Terms starting with E

A lightweight saw that cuts control joints within hours of finishing, before shrinkage cracks can start.

Fault in which a live conductor makes unintended contact with earth or with earthed metalwork.

Total impedance of the path a fault current takes from the source, through an earth fault and back again.

Arrangement describing how a supply's neutral and an installation's exposed metalwork are connected to earth.

Shop name for a spiral screw extractor driven backward into a drilled broken bolt to unscrew it. Shop talk

Tidal current running out toward the sea and down rivers and estuaries, mostly while the water is falling.

Describes an estuary or inlet where ebb currents are stronger than flood currents, pushing sediment seaward.

Emergency core cooling system: the set of safety systems that inject water to keep the core covered after a loss of coolant.

Electronic Chart Display and Information System: the type-approved chart system a ship can carry in place of paper charts.

Dampers and controls that bring in cool outdoor air for free cooling instead of running compressors.

Erbium-Doped Fiber Amplifier: the optical amplifier that boosts signals near 1550 nm without converting them to electronics.

Tooth load piling up at one end of the face width because of misalignment or deflection.

Adhesive squeezing out from the sides of a tape roll or die-cut part, making edges sticky and dirty. Shop talk

Strips cut from both sides of a nonwoven web to give clean edges and the correct finished width.

A hand tool that rounds and compacts the edges of a slab along its forms so they resist chipping.

Equivalent direct radiation: the square-foot rating of heating radiators, used to size steam boilers.

Energy efficiency ratio: cooling output in Btu per hour divided by watts of input at one hot, full-load test point.

Depth below the surface where hardness falls to a set value, usually 50 HRC, on a case-hardened part.

A whole-body dose figure that adds up organ doses weighted by each tissue's sensitivity to radiation risk.

The pumping speed actually delivered at the chamber after losses in the connecting pipes and valves.

The white powder or crust that appears where water seeps out of concrete or masonry and leaves its salts behind.

White crystalline salt deposits left on masonry or concrete as water moving through it evaporates.

Film regime in rolling contacts where huge pressure stiffens the oil and elastically flattens the metal.

A fitting that changes the direction of a pipe run, usually by 90 or 45 degrees.

Electronic leak detection, using a small electric current to pinpoint breaches in a membrane.

Filter fabric, usually meltblown, carrying a long-lasting electrostatic charge that pulls particles out of the air.

Washboard pattern on bearing races caused by electric current arcing through the rolling contacts.

Conductive medium such as soil, seawater or concrete pore water that carries ionic current between anode and cathode.

Spraying charged powder at a grounded part so electrical attraction pulls it on and holds it until cure.

Spectrometric measurement of wear metals, contaminants and additive elements in oil, in parts per million.

Blast furnace hearth wear profile where the wall-to-floor corner erodes into the shape of an elephant's foot. Shop talk

Electrical leak location: surveys that find holes in an installed geomembrane by tracing current through them.

Abrasive particles left stuck in the substrate after blasting, visible at the bond line in a cross section.

Preload lost soon after tightening as surface roughness under the head, nut and threads flattens out.

Steel plates, anchor bolts, sleeves and inserts cast into concrete for connections made later. Shop talk

Pressing a raised or recessed pattern into a nonwoven with engraved, usually heated, rolls.

Electromagnetic compatibility: a product neither upsets nearby equipment with its noise nor gets upset by theirs.

The graded levels used to declare a nuclear plant emergency, each triggering a defined response.

Electromagnetic interference: unwanted electrical noise that disturbs the operation of a circuit or system.

Electrical metallic tubing: thin-wall, unthreaded steel conduit joined with set-screw or compression fittings.

A score comparing a lab's result with a reference value, scaled by both expanded uncertainties; 1 or less passes.

Electronic navigational chart: an official vector chart database used in ECDIS, built from objects with attributes.

An upturned end at the termination of a flashing that stops water from running off the end into the wall.

A dump truck or trailer that raises its bed and unloads out the tailgate, the standard way to feed a paver. Shop talk

The polished tip of a connector ferrule and fiber, where light leaves one fiber and enters the next.

