A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
UNITARY SYSTEM: A room unit which performs part
or all of the air conditioning functions. It may
or may not be used with a central fan system.
UPPER EXPLOSIVE LIMIT (UEL): The highest concentration
(expressed in percent vapor or gas in the air
by volume) of a substance that will burn or explode
when an ignition source is present.
UREA FORMALDEHYDE FROM INSULATION (UFFI): a form
of insulation no longer in use because of excessive
formaldehyde emissions and documented associated