number. Can have...
RadiosondeBalloon-borne instrument that measures and transmits pressure. temperature. and humidity to a ground-based...
RadiumA naturally occurring radioactive (unstable) element that forms when uranium or thorium decay. Elevated...
Radius of Influence1. The radial distance from the center of a wellbore to the point where there is no lowering of the water...
Radius of Vulnerability ZoneThe maximum distance from the point of release of a hazardous substance in which the airborne concentration...
RadomeNon-metallic protective housing for electromagnetic transmitters and receivers (e.g., radar, electronic...
Radon1. A colorless naturally occurring, radioactive, inert gas formed by radioactive decay of radium atoms in...
Radon Action LevelHome owners should take action to lower radon levels indoors when levels are at or above 4 pCi/L.
Radon chamberAn airtight enclosure in which operators can induce and control different levels of radon gas and radon decay...
Radon Contractor Proficiency ProgramEPA's program to evaluate radon mitigation contractors and the contractor's ability to communicate...
Radon ControlMeasures taken to mitigate and eliminate the presence of radon gas in homes, offices and other buildings
Radon DaughtersShort-lived radioactive decay products of radon that decay into longer-lived lead isotopes that can attach...
Radon Decay Products1. A term used to refer collectively to the immediate products of the radon decay chain. These include...
Radon MapMap created to assist national, state and local organizations to target their resources and to implement...
Radon Measurement DeviceUnit, component, or system designed to measure radon gas or radon decay products.
Radon Measurement MethodMeans of measuring radon gas or radon decay products encompassing similar measurement devices, sampling...
Radon Measurement Proficiency Program ApplicantIndividual or organization that submits an application to the RMP program, including the individual...
Radon Mitigation ContractorContractor who provides radon mitigation services to the public.
Radula1. A flexible, toothed organ in the mouths of gastropods used to graze and scrape microscopic algae off hard...
RaffinateWhat is left behind after the more soluble portion of a material is removed. A liquid from which impurities...
RailIncludes "heavy" and "light" transit rail. Heavy transit rail is characterized by exclusive rights-of-way...
Rail CarNon-self-propelled vehicle designed for and used on railroad tracks.
Rail Tank CarCompletely enclosed storage vessel pulled by a locomotive that is used to transport liquid, solid, or gaseous...
Rail TransportationIndustries in the Rail Transportation subsector provide rail transportation of passengers and/or cargo using...
RailcarRailroad hopper car or boxcar.
Railcar Loading StationPortion of a metallic mineral processing plant where metallic minerals or metallic mineral concentrates are...
Railcar Unloading StationPortion of a metallic mineral processing plant where metallic ore is unloaded from a railcar into a hopper...
RailfieldAn extensive legacy of underutilized, contaminated, and sometimes abandoned rail properties also known as...
Railroad1. Commercial entity that operates locomotives to transport passengers or freight. [40 CFR 92.2 (CFR 2013)]
Railroad ClassificationDivision of railroad industry operating companies by the Interstate Commerce Commission into three...
Railroad Grade Crossing SurfaceMaterials placed between railroad tracks, and between the track and the road at highway and street railroad...
Railroad Heavy Maintenance FacilityFacilities engaged in the manufacture, overhaul, or heavy maintenance of railroad engines, cars, car-wheel...
Railroad Line Maintenance FacilityFacilities specified at § 438.1 that only perform routine cleaning and light maintenance on railroad engines...
Railroad Overhaul FacilityFacilities engaged in the manufacture, overhaul, or heavy maintenance of railroad engines, cars, car-wheel...
RainEither in the form of water drops larger than that of drizzle (0.02 inch / 0.5 mm), or smaller drops which...
Rain barrelMosquito-proof container used to collect and store rainwater that would otherwise wind up in storm drains and...
Rain ChainsA water feature that is used as an alternative to a downspout. Rain chains guide runoff from a roof to either...
Rain Erosion-Resistant CoatingCoating or coating system used to protect the leading edges of parts such as flaps, stabilizers, radomes...
Rain GageDevice-usually a cylindrical container-for measuring rain-fall.
Rain garden1. A garden that uses plants and layers of soil, sand and mulch to retain rainwater, reducing the amount of...
Rain gaugeAn instrument that measures the amount of rain that has fallen in a particular place.
Rainbow ReportComprehensive document giving the status of all pesticides now or ever in registration or special reviews...
RainfallThe amount of precipitation of any type, primarily liquid. It is usually the amount that is measured by a...
RainsplashThe displacement of sediment by bombardment of raindrops.
Rainwater FeatureUse rainwater and stormwater as their sole source and function as stormwater management elements. Examples...
Rainwater/Stormwater FeatureUse rainwater and stormwater as their sole source and function as stormwater management elements. Examples...
RainyThe Rainy River Basin and Lake of the Woods drainage within the United States. Minnesota. Area = 11400 sq.mi.
RaiseAn excavation of restricted cross-section, driven upwards either vertically or at an angle from a level in...
Raisin ProductionProduction of raisins from the following products: Dried grapes, all varieties, bleached and unbleached...
RakingA mechanical method of removing stumps, roots, and slash from a future planting site.
RalesAbnormal respiratory sound heard when listening for sounds within the body
Raman SpectroscopyEmission of electromagnetic energy with a shorter frequency (longer wavelength) than that of the incident...
Ramped-Modal Test Type1. Relating to a ramped-modal type of steady-state test, as described in the standard-setting part.
Ramping CapabilityAbility of a power station to change its output over time.
