Laboratory Terms D

A glossary of science, chemistry, environmental and laboratory terms.

Analytical testing dots



A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |



117 results match your search term:  D


Data Call-In
A part of the Office of Pesticide Programs (OPP) process of developing key re...

Find the meaning of the term: Data Call-In...


Data Quality Objectives DQOs
Qualitative and quantitative statements of the overall level of uncertainty t...

Find the meaning of the term: Data Quality Objectives DQOs...


Day Tank
Another name for deaerating tank.

Find the meaning of the term: Day Tank...


DDT
The first chlorinated hydrocarbon insecticide chemical name

Find the meaning of the term: DDT...


Dead End
The end of a water main which is not connected to other parts of the distribu...

Find the meaning of the term: Dead End...


Deadmen
Anchors drilled or cemented into the ground to provide additional reactive ma...

Find the meaning of the term: Deadmen...


Decant
To draw off the upper layer of liquid after the heaviest material (a solid or...

Find the meaning of the term: Decant...


Decay Products
Degraded radioactive materials, often referred to as "daughters" or "progeny"...

Find the meaning of the term: Decay Products...


Dechlorination
Removal of chlorine from a substance.

Find the meaning of the term: Dechlorination...


Decomposition
The breakdown of matter by bacteria and fungi, changing the chemical makeup a...

Find the meaning of the term: Decomposition...


Decontamination
Removal of harmful substances such as noxious chemicals, harmful bacteria or ...

Find the meaning of the term: Decontamination...


Deep-Well Injection
Deposition of raw or treated, filtered hazardous waste by pumping it into dee...

Find the meaning of the term: Deep-Well Injection...


Deflocculating Agent
A material added to a suspension to prevent settling.

Find the meaning of the term: Deflocculating Agent...


Defluoridation
The removal of excess flouride in drinking water to prevent the staining of t...

Find the meaning of the term: Defluoridation...


Defoliant
An herbicide that removes leaves from trees and growing plants.

Find the meaning of the term: Defoliant...


Degasification
A water treatment that removes dissolved gases from the water.

Find the meaning of the term: Degasification...


Degree-Day
A rough measure used to estimate the amount of heating required in a given ar...

Find the meaning of the term: Degree-Day...


Delegated State
A state (or other governmental entity such as a tribal government) that has r...

Find the meaning of the term: Delegated State...


Delist
Use of the petition process to have a facility's toxic designation rescinded.

Find the meaning of the term: Delist...


Demand-side Waste Management
Prices whereby consumers use purchasing decisions to communicate to product m...

Find the meaning of the term: Demand-side Waste Management...


Demineralization
A treatment process that removes dissolved minerals from water.

Find the meaning of the term: Demineralization...


Denitrification
The biological reduction of nitrate to nitrogen gas by denitrifying bacteria ...

Find the meaning of the term: Denitrification...


Dense Non-Aqueous Phase Liquid DNAPL
Non-aqueous phase liquids such as chlorinated hydrocarbon solvents or petrole...

Find the meaning of the term: Dense Non-Aqueous Phase Liquid DNAPL...


Density
A measure of how heavy a specific volume of a solid, liquid, or gas is in com...

Find the meaning of the term: Density...


Depletion Curve
In hydraulics, a graphical representation of water depletion from storage-str...

Find the meaning of the term: Depletion Curve...


Depressurization
A condition that occurs when the air pressure inside a structure is lower tha...

Find the meaning of the term: Depressurization...


Dermal Absorption
Process by which a chemical penetrates the skin and enters the body as an int...

Find the meaning of the term: Dermal Absorption...


Dermal Exposure
Contact between a chemical and the skin.

Find the meaning of the term: Dermal Exposure...


Dermal Toxicity
The ability of a pesticide or toxic chemical to poison people or animals by c...

Find the meaning of the term: Dermal Toxicity...


DES
A synthetic estrogen, diethylstilbestrol is used as a growth stimulant in foo...

Find the meaning of the term: DES...


Desalination
[Desalinization] (1) Removing salts from ocean or brackish water by using var...

Find the meaning of the term: Desalination...


Desiccant
A chemical agent that absorbs moisture; some desiccants are capable of drying...

Find the meaning of the term: Desiccant...


Design Capacity
The average daily flow that a treatment plant or other facility is designed t...

Find the meaning of the term: Design Capacity...


Design Value
The monitored reading used by EPA to determine an area's air quality status; ...

Find the meaning of the term: Design Value...


Designated Pollutant
An air pollutant which is neither a criteria nor hazardous pollutant, as desc...

Find the meaning of the term: Designated Pollutant...


Designated Uses
Those water uses identified in state water quality standards that must be ach...

Find the meaning of the term: Designated Uses...


Designer Bugs
Popular term for microbes developed through biotechnology that can degrade sp...

Find the meaning of the term: Designer Bugs...


Destination Facility
The facility to which regulated medical waste is shipped for treatment and de...

Find the meaning of the term: Destination Facility...


Destratification
Vertical mixing within a lake or reservoir to totally or partially eliminate ...

Find the meaning of the term: Destratification...


