Commercial and Domestic Refrigerators
Commercial refrigerator and freezer units, which go by many other names, were in use for almost 40 years prior to the common home models. They used gas systems such as anhydrous ammonia (R-717) or sulfur dioxide (R-764), which occasionally leaked, making them unsafe for home use and industrial purposes. Practical household refrigerators were introduced in 1915 and gained wider acceptance in the United States in the 1930s as prices fell and non-toxic, non-flammable synthetic refrigerants such as Freon-12® (R-12) were introduced, however R-12 damaged the ozone layer, causing governments to issue a ban on its use in new refrigerators and air-conditioning systems in 1994. The less harmful replacement for R-12, R-134a (tetrafluoroethane), has been in common use since 1990, but R-12 is still found in many old systems today.
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Famous quotes containing the words commercial and, commercial and/or domestic:
“Electronic aids, particularly domestic computers, will help the inner migration, the opting out of reality. Reality is no longer going to be the stuff out there, but the stuff inside your head. It’s going to be commercial and nasty at the same time.”
—J.G. (James Graham)
“The cultivation of one set of faculties tends to the disuse of others. The loss of one faculty sharpens others; the blind are sensitive in touch. Has not the extreme cultivation of the commercial faculty permitted others as essential to national life, to be blighted by disease?”
—J. Ellen Foster (1840–1910)
“Let me obtain forgiveness of thee, Samson,
Afford me place to shew what recompence
Towards thee I intend for what I have misdone,
Misguided; only what remains past cure
Bear not too sensibly, nor still insist
To afflict thy self in vain: though sight be lost,
Life yet hath many solaces, enjoy’d
Where other senses want not their delights
At home in leisure and domestic ease,”
—John Milton (1608–1674)