RANDOM ACCESS MEMORYComputer memory used to process and store data that can be accessed directly rather than sequentially.
Random Assignment1. The assignment of individuals in the pool of all potential participants to either the experimental...
Random Comparison Group DesignIn this research design, the comparison group is randomly selected from the population of interest, even...
Random error1. Variations of repeated measurements that are random in nature and not predictable individually. The causes...
Random Incident FieldSound field in which the angle of arrival of sound at a given point in space is random in time.
random sample1. Sample selected from a statistical population such that each sample has an equal probability of being...
Random samplesSamples selected from a statistical population such that each sample has an equal probability of being...
Random SamplingA procedure for sampling from a population that gives each unit in the population a known probability of...
Random Sampling Abatement System Testing ProgramRequired frequency for measuring the destruction or removal efficiencies of abatement systems in order to...
random variable1. A quantity which can take on any number of values but whose exact value cannot be known before a direct...
Randomization1. The process of imposing an element of chance on the selection of a sample. Randomization is a step in the...
Randomized Clinical TrialClinical trial in which persons are randomly assigned to exposure or treatment groups.
Randomized Comparative Change DesignIn the experimental design known as the randomized comparative change design a treatment and control group...
Randomized Comparative Post-test DesignIn the experimental design known as the randomized comparative post-test design a treatment and control group...
Range1. The spread from minimum to maximum values that an instrument is designed to measure.
Range Sensitivity AnalysisEvaluation of the model sensitivity across the entire range of values of the input variable(s).
Range (Species)Geographic area in which a plant or animal lives.
Range TopThe range burners or stove top and the oven are considered two separate appliances. Counted also with range...
Rangeland1. Land, mostly grasslands, whose plants can provide food (i.e., forage) for grazing or browsing animals. See...
RanitidineA non-imidazole blocker of those histamine receptors that mediate gastric secretion (H2 receptors). It is...
Rank CorrelationA “distribution free” or nonparametric statistic r that measures the strength and direction of association...
rank correlation coefficientA measure of the tendency for a Y value to increase, as its associated X value increases. It allows for...
Rank OrderingProcess or result of arranging a group of items in order according to their respective values of some...
RankineRankine is an absolute temperature scale often used in engineering. Using this scale, the freezing point of...
Ranney CollectorThis water collector is constructed as a dug well from 12 to 16 feet (3.5 to 5 m) in diameter that has been...
RanunculalesAn order of flowering plants
Ranunculus ficariaLesser celandine, also known as fig buttercup, is an herbaceous, perennial plant. Plants have a basal rosette...
Rapeseed OilOil obtained from the plants Brassica napus, Brassica rapa, or Brassica juncea. [40 CFR 80.401 (2023)]
Rapid ElasticityCapabilities can be elastically provisioned and released, in some cases automatically, to scale rapidly...
Rapid ExitPanels or rails that raise to release all cows on one side of the milking parlor at once.
Rapid Polymerase Chain Reaction TechnologyDetects and identifies in real time, pathogens and biowarfare agents, including anthrax, plague, and botulism...
Rapid Polymerase Chain Reaction ToolTool for rapid replication of DNA using the polymerase chain reaction.
Rapid Toxicity Testing SystemRapid toxicity technologiy intended to serve as quick screening tools for determining whether water being...
RapidsFast-flowing section of a stream, often shallow and with exposed rock or boulders.
Rapistrum rugosumAnnual bastard-cabbage is an annual, many-branched, herbaceous plant that grows from 1 to 5 feet or more in...
Raptor1. A bird of prey, including eagles, ospreys and hawks.
Rare Earth MetalsElements scandium, yttrium, and lanthanum to lutetium, inclusive.
RaspA machine that grinds waste into a manageable material and helps prevent odor.
Rat ModelRat as the biological model of human disease
Rate1. The per unit cost of insurance.
Rate of Progress1. For purposes of the 1-hour NAAQS, the progress reductions required under section 172(c)(2) and section...
Rate of SpreadRelative activity of a fire in extending its horizontal dimensions. It is expressed as a rate of increase of...
Rate Ratio1. Measure of association that quantifies the relation between an exposure and a health outcome from an...
Rate-based trading programA policy approach in which regulated sources can generate compliance instruments (i.e., credits or...
Rated CapacityMaximum sustainable capacity of the equipment.
Rated HorsepowerMaximum horsepower output of a locomotive engine in use.
Rated Module CurrentCurrent output of a photovoltaic module measured at standard test conditions of 1,000 w/m2 and 25°C cell...
Rated OutputMaximum power/thrust available for takeoff at standard day conditions as approved for the engine by FAA...
Rated Power1. Meaning given in § 1033.140.
Rated Pressure RatioRatio between the combustor inlet pressure and the engine inlet pressure achieved by an engine operating at...
Rated Speed1. Maximum full load governed speed for governed engines and the speed of maximum horsepower for ungoverned...
Rated-Speed EquipmentNonhandheld equipment in which the installed engine is intended for operation at a rated speed that is...
Ratepayer Impact Measure TestEvaluates impacts on customer rates by evaluating changes in utility revenues and operating costs.
RatholeHole in the rig floor, 30 to 35 feet deep, lined with casing that projects above the floor, into which the...
Ratio1. The relationship in quantity, amount, or size between two or more things.
Ratio MeasureA level of measurement which has all the attributes of nominal, ordinal, and interval measures, and is based...
