TMA/DMFO. All outlets shall comply with the latest edition of NFPA 99
(reference 9r) and the requirements of Compressed Gas Association
Pamphlet V-5 (reference 9v).
Outlets for Non-Medical Function Use. The use of a central
medical gas system to serve an outlet that indirectly supports the
medical function such as in a laboratory may be justified. If so, the
branch piping and outlets shall be in accordance with NFPA 99 (reference
9r). Non-medical uses are not permissible except for unique
circumstances with documented waiver requests, coordinated with the Using
Service and Design Agent, reviewed individually.
Emergency Power Source. Life-critical medical gas system
equipment, requiring electrical power for generation, operation, or
alarm, shall be connected to an emergency power source. At the
discretion of the Design Agent, when requested by the Using Service,
dental compressed air, vacuum, and medical gas systems serving
anesthetizing treatment rooms in outpatient and dental treatment clinics
may be connected to an emergency power source. Refer to the Electrical
Section of this document for connection design guidance.
Medical Compressed Air (MCA). The MCA system shall be an
independent central piped system consisting of two or more medical air
compressors and a central receiver, all conforming to the requirements of
NFPA 99 (reference 9r). It shall be used only for medical functions
requiring breathable air to support respiration or for air-driven
instruments that discharge into the pharynx. The MCA system shall not be
used to satisfy any other compressed air requirements. The system design
shall include automatic operation of the compressors, including
alternating lead/lag status.
Air Quality Standards. The medical air compressor(s) shall
be specifically designed and manufactured for this purpose. MCA quality
shall be as defined in NFPA 99 (reference 9r). Intake air shall be
direct from outdoors or another source of equal or better quality located
in accordance with NFPA 99 (reference 9r). Designers are responsible to
size and show routing of medical air intake piping. MCA shall be
supplied at a minimum of 345 kPa (50 psig) at all outlets with a
tolerance of +35 kPa (5 psig).
General Requirements. MCA shall be provided by two or more
compressors with provisions for automatic, alternating, and simultaneous
operation. The compressors shall be sized such that if any one
compressor fails, the remaining compressor(s) shall provide 100% of
maximum system demand. Provide an alarm to indicate compressor failure
that annunciates at the master medical gas alarm panel. All system
components downstream of the compressors shall be sized for 100% standard
system demand and be duplexed. The receiver shall have an automatic drain
feature specified, since it is required to be upstream of the dryers in
accordance with NFPA 99.
Air Drying. System design shall include an air dryer of
either the mechanical refrigeration or desiccant type.
closely coordinate with the Using Agency for each project, to determine
whether operating conditions, facility maintenance capabilities, air
dryness limitations, or other factors favor preference of one type over
the other for the given application. Designers are responsible to
consider the following: