damp


Also found in: Dictionary, Thesaurus, Medical, Legal, Acronyms, Idioms, Wikipedia.
Related to damp: dampen

damp,

in mining, any mixture of gases in an underground mine, especially oxygen-deficient or noxious gases. The term damp probably is derived from the German dampf, meaning fog or vapor. Several distinct types of damp are recognized. Firedamp is methanemethane
, CH4, colorless, odorless, gaseous saturated hydrocarbon; the simplest alkane. It is less dense than air, melts at −184°C;, and boils at −161.4°C;. It is combustible and can form explosive mixtures with air.
..... Click the link for more information.
 and other flammable gases, often mixed with air; it results from the decomposition of coal or other carbonaceous materials. Explosive mixtures of firedamp with air usually contain from 1% to 14% methane. The mixture of gases that remains after a firedamp explosion is called afterdamp; it consists chiefly of carbon dioxide and nitrogen. Chokedamp is any mixture of oxygen-deficient mine gases that causes suffocation. (In England, carbon dioxide is called chokedamp.) Several methods are used for detection of damps. The Davy safety lampsafety lamp,
oil lamp designed for safe use in mines and other places where flammable gases such as firedamp (see damp) may be present. Its invention (c.1816) is usually attributed to Sir Humphry Davy.
..... Click the link for more information.
 is one of the earliest detection devices. The color and height of the lamp flame indicate the amount of firedamp present; if the flame is extinguished, chokedamp is present. Canaries were formerly kept in mines; the birds are overcome by relatively small quantities of noxious gases, and their death warned the miners of the presence of damps. Special colorimetric detectors are now used. The methanometer is a special portable instrument used to detect firedamp.

damp

[damp]
(engineering)
To reduce the fire in a boiler or a furnace by putting a layer of damp coals or ashes on the fire bed.
(mining engineering)
A poisonous gas in a coal mine.
(physics)
To gradually diminish the amplitude of a vibration or oscillation.
References in periodicals archive ?
If you answer yes to these questions, you've probably got damp.
These extract the damp from the room - a good one (and the cheapest may not be best) costs about PS400.
The company says a watertight, low-profile sheet membrane solution to the problem of persistent damp, Drybase Flex Membrane is a highly durable and flexible means of protection against moisture ingress.
If it is damp, the paint will bubble as the moisture tries to escape and you will need to contact a damp-proof specialist - good to avoid if you can as they are expensive.
Dealing with any damp and condensation in your home, avoiding damp buildings, damp woods and rotten leaves, cut grass and compost heaps.
Firstly, damping torque analysis is applied to prove that FESS has the ability to damp the multi-mode oscillation.
THIS one's straight from my Gran: if you wipe down your bathroom mirror with a damp cloth and washing up liquid and let it dry, she promises me it will stay clear for a month.
Not only is living in a home with a damp problem unpleasant it is also very bad for your health.
If your home doesn't have a damp-proof course, or it's defective, you'll need a damp specialist to install one.
And while everyone knows the benefits of damp proofing, people tend to think about the mess of replastering that usually comes with a new damp proofing course.
The musty smell is caused by fungal growth, so you may have to scrub the walls, replace damp boxes, and wash or throw out musty-smelling items.