Ratio ScaleMeasurement scale consisting of quantitative categories whose values are intervals with a true zero point...
RationFeed fed to an animal during a 24-hour period.
RationingMandatory water-use restrictions sometimes used under drought or other emergency conditions.
Ratoon Stunting DiseaseRatoon stunt is a major disease of sugarcane worldwide and in yield trials in South Florida the cane weight...
RattusOld World Rat.
RavelThe rolling or sloughing of sediment due to loss of cohesion in surface materials.
Raw Agricultural Commodity1. An unprocessed human food or animal feed crop (e.g., raw carrots, apples, corn, or eggs.)
Raw DataAny laboratory worksheets, records, memoranda, notes, or exact copies thereof, that are the result of...
Raw InkAll purchased ink.
Raw Material1. Basic input materials to a renderer composed of animal and poultry trimmings, bones, meat scraps, dead...
Raw Material EquivalentEqual to the raw material usage multiplied by the volume of air scrubbed via wet scrubbers divided by the...
Raw Material FeedPrepared and mixed materials, which include but are not limited to materials such as limestone, clay, shale...
Raw Material MineralMinerals, such as silica sand, limestone, and dolomite; inorganic chemical compounds, such as soda ash...
Raw Materials Preparation Section1. Equipment located at a polymer manufacturing plant designed to prepare raw materials, such as monomers and...
Raw MillBall and tube mill, vertical roller mill or other size reduction equipment, that is not part of an in-line...
Raw Mill DryerBall and tube mill, vertical roller mill or other size reduction equipment, that is not part of an in-line...
Raw SeafoodRaw material, including freshwater and saltwater fish and shellfish, to be processed, in the form in which it...
Raw Sewage1. Untreated municipal sewage.
Raw Sewage ReleaseRelease of untreated domestic or commercial waste water.
Raw Starch HydrolysisProcess of hydrolyzing corn starch into simple sugars at low temperatures, generally not exceeding 100 °F (38...
Raw Water1. Water in its natural state, prior to any treatment for drinking.
Rayleigh WaveA Rayleigh wave is a seismic surface wave causing the ground to shake in an elliptical motion, with no...
Rayon FiberManufactured fiber composed of regenerated cellulose, as well as manufactured fibers composed of regenerated...
RBOB-Summer (Reformulated Blendstock for Oxygenate Blending)Petroleum product which, when blended with a specified type and percentage of oxygenate, meets the definition...
RBOB-Winter (Reformulated Blendstock for Oxygenate Blending)Petroleum product which, when blended with a specified type and percentage of oxygenate, meets the definition...
RCRA 3008 OrderOrder 3008(h) authorizes EPA to issue administrative (i.e., enforcement) orders or bring court action to...
RCRA Approved Test MethodIncludes Test Method 9095 (Paint Filter Liquids Test) in “Test Methods for Evaluating Solid Waste...
RCRA Cleanup Baseline1. EPA developed the RCRA Cleanup Baseline in conjunction with the states as a result of a mandate in the...
RCRA ClusterRCRA Clusters cover a period of one year and apply to both HSWA and Non-HSWA final rules published from July...
RCRA Corrective ActionEPA can require treatment, storage and disposal (TSDF) facilities handling hazardous waste to undertake...
RCRA Facility Assessment1. A RFA is performed at a facility to determine the existence of any continuous or non-continuous releases...
RCRA Facility Investigation1. The purpose of a RFI is to gather sufficient data at a facility to fully characterize the nature, extent...
RCRA Hazardous Waste1. A national regulatory designation for certain wastes under the Resource Conservation and Recovery Act...
RCRA Institutional ControlNon-engineering controls used to restrict land use or land access in order to protect people and the...
RCRA Regulated UnitsSurface impoundments, waste piles, land treatment units, and landfills that received hazardous waste after...
RCRA Standardized PermitSpecial form of RCRA permit, that may consist of two parts: A uniform portion that the Director issues in all...
RCRA Statutory ChecklistThe RCRA Statutory Checklist is the current document used by a state to document its authority for the...
RCRAInfoA database that tracks RCRA Subtitle C facility-specific data (i.e., events and activities related to...
Reach1. Stream segment.
Reach CodeA unique 14-digit identification code assigned to a National Hydrography Dataset reach, which is a continuous...
Reach fileA series of national hydrologic databases that uniquely identify and interconnect the stream segments or...
Reactant1. Chemical substance that is used intentionally in the manufacture of a polymer to become chemically a part...
Reaction CenterA protein complex that uses light energy to create a stable charge separation by transferring a single...
Reaction ProductSubstance that is made in the chemical reaction.
Reaction RateThe rate at which a reaction takes place.
Reaction Rate CoefficientA constant describing the rate of transformation of a substance in an environmental medium characterized by a...
Reaction Spinning ProcessFiber-forming process where a prepolymer is extruded into a fluid medium and solidification takes place by...
Reaction WoodWood with distinctive anatomical and physical characteristics, formed typically in parts of leaning or...
reactive1. Having the tendency to chemically combine with something else and change its form. For example, a strong...
Reactive Dye[A dye in the class of] dyes that bond to fiber molecules and are fixed by reacting chemically, especially...
Reactive FluxingUse of any gas, liquid, or solid flux (other than cover flux) that results in a HAP emission. Argon and...
Reactive Functional GroupAtom or associated group of atoms in a chemical substance that is intended or can reasonably be anticipated...
Reactive Gaseous MercuryThe major removal mechanism (of mercury in the atmosphere) is by oxidation of Hg(0) to divalent mercury...
Reactive MaterialEnergetics, organic peroxides, and unstable chemicals such as chemicals that react violently with water and...
reactive nitrogen1. All biologically, chemically, and radiatively active nitrogen compounds in the atmosphere and biosphere...
Reactive Nitrogen EmissionEmission of all biologically, chemically, and radiatively active nitrogen compounds in the atmosphere and...
Reactive Oxygen IntermediateSuperoxide anion.
Reactive Oxygen SpeciesMolecules or ions formed by the incomplete one-electron reduction of oxygen. These reactive oxygen...
Reactive Power1. The portion of electricity that establishes and sustains the electric and magnetic fields of...
Reactive SolidAny extremely hazardous substance denoted with “a” in the “Notes” column in Appendix A or B of this part.
Reactivity1. Refers to those hazardous wastes that are normally unstable and readily undergo violent chemical change...
Reactivity Characteristic1. The characteristic which identifies wastes that readily explode or undergo violent reactions.
Reactivity FactorMeasure of the change in mass of ozone formed by adding a gram of a VOC to the ambient atmosphere, expressed...
Reactor1. Any vessel in which vinyl chloride is partially or totally polymerized into polyvinyl chloride.
Reactor Batch Process VentBatch process vent originating from a reactor.
Reactor LiquidCompound or material made in the reactor, even though the substance may be transferred to another vessel...
Reactor Opening LossEmissions of vinyl chloride occurring when a reactor is vented to the atmosphere for any purpose other than...
Reactor ProcessUnit operations in which one or more chemicals, or reactants other than air, are combined or decomposed in...
Reactor Process VentBatch or continuous process vent originating from a reactor. 40
Reactor Site ProcessOnce the fuel assemblies are fabricated, trucks transport them to the reactor sites. The fuel assemblies are...
Read Across from Analogs/Categories"Read across" is a technique of filling data gaps. To "read across" is to apply data from a tested chemical...
READ ONLY MEMORYComputer memory whose contents cannot be changed by the user.
READERA device that enlarges microimages for viewing.
READER-PRINTERA device used to enlarge microimages for viewing and to produce a hard copy of the enlarged image. See also...
Readiness Review1. A systematic, documented review of the readiness for the start-up or continued use of a facility, process...
READING FILESOutgoing correspondence records arranged chronologically, in contrast to those arranged by subject. Sometimes...
Ready for Anticipated Use - No1. The event by which the State or EPA makes an RAU determination and completes an RAU form. The form notes...
Ready for Anticipated Use - Yes1. The event by which the State or EPA makes an RAU determination and completes an RAU form. The form notes...
Ready for ReuseA property is considered ready for reuse when it has either been investigated and requires no further action...
Ready-Mix Concrete ManufacturingMaking concrete mixtures that are delivered to the user in an unhardened state
Ready-to-feedInfant and baby products (formula, juices, beverages, baby food), and table foods that do not need to have...
Reaeration1. The net flux of oxygen occurring from the atmosphere to a body of water with a free surface.
Reagent1. (re-A-gent) A pure chemical substance that is used to make new products or is used in chemical tests to...
Reagent Blank1. A sample consisting of reagent(s), without the target analyte or sample matrix, introduced into the...
Reagent Water1. Water demonstrated to be free from the analytes of interest and potentially interfering substances at the...
Real DollarForecast dollars that are adjusted for inflation.
Real DollarsForecast dollars that are adjusted for inflation.
Real Estate IndustryIndustries in the Real Estate subsector group establishments that are primarily engaged in renting or leasing...
Real PowerThe portion of electricity that supplies energy to the load.
Real Property1. Land, including land improvements, structures and appurtenances thereto, excluding movable machinery and...
Real Property AcquisitionIncludes all activities necessary in the acquisition of real property related to a regional Response Action...
Real World CommunitySometimes used to identify those communities whose existence does not depend on the availability of mass...
Real-Time DataData collected by automated instrumentation and telemetered and analyzed quickly enough to influence a...
Real-Time Electricity PricingReal-time pricing (RTP) is generally an hourly rate which is applied to usage on an hourly basis.
Real-Time Feed MonitoringSystem designed to track the rate of feed consumption and to detect uneaten feed passing through the nets at...
Real-time hand recordingMethod by which trained observers manually record information on children's behavior.
Real-time MeasurementMethods that use real-time instruments are used to sample and measure the parameter continuously, such as...
Real-Time MonitoringMonitoring and measuring environmental developments with technology and communications systems that provide...
ReamFive hundred sheets of paper.
Rearing HabitatAn area where larval and juvenile fish find food and shelter.
Reason RestrictedReason why the document is not shown on Regulations.gov; it might include confidential business information...
Reasonable AlternativeReasonable range of alternatives that are technically and economically feasible, and meet the purpose and...
Reasonable CompensationWith respect to a regularly employed officer or employee of any person, compensation that is consistent with...
Reasonable CostCost that, in its nature or amount, does not exceed that which would be incurred by a prudent person under...
Reasonable Explanation1. The final consideration in a strength-of-evidence analysis. If the results of a strength-of-evidence...
Reasonable Further Progress1. Annual incremental reductions in air pollutant emissions as reflected in a State Implementation Plan that...
Reasonable Further Progress BaselineTotal of actual volatile organic compounds or nitrogen oxides emissions from all anthropogenic sources in an...
Reasonable Further Progress PlanAny incremental emissions reductions required by the CAA (e.g., section 182(b)) and approved by the EPA as...
Reasonable maximum exposure1. The maximum exposure reasonably expected to occur in a population.
Reasonable Maximum Exposure RiskThe estimated risk corresponding to the reasonable maximum exposure.
Reasonable PaymentWith respect to professional and other technical services, a payment in an amount that is consistent with the...
Reasonable Record-Access AssistanceProviding timely and unobstructed access to test products or products and records required by this part and...
Reasonable Technical BasisInformation that would lead a person familiar with engine design and function to reasonably believe a...
Reasonable Worst Case1. An estimate of the individual dose, exposure, or risk level received by an individual in a defined...
Reasonableness CheckInvolve items like order-of-magnitude, unit, and other checks to ensure that the numbers are in the range of...
Reasonably Anticipated CharacteristicThat a knowledgeable person would expect a given physical or chemical composition or characteristic to occur...
Reasonably Attributable ConditionAttributable by visual observation or any other appropriate technique.
Reasonably Attributable ImpactAttributable by visual observation or any other technique the State deems appropriate.
Reasonably Attributable Visibility ImpairmentVisibility impairment that is caused by the emission of air pollutants from one, or a small number of sources.
Reasonably Available Control MeasuresA broadly defined term referring to technological and other measures for pollution control.
Reasonably Available Control Technology1. Control technology that is reasonably available, and both technologically and economically feasible...
Reasonably Available InformationInformation that EPA possesses or can reasonably generate, obtain and synthesize for use, considering the...
Reasonably Foreseeable EmissionProjected future direct and indirect emissions that are identified at the time the conformity determination...
Reasonably Foreseeable EmissionsProjected future direct and indirect emissions that are identified at the time the conformity determination...
Reasonably Likely ExposureExposure to a chemical substance which, under foreseeable conditions of manufacture (including import)...
Rebond FoamFoam resulting from a process of adhering small particles of foam (usually scrap or recycled foam) together...
Rebond Foam ProcessEquipment used to produce a rebond foam product. For the purpose of this subpart, the rebond foam process...
rebound1. The uplift of land following deglaciation due to the mass of ice being removed from the land surface.
Rebound effectThe reduction in expected gains from improvements in the energy efficiency of a technology that results from...
RebrickingCold replacement of damaged or worn refractory parts of the glass melting furnace. Rebricking includes...
Rebuilt Vehicular PartVehicular parts that have been remanufactured, reusing parts in their original form.
ReburningReducing the coal and combustion air to the main burners and injecting a reburn fuel (such as gas or oil) to...
Rebuttable PresumptionFor purposes of RCRA, an objective test that focuses on the halogen level in used oil to determine whether...
recalcitrantUnreactive, nondegradable; refractory.
Recapture Device1. Individual unit of equipment capable of and used for the purpose of recovering chemicals, but not normally...
Recarbonation(re-CAR-bun-NAY-shun) A process in which carbon dioxide is bubbled into the water being treated to lower the...
RecarbonizationProcess in which carbon dioxide is bubbled into water being treated to lower the pH.
Received DateDate that the document was created in FDMS.For a comment submitted through Regulations.gov, this marks the...
Receiver1. A device which indicates the result of a measurement. Most receivers in the water utility field use either...
Receiving FacilityU.S. facility which, under RCRA and other applicable domestic laws, is operating or is authorized to operate...
Receiving PropertyAny residential or commercial property that receives the sound from railroad facility operations, but that is...
Receiving Property Measurement LocationLocation on receiving property that is on or beyond the railroad facility boundary and that meets the...
Receiving Water1. The "Water of the United States" as defined in 40 CFR 122.2 into which the regulated stormwater discharges.
Receiving Water Load Allocation1. Portion of a receiving water's loading capacity that is attributed either to one of its existing or future...
Receiving Waters1. Lakes, rivers, wetlands, coastal waters, and groundwaters that receive runoff.
Receptor1. The ecological entity exposed to the stressor.
Receptor AgeThe description of the exposed individual as defined by the EPA region or dictated by the site.
Receptor BindingReceptor Binding involves a temporary non-covalent, typically highly specific and high affinity, interaction...
Receptor (Ecology)1. The ecological entity exposed to the stressor. [EPA 1998, EPA 2005b][Thesaurus of Terms Used in Microbial...
Receptor Mediated EndocytosisA process by which cells internalize molecules or viruses. Receptors on the plasma membrane of the target...
Receptor ModelA receptor model determines the statistical contribution of various sources to pollutant concentrations at a...
Receptor Population1. The exposed individual relative to the exposure pathway considered.
Re-CertificationAny action taken by the Administrator pursuant to section 8(f) of the WIPP LWA.
Recessional MoraineAn end or lateral moraine, built during a temporary - but significant - halt in the final retreat of a...
Recessive AlleleAn allele whose properties are not observed because they are masked by the expression of a dominant allele...
Recharge1. The process by which precipitation seeps into the groundwater system.
Recharge Area1. An area of land where there is a net annual transfer of water from the surface to ground water; where...
Recharge AreasAreas where infiltration to aquifers occurs.
Recharge Rate1. The quantity of water per unit time that replenishes or refills an aquifer.
Recharge ZoneArea through which water enters the Edwards Underground Reservoir as defined in the December 16, 1975, Notice...
Rechargeable BatteryA battery that can be charged, discharged, and recharged, and the cycle can be repeated
Rechargeable Energy Storage SystemComponent(s) of a hybrid engine or vehicle that store recovered energy for later use, such as the battery...