Destroyed Medical Waste
Regulated medical waste that has been ruined, torn apart, or mutilated throug...

Find the meaning of the term: Destroyed Medical Waste...


Destruction and Removal Efficiency DRE
A percentage that represents the number of molecules of a compound removed or...

Find the meaning of the term: Destruction and Removal Efficiency DRE...


Destruction Facility
A facility that destroys regulated medical waste.

Find the meaning of the term: Destruction Facility...


Desulfurization
Removal of sulfur from fossil fuels to reduce pollution.

Find the meaning of the term: Desulfurization...


Detectable Leak Rate
The smallest leak (from a storage tank), expressed in terms of gallons- or li...

Find the meaning of the term: Detectable Leak Rate...


Detection Criterion
A predetermined rule to ascertain whether a tank is leaking or not. Most volu...

Find the meaning of the term: Detection Criterion...


Detection Limit
The lowest concentration of a chemical that can reliably be distinguished fro...

Find the meaning of the term: Detection Limit...


Detention Time
1. The theoretical calculated time required for a small amount of water to pa...

Find the meaning of the term: Detention Time...


Detergent
Synthetic washing agent that helps to remove dirt and oil. Some contain compo...

Find the meaning of the term: Detergent...


Development Effects
Adverse effects such as altered growth, structural abnormality, functional de...

Find the meaning of the term: Development Effects...


Dewater
1. Remove or separate a portion of the water in a sludge or slurry to dry the...

Find the meaning of the term: Dewater...


Diatomaceous Earth Diatomite
A chalk-like material (fossilized diatoms) used to filter out solid waste in ...

Find the meaning of the term: Diatomaceous Earth Diatomite...


Diazinon
An insecticide. In 1986, EPA banned its use on open areas such as sod farms a...

Find the meaning of the term: Diazinon...


Dibenzofurans
A group of organic compounds, some of which are toxic.

Find the meaning of the term: Dibenzofurans...


Dicofol
A pesticide used on citrus fruits.

Find the meaning of the term: Dicofol...


Diffused Air
A type of aeration that forces oxygen into sewage by pumping air through perf...

Find the meaning of the term: Diffused Air...


Diffusion
The movement of suspended or dissolved particles (or molecules) from a more c...

Find the meaning of the term: Diffusion...


Digester
In wastewater treatment, a closed tank; in solid-waste conversion, a unit in ...

Find the meaning of the term: Digester...


Digestion
The biochemical decomposition of organic matter, resulting in partial gasific...

Find the meaning of the term: Digestion...


Dike
A low wall that can act as a barrier to prevent a spill from spreading.

Find the meaning of the term: Dike...


Diluent
Any liquid or solid material used to dilute or carry an active ingredient.

Find the meaning of the term: Diluent...


Dilution Ratio
The relationship between the volume of water in a stream and the volume of in...

Find the meaning of the term: Dilution Ratio...


Dimictic
Lakes and reservoirs that freeze over and normally go through two stratificat...

Find the meaning of the term: Dimictic...


Dinocap
A fungicide used primarily by apple growers to control summer diseases. EPA p...

Find the meaning of the term: Dinocap...


Dinoseb
A herbicide that is also used as a fungicide and insecticide. It was banned b...

Find the meaning of the term: Dinoseb...


Dioxin
Any of a family of compounds known chemically as dibenzo-p-dioxins. Concern a...

Find the meaning of the term: Dioxin...


Direct Discharger
A municipal or industrial facility which introduces pollution through a defin...

Find the meaning of the term: Direct Discharger...


Direct Filtration
A method of treating water which consists of the addition of coagulent chemic...

Find the meaning of the term: Direct Filtration...


Direct Push
Technology used for performing subsurface investigations by driving, pushing,...

Find the meaning of the term: Direct Push...


Direct Runoff
Water that flows over the ground surface or through the ground directly into ...

Find the meaning of the term: Direct Runoff...


Discharge
Flow of surface water in a stream or canal or the outflow of ground water fro...

Find the meaning of the term: Discharge...


Disinfectant
A chemical or physical process that kills pathogenic organisms in water, air,...

Find the meaning of the term: Disinfectant...


Disinfectant By-Product
A compound formed by the reaction of a disinfenctant such as chlorine with or...

Find the meaning of the term: Disinfectant By-Product...


Disinfectant Time
The time it takes water to move from the point of disinfectant application (o...

Find the meaning of the term: Disinfectant Time...


Dispersant
A chemical agent used to break up concentrations of organic material such as ...

Find the meaning of the term: Dispersant...


Displacement Savings
Saving realized by displacing purchases of natural gas or electricity from a ...

Find the meaning of the term: Displacement Savings...


Disposables
Consumer products, other items, and packaging used once or a few times and di...

Find the meaning of the term: Disposables...


Disposal
Final placement or destruction of toxic, radioactive, or other wastes; surplu...

Find the meaning of the term: Disposal...


Disposal Facilities
Repositories for solid waste, including landfills and combustors intended for...

Find the meaning of the term: Disposal Facilities...


Dissolved Oxygen DO
The oxygen freely available in water, vital to fish and other aquatic life an...