A rotating cutter with teeth on its end and sides, the main tool for milling slots, pockets and profiles.

A carrier atmosphere of carbon monoxide, hydrogen and nitrogen made by reacting natural gas with air.

Electroless nickel immersion gold: flat surface finish of nickel topped with a very thin layer of gold.

The total heat content of moist air, sensible plus latent, in Btu per pound of dry air.

End-of-train device: a unit hung on the last car's coupler that reports rear brake pipe pressure and motion to the head end.

Extreme pressure: additives or oils that react with metal under heavy load to prevent welding and scuffing.

Electronic personal dosimeter: a worn device that shows dose and dose rate live and alarms at set points.

A thermoset adhesive cured by reacting epoxy resin with a hardener, the benchmark for strong, rigid structural bonds.

The field termination method of gluing fiber into a connector and polishing the end face by hand.

Powder based on epoxy resin, prized for chemical and corrosion resistance but weak in sunlight.

Emergency planning zone: the area around a nuclear plant where protective actions are pre-planned.

Describes a valve characteristic where each equal step of travel changes flow by the same percentage of current flow.

The theoretical tide an ocean covering the whole Earth would show if it responded instantly to the tidal forces.

Connecting metal parts together so they sit at one potential and no dangerous voltage appears between them.

Absorbed dose to an organ multiplied by a weighting factor for the type of radiation, measured in sieverts.

Electrical resistance probe that tracks corrosion by measuring the rising resistance of a thinning metal element.

Three-piece union that joins two lengths of threaded rigid conduit when neither one can be turned. Shop talk

Accelerated metal loss where flowing fluid strips protective films and corrosion follows, often at bends and tees.

The signed difference between a measured value and the reference value of the quantity being measured.

Ellipsoidally referenced survey: depths taken from GNSS ellipsoid heights and converted to chart datum with a separation model.

Energy recovery ventilator: a unit that swaps heat and moisture between outgoing exhaust air and incoming fresh air.

Electrostatic discharge: sudden flow of built-up static charge that can destroy or upset electronics.

Synthetic or natural base oil made from acids and alcohols, valued for solvency, film strength and biodegradability.

A pair of parallel reflecting surfaces that transmits a comb of sharp frequency peaks, used to select or measure wavelengths.

Chemical removal of unwanted copper from a board, leaving only the protected circuit pattern.

A film-forming liquid sprayed on fresh concrete to slow moisture loss between finishing passes.

The coil or heat exchanger where low-pressure liquid refrigerant boils off, absorbing heat from air or water.

Any point on an OTDR trace where the signal departs from the smooth fiber slope, such as a splice, connector or break.

The distance after a reflective event during which an OTDR cannot detect a second, separate event.

Exponentially weighted moving average: a chart or controller that blends each reading with the past to catch small, slow shifts.

Combustion air supplied beyond the exact amount needed to burn all the fuel, expressed as a percentage.

The strictest survey order, used for berths and critical channels where under-keel clearance is minimal.

Sudden departure of yield, defect counts or a key parameter from its normal band, big enough to trigger holds and an investigation. Shop talk

The heat released by a curing adhesive, which speeds the reaction and can overheat thick masses.

Combined standard uncertainty multiplied by a coverage factor to give an interval with a stated coverage probability.

Gap deliberately left in a lining so bricks or castable can grow with heat without crushing or lifting.

A designed gap between building elements that lets them move with temperature, settlement and load without cracking.

A closed tank with an air cushion that absorbs the expansion of heating water as it warms up.

Violent failure of a castable during first heat-up when trapped steam pressure blows the lining apart.

Being subjected to ionising radiation, from outside the body or from material within it.

A roster of crew members with no regular job, called in rotation to fill vacancies and extra trains. Shop talk

Geomembrane seam made by laying a bead of molten polymer along the edge of an overlap, used for patches and details.

Joking name for measuring by eye, the calibrated eyeball used when no real gauge is handy. Shop talk