Recipe1. Specific composition, from among the range of possible compositions that may occur within a product, as...
RECIPIENT1. An organization receiving financial assistance directly from Federal awarding agencies to carry out a...
Recipient PlantLiving plant in which the plant-incorporated protectant is intended to be produced and used.
Reciprocating Compressor1. Piece of equipment that increases the pressure of a process gas by positive displacement, employing linear...
Reciprocating Compressor Rod PackingSeries of flexible rings in machined metal cups that fit around the reciprocating compressor piston rod to...
Reciprocating DeviceUses the flow of water to produce the lift or drag of an oscillating part transverse to the flow direction...
Reciprocating Internal Combustion EngineEngines which use pistons that alternatively move back and forth to convert pressure into rotating motion...
Reciprocating Rotary EngineEngine with pistons that convert pressure into rotational motion.
Recirculated AirAir removed from the conditioned space and used for ventilation, heating, cooling, humidification, or...
Recirculated Cooling WaterWater which is passed through the main condensers for the purpose of removing waste heat, passed through a...
Recirculating Media Filter1. Wastewater treatment system component featuring a layer of sand, gravel, or other material, on which...
Recirculating SystemSystem that filters and reuses water in which the aquatic animals are produced prior to discharge...
RecirculationCold rolling operations which include recirculation of rolling solutions at all mill stands.
Recirculation EquipmentPart of the catalytic reforming unit that reforms or changes the chemical structure of naphtha.
recirculation systemA type of in-situ bioremediation system designed to increase the hydraulic gradient and accelerate the...
Recirculation TankTank used in a scrubbing system to (1) provide sufficient time for reagents to dissolve into the liquid, and...
Reclaim1. To reprocess refrigerant to at least the purity specified in the Air-Conditioning, Heating, and...
Reclaim Refrigerant1. To reprocess refrigerant to all of the specifications in appendix A to 40 CFR part 82, subpart F (based on...
ReclaimedFor purposes of defining a material as a solid waste under RCRA Subtitle C, a material is reclaimed if it is...
Reclaimed MaterialIs “reclaimed” if it is processed to recover a usable product, or if it is regenerated. Examples are recovery...
Reclaimed materialsWaste materials and byproducts that have been recovered or diverted from the waste stream for reuse.
Reclaimed Water1. Treated wastewater that can be used for beneficial purposes, such as irrigating certain plants.
ReclaimerMachine used to remove perchloroethylene from articles by tumbling them in a heated air stream (see dryer).
Reclamation1. Restoration of mined land to original contour, use, or condition. Also describes the return of land to...
Reclamation AreaSurface area of a coal mine which has been returned to required contour and on which revegetation...
Reclamation PlanPlan detailing activities and milestones to accomplish reclamation of impoundments or piles containing...
Reclamation Site1. Drastically disturbed land that is reclaimed using sewage sludge. This includes, but is not limited to...
Recognized ExpertA recognized expert can be a university professor or member of a professional society in a discipline such as...
Recognized Test KitCommercially available kit recognized by EPA under § 745.88 as being capable of allowing a user to determine...
Recombinant Bacteria1. A microorganism whose genetic makeup has been altered by deliberate introduction of new genetic elements...
Recombinant DNA1. The new DNA that is formed by combining pieces of DNA from different organisms or cells.
Recombinant DNA TechnologyProcedure used to join together DNA segments in a cell-free system (an environment outside a cell or...
RecombinasesA broad category of enzymes that are involved in the process of genetic recombination.
RecombinationAction of a free electron falling back into a hole. Recombination processes are either radiative, where the...
Recombination RepairHomologous recombination can operate at both double-strand breaks and free ends. The homologous chromosome...
Recommencing DischargerSource which recommences discharge after terminating operations.
Recommended DecisionRecommended findings and conclusions of the Presiding Officer in an expedited hearing.
Recommended Exposure LimitRELs are occupational exposure limits for chemical and physical agents established by the National Institute...
Recommended Exposure Limits1. Recommendations made by the National Institute for Occupational Safety and Health (NIOSH).
Recommended Maximum Contaminant LevelThe maximum level of a contaminant in drinking water at which no known or anticipated adverse effect on human...
Recommended PracticeMeaning given in § 1065.201
Reconciliation PeriodThe period of time during which a seller generates water quality credits and a buyer purchases and uses those...
Re-CondenserHeat exchangers that cool compressed boil-off gas to a temperature that will condense natural gas to a liquid.
Reconfigured Emission-Data VehicleEmission-data vehicle obtained by modifying a previously used emission-data vehicle to represent another...
Reconstituted Wood Product Board CoolerPiece of equipment designed to reduce the temperature of a board by means of forced air or convection within...
Reconstituted Wood Product PressPress, including (if applicable) the press unloader, that presses a resinated mat of wood fibers, particles...
Reconstructed Existing Control DeviceFor the purposes of these standards, the capital expenditure of at least 50 percent of the replacement cost...
Reconstructed FacilityExisting facility which upon reconstruction becomes an affected facility, irrespective of any change in...
Reconstructed Potroom GroupExisting potroom group for which the components are replaced to such an extent that the fixed capital cost of...
Reconstructed Source1. Facility in which components are replaced to such an extent that the fixed capital cost of the new...
Reconstruction1. Will be presumed to have taken place where the fixed capital cost of the new component exceeds 50 percent...
Reconstruction of DoseEstimating exposure after it has occurred by using evidence within an organism such as chemical levels in...
