|Home | Fire
Safety | Skyscrapers
Home Emergencies | Glossary
Masking noise: Noise intentionally introduced into an environment in order to make certain noises less obtrusive, or to make conversations more private.
Masonry: Brickwork, stonework, or concrete blockwork.
Mastic: A substance that is semi-liquid, viscous, and sticky.
Mat foundation: See Foundation, mat.
Mean radiant temperature (MRT): The weighted average of the temperatures of all the objects that exchange thermal radiation with a given point.
Membrane roof: A low-slope roof that is made waterproof by a single sheet of impervious material.
Monitor: A boxlike protrusion above a roof that contains windows and /or ventilating louvers.
Mortar: The substance used between masonry units as a cushion, spacer, shim, adhesive, and sealant.
MRT: See Mean radiant temperature.
Neutral wire: A wire that is connected to ground.
Night blindness: An inability to see in darkness immediately after leaving a much brighter environment, due to the time that it takes the eye to adjust from one level of illumination to another.
Night-sky radiation: Long-wave infrared radiation from terrestrial objects into space.
Night soil: Human excrement.
Noise: Unwanted sound.
Nosing: The projecting front edge of a stair tread.
One-way: Structural action in a slab or plate that takes place only in one principal direction.