Find the meaning of the term: Dissolved Oxygen DO...


Dissolved Solids
Disintegrated organic and inorganic material in water. Excessive amounts make...

Find the meaning of the term: Dissolved Solids...


Distillation
The act of purifying liquids through boiling, so that the steam or gaseous va...

Find the meaning of the term: Distillation...


Disturbance
Any event or series of events that disrupt ecosystem, community, or populatio...

Find the meaning of the term: Disturbance...


Diversion
1. Use of part of a stream flow as water supply. 2. A channel with a supporti...

Find the meaning of the term: Diversion...


Diversion Rate
The percentage of waste materials diverted from traditional disposal such as ...

Find the meaning of the term: Diversion Rate...


DNA Hybridization
Use of a segment of DNA, called a DNA probe, to identify its complementary DN...

Find the meaning of the term: DNA Hybridization...


Dobson Unit DU
Units of ozone level measurement. measurement of ozone levels. If, for exampl...

Find the meaning of the term: Dobson Unit DU...


Domestic Application
Pesticide application in and around houses, office buildings, motels, and oth...

Find the meaning of the term: Domestic Application...


Dosage
1. The actual quantity of a chemical administered to an organism or to which ...

Find the meaning of the term: Dosage...


Dose Equivalent
The product of the absorbed dose from ionizing radiation and such factors as ...

Find the meaning of the term: Dose Equivalent...


Dose Rate
In exposure assessment, dose per time unit (e.g. mg/day), sometimes also call...

Find the meaning of the term: Dose Rate...


Dose Response
Shifts in toxicological responses of an individual (such as alterations in se...

Find the meaning of the term: Dose Response...


Dose Response Curve
Graphical representation of the relationship between the dose of a stressor a...

Find the meaning of the term: Dose Response Curve...


Dose-Response Assessment
1. Estimating the potency of a chemical. 2. In exposure assessment, the proce...

Find the meaning of the term: Dose-Response Assessment...


Dose-Response Relationship
The quantitative relationship between the amount of exposure to a substance a...

Find the meaning of the term: Dose-Response Relationship...


Dosimeter
An instrument to measure dosage; many so-called dosimeters actually measure e...

Find the meaning of the term: Dosimeter...


DOT Reportable Quantity
The quantity of a substance specified in a U.S. Department of Transportation ...

Find the meaning of the term: DOT Reportable Quantity...


Downgradient
The direction that groundwater flows; similar to "downstream" for surface water.

Find the meaning of the term: Downgradient...


Downstream Processors
Industries dependent on crop production (e.g. canneries and food processors).

Find the meaning of the term: Downstream Processors...


DP Hole
Hole in the ground made with DP equipment.

Find the meaning of the term: DP Hole...


Draft
1. The act of drawing or removing water from a tank or reservoir. 2. The wate...

Find the meaning of the term: Draft...


Draft Permit
A preliminary permit drafted and published by EPA; subject to public review a...

Find the meaning of the term: Draft Permit...


Drainage
Improving the productivity of agricultural land by removing excess water from...

Find the meaning of the term: Drainage...


Drainage Basin
The area of land that drains water, sediment, and dissolved materials to a co...

Find the meaning of the term: Drainage Basin...


Drainage Well
A well drilled to carry excess water off agricultural fields. Because they ac...

Find the meaning of the term: Drainage Well...


Drawdown
1. The drop in the water table or level of water in the ground when water is ...

Find the meaning of the term: Drawdown...


Dredging
Removal of mud from the bottom of water bodies. This can disturb the ecosyste...

Find the meaning of the term: Dredging...


Drilling Fluid
Fluid used to lubricate the bit and convey drill cuttings to the surface with...

Find the meaning of the term: Drilling Fluid...


Drinking Water Equivalent Level
Protective level of exposure related to potentially non-carcinogenic effects ...

Find the meaning of the term: Drinking Water Equivalent Level...


Drinking Water State Revolving Fund
The Fund provides capitalization grants to states to develop drinking water r...

Find the meaning of the term: Drinking Water State Revolving Fund...


Drive Casing
Heavy duty steel casing driven along with the sampling tool in cased DP syste...

Find the meaning of the term: Drive Casing...


Drive Point Profiler
An exposed groundwater DP system used to collect multiple depth-discrete grou...

Find the meaning of the term: Drive Point Profiler...


Drop-off
Recyclable materials collection method in which individuals bring them to a d...

Find the meaning of the term: Drop-off...


Dual-Phase Extraction
Active withdrawal of both liquid and gas phases from a well usually involving...

Find the meaning of the term: Dual-Phase Extraction...


Dump
A site used to dispose of solid waste without environmental controls.

Find the meaning of the term: Dump...


Duplicate
A second aliquot or sample that is treated the same as the original sample in...

Find the meaning of the term: Duplicate...


Dustfall Jar
An open container used to collect large particles from the air for measuremen...

Find the meaning of the term: Dustfall Jar...


Dynamometer
A device used to place a load on an engine and measure its performance.

Find the meaning of the term: Dynamometer...




Analytical testing dots