Record1. A completed document that provides objective evidence of an item or process. Records may include...
RECORD COMPONENTSIn records disposition, those elements of audiovisual, microform, and certain other special records, needed...
Record FloodingFlooding which equals or exceeds the highest stage or discharge at a given site during the period of record...
RECORD GROUPA body of organizationally related records established by an archival agency after considering the...
RECORD LAYOUTIn electronic records, a diagram or list of the contents of a logical record describing each data field's...
Record of Decision1. A public document that explains which cleanup alternative was selected for a Superfund site.
Record of Decision AmendmentSignificant change from the original selected remedy stated in the original Record of Decision (ROD), such as...
Record RetentionRecord Retention involves the operations surrounding the management of the official documents and records for...
Record ReviewRecord reviews are defined as a review of records, conducted at the government agency’s offices, for the...
RECORD SERIESA records series consists of documents or file units arranged according to a filing system or kept together...
Recordation Record1. With regard to allowances, the transfer of allowances by the Administrator from one Allowance Tracking...
RECORDED INFORMATIONInformation placed on a medium, such as paper, computer disk, or microform, to be available for later...
RecorderA device that creates a permanent record, on a paper chart or magnetic tape, of the changes of some measured...
RECORDING DENSITYIn electronic records, the number of bits in a single linear track per unit of length of a recording medium...
Recordkeeping1. The act or process of creating and maintaining records. Assumes the need for their proper disposition.
RECORDKEEPING COPYThe copy of a record that is captured and maintained in a recordkeeping system.
RECORDKEEPING REQUIREMENTSStatements in statutes, regulations, or agency directives providing general and specific guidance on...
RECORDKEEPING SYSTEMA manual or automated system in which records are collected, organized, and categorized to facilitate their...
records1. Includes all books, papers, maps, photographs, machine-readable materials, or other documentary materials...
RECORDS ADMINISTRATION INFORMATION CENTERAn information clearinghouse operated by NARA for Federal records managers and others.
Records AdministratorsRecords administrators maintain file plans and records in ECMS for an organization.
RECORDS CENTERA facility for the low-cost storage and servicing of records pending their disposal or transfer to the...
RECORDS CREATIONThe first stage of the records life cycle in which records are made (or received) by an office.
RECORDS CREATION AND MAINTENANCE PROGRAMPolicies and practices designed to ensure the creation and preservation of complete and accurate records...
RECORDS LIAISON OFFICERA person responsible for overseeing a records management program in a headquarters or field office in...
RECORDS MAINTENANCE AND USEAny action involving the storage, retrieval, and handling of records kept in offices by, or for, a Federal...
Records Management1. Activities related to the policies, procedures and tracking of records of Agency business from creation to...
RECORDS MANAGEMENT OFFICERThe person assigned responsibility by the agency head for overseeing an agency wide records management...
RECORDS MANAGEMENT PROGRAMA planned, coordinated set of policies, procedures, and activities needed to manage an agency's recorded...
RECORDS SCHEDULEAlso called records disposition schedule, records control schedule, records retention schedule, records...
RecoverTo remove refrigerant in any condition from an appliance and store it in an external container without...
Recover Refrigerant1. Remove refrigerant in any condition from an appliance and to store it in an external container without...
Recoverable CoalThe coal that is or can be extracted from a coal bed during mining.
Recoverable ResourceMaterials that still have useful physical, chemical, or biological properties after serving their original...
Recovered Fiber1. Postconsumer fiber such as: Paper, paperboard, and fibrous materials from retail stores, office buildings...
Recovered GasGas recovered through the separation process during flowback. [40 CFR 60.5430b (CFR 2024)]
Recovered Gaseous ButaneButane recovered from petroleum storage tanks as the gas which bubbles out of the liquid is recovered instead...
Recovered LiquidCrude oil, condensate or produced water recovered through the separation process during flowback. [40 CFR...
Recovered Material1. Waste materials and byproducts which have been recovered or diverted from solid waste, but such term does...
Recovered MaterialsWaste materials and byproducts that have been recovered or diverted from solid waste, but does not include...
Recovered Materials Advisory NoticeA notice that provides suggested recycled content levels and other purchasing information for each item...
Recovered Materials Advisory NoticesRecovered Materials Advisory Notices (RMANs) provide purchasing guidance and recommend recovered and...
Recovered Materials Content LevelsThe minimum amount of recovered material that designated items under the federal procurement program should...
Recovered Organic Material FertilizerSingle or blended substance, made from organic matter such as plant and animal by-products, manure-based or...
Recovered Paper1. Postconsumer fiber such as: Paper, paperboard, and fibrous materials from retail stores, office buildings...
Recovered SolventSolvent captured from liquid and gaseous process streams that is concentrated in a control device and that...
Recovering EcosystemAn ecosystem that is returning to its pre-disturbance condition
Recovery1. Refers to the diversion of materials from the municipal solid waste stream for the purpose of recycling or...
Recovery Device1. Individual unit of equipment capable of and normally used for the purpose of recovering chemicals for: (i)...
Recovery Efficiency1. The percentage of refrigerant in an appliance that is recovered by a piece of recycling or recovery...
Recovery EquipmentGeneral term used for devices that are used to recover and provide for reuse, chemical substances that...
Recovery Furnace1. Either a straight kraft recovery furnace or a cross recovery furnace, and includes the direct-contact...
Recovery Operation1. Collection of off-site material management units, process vents, and equipment components used at a plant...
Recovery Operations Equipment1. Equipment used to separate the components of process streams. Recovery operations equipment includes...
Recovery ProcessRegeneration and/or recovery of materials used, but not consumed, in manufacturing operations.
Recovery RatePercentage of usable recycled materials that have been removed from the total amount of municipal solid waste...
Recovery System1. Individual unit or series of material recovery units, such as absorbers, condensers, and carbon adsorbers...
Recreational ApplicationApplication in which a vehicle is ridden primarily for pleasure. Note that engines used in reduced-scale...
Recreational EquipmentDevices that people use for enjoyment or self-fulfillment activities, generally in their spare time.
Recreational Fishing1. Harvesting fish for fun and personal use, never for sale.
Recreational HuntingHarvesting wildlife and game for challenge and personal use, never for sale.
Recreational Land UseUse of lands for leisure activities, such as hiking or camping.
Recreational Marine Engine1. Category 1 propulsion marine engine that is intended by the manufacturer to be installed on a recreational...
Recreational RunningRunning for fun and health.
Recreational Vehicle1. Vehicles that are subject to evaporative emission standards in 40 CFR part 1051. This generally includes...
Recreational Vessel1. Meaning given in 46 U.S.C. 2101 (25), but excludes “passenger vessels” and “small passenger vessels” as...
Recreational/sport fishermenIndividuals who catch fish as part of a sporting or recreational activity and not for the purpose of...
Recruitment1. The addition of new individuals to a population by reproduction, commonly measured as the proportion of...
Rectangular HyperbolaA mathematical function of the form "y squared equals x squared plus c squared", where x and y are variables...
RectumThe distal segment of the large intestine, between the sigmoid colonand the anal canal.
RecumbentLying down
Recurrent Expenditure1. Expenses associated with the activities of a continuing environmental program. All expenditures are...
RECURRENT EXPENDITURESThose expenses associated with the activities of a Continuing Environmental Program. All expenditures, except...
RecyclableProducts or materials that can be collected, separated, and processed to be used as raw materials in the...
Recyclables1. Refers to those materials recovered from the solid waste stream and transported to a processor or end user...
Recycle1. Minimizing waste generation by recovering and reprocessing usable products that might otherwise become...
Recycle Refrigerant1. To extract refrigerant from an appliance and clean refrigerant for reuse without meeting all of the...
Recycle Water TreatmentSubpart J, § 440.104 includes, but is not limited to pH adjustment, settling and pH adjustment, settling, and...
RecycledFor purposes of defining a material as a solid waste under RCRA Subtitle C, a material is recycled if it is...
Recycled CoatingArchitectural coating that contains some portion of post-consumer coating. Recycled architectural coatings...
Recycled ContentThe portion of a product's or package's weight that is composed of materials that have been recovered from...
Recycled Input CreditWARM calculates the recycled input credit by assuming that the recycled material avoids - or offsets - the...
Recycled MaterialA material that is used in place of a primary, raw or virgin material in manufacturing a product.
Recycled Onsite Hazardous Air Pollutant SolventReuse of an organic HAP solvent in a process other than cleaning or washoff.
Recycled PaperEPA does not defined this term. According to the Federal Trade Commission's (FTC) Guides for Environmental...
Recycled Polychlorinated BiphenylsThose PCBs which appear in the processing of paper products or asphalt roofing materials from...
Recycled WaterWater that is used more than one time before it passes back into the natural hydrologic system.
Recycled-content materialsMaterials that contain pre- or post-consumer recycled content. Purchasing recycled products creates markets...
Recycle/ReuseRecycle/reuse of wastewater or a portion of the wastewater stream.
Recycling1. The separation and collection of wastes, their subsequent transformation or remanufacture into usable or...
Recycling and Reuse Business Assistance CentersLocated in state solid-waste or economic-development agencies, these centers provide recycling businesses...
Recycling Economic Development AdvocatesIndividuals hired by state or tribal economic development offices to focus financial, marketing, and...
Recycling MillFacility where recovered materials are remanufactured into new products.
Recycling PlantRefers to a facility where recovered materials are remanufactured into new products.
Recycling PresumptionThe assumption that all used oil that is generated will be recycled.
Recycling RateRecycling rate = Total recycled (by weight) divided by total discarded (by weight) + recycled (by weight)
Recycling Technical Assistance Partnership National NetworkA national information-sharing resource designed to help businesses and manufacturers increase their use of...
RedThe Red River Basin within the United States including the Devils Lake closed basin. Minnesota, North Dakota...
Red AlgaePlants of the division Rhodophyta, commonly known as red algae, in which the red pigment (phycoerythrin)...
Red BorderAn EPA document undergoing review before being submitted for final management decision-making.
Red, Green, and BlueThe primary additive colors used in display devices and scanners. Commonly used to refer to the color space...
Red HeadwatersThe North Fork Red River, Prairie Dog Town Fork Red River, and the Salt Fork Red River Basins. New Mexico...
Red Tide1. A dense outburst of dinoflagellates that colors the water reddish-brown. Certain dinoflagellates can...
Red-Band DiseaseA disease of corals manifested by a narrow band of filamentous cyanobacteria that advances slowly across the...
ReddNest made in gravel, consisting of a depression hydraulically dug by a fish for egg deposition (and then...
Redemption Program1. Refers to a program where consumers are monetarily compensated for the collection of recyclable materials...

1,657 of 30,736 terms in Environment terminology (MLC-0121). Request the full dataset.