Annex VI, which came into force on 19 May 2005, governs the control of the discharge of noxious substances from ship diesels. It is applicable to ship diesels with a power larger than 130kW built and installed since 1 st January 2000.

MARSEC means Maritime Security as used by the U.S. Coast Guard to designate security levels.

The maximum allowable relief valve setting of a cargo tank, (IGC Code).

Mass is both a property of a physical body and a measure of its resistance to acceleration (rate of change of velocity with respect to time) when a net force is applied. An object's mass also determines the strength of its gravitational attraction to other bodies.

An illness preferably of an infectious nature affecting more than two persons on board at the same time.

In physics and engineering, mass flow rate is the mass of a substance which passes per unit of time.

Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions.

In physics, mass–energy equivalence is the relationship between mass and energy in a system's rest frame, where the two values differ only by a constant and the units of measurement.

The mass-to-charge ratio (m/Q) is a physical quantity that is most widely used in the electrodynamics of charged particles.

A tubular steel erection, which carries various items of navigational equipment and fittings, e.g. lights, radar, etc.

A controller, which is used in a cascade control system. It provides an output which acts as a variable desired value for a slave controller.

The interdisciplinary field of materials science, also commonly termed materials science and engineering, covers the design and discovery of new materials, particularly solids.

A materials property is an intensive property of some material, i.e., a physical property that does not depend on the amount of the material.

A mathematical model is a description of a system using mathematical concepts and language.

Matter is any substance that has mass and takes up space by having volume.

The greatest speed the ship is designed to maintain in service at sea at the deepest seagoing draught, (acc. to SOLAS, Chapter II-1, Part A).

Maximum Allowable Operating Pressure is a pressure limit set, usually by a government body, which applies to compressed gas pressure vessels, pipelines, and storage tanks.

Maximum allowable working pressure is defined as the maximum pressure based on the design codes that the weakest component of a pressure vessel can handle.

The maximum pressure of a piping system determined, in general, by the weakest piping component in the system or by the relief valve setting. The maximum allowable working pressure is not to exceed the design pressure.

The maximum continuous rated power output as specified on the nameplate and in the Technical File of the marine diesel engine.