Natural refrigerants are substances that serve as refrigerants in refrigeration systems.

Natural resources are resources that exist without any actions of humankind.

Natural uranium refers to uranium with the same isotopic ratio as found in nature. It contains 0.711% uranium-235, 99.284% uranium-238, and a trace of uranium-234 by weight (0.0055%).

Natural-gas condensate, also called natural gas liquids, is a low-density mixture of hydrocarbon liquids that are present as gaseous components in the raw natural gas produced from many natural gas fields.

A map of water area including the adjoining land, intended primarily for use of mariners.

Distance of one minute of longitude at the equator, equal to 1852m.

The science and practice of designing ships as distinguished from their construction which is covered to shipbuilding.

The main workstation on the bridge where speed and course are considered and controlled, preferably conceived for working in the seated position with optimum visibility and integrated presentation of information and operating equipment.

All tasks relevant for deciding, executing and maintaining the course and speed in relation to waters and traffic.

Magnetic compass, gyrocompass, radar, echo sounder, rudder angle indicator, propeller revolution counter, rate of turn indicator.

A vessel intended for buoy handling.

All seagoing ships must be equipped with running and signal lights in compliance with the International Regulations for Preventing Collision at Sea (COLREG).

The person navigating, operating the bridge equipment and manoeuvring the ship.

An international maritime radio telex system sponsored by IMO and IHO, which automatically receives the broadcast telex information such as navigational, meteorological warnings and search and rescue (SAR) alerts on 24-hour watch basis.

Near-isothermal compression (and expansion) is a process in which a gas is compressed in very close proximity to a large incompressible thermal mass such as a heat absorbing and releasing structure (HARS) or a water spray.

A term describing local corrosion at junction of plating and stiffeners due to flexure effects caused by reverse, cycling loading with loss of coating or shedding of scale exposing fresh steel to further corrosion.

To efficiently wind the pole shoes lying close together of electronically commutated multipole three-phase motors, they will be coated with insulation and directly wound with the needle winding method.

Negative energy is a concept used in physics to explain the nature of certain fields, including the gravitational field and various quantum field effects.

Negative geothermal gradients occur where temperature decreases with depth.

Stainless steel net cutters are mounted on the rope guard, overlapping the propeller hub.