Heating, Ventilation, and Air Conditioning (HVAC) Systems
The major compliance concern associated
with HVAC systems involves refrigerant fluids. The types of fluids
used in older systems, chlorofluorocarbons, or CFCs, belong to a class of
chemicals called ozone depleting substances (ODSs).
Although CFCs are safe if handled properly, and are non-toxic,
they have a deadly side-effect. When released into the atmosphere, these
highly stable compounds slowly diffuse up to the stratosphere, where they are
broken down by ultraviolet light (UV) from the sun. Each molecule of
gas breaks down into forms of chlorine and other compounds, and starts a chain
reaction during which many molecules of ozone are destroyed. A little
CFC goes a long way in ozone destruction.
Ozone is a form of oxygen that is produced by reactions
involving other molecules and ultraviolet light. This reaction can occur
throughout the atmosphere. When it happens at ground level, it is a problem
for us -- ozone attacks the lungs. But in the stratosphere, where ultraviolet
light is more intense, the formation of ozone is beneficial to us. Ozone
absorbs the ultraviolet sunlight before it reaches the earth's surface. If
the ozone is depleted, our eyes and skin experience a higher level of this
high-energy light, causing conditions such as cataracts, as well as skin damage
that sometimes leads to cancer. Many other living species in the environment
are also damaged by high UV levels.
January 2009. EPA published on Jan. 2, 2009 a Determination of Acceptability that expands the list of acceptable substitutes for ozone-depleting substances under the U.S. Environmental Protection Agency's (EPA) Significant New Alternatives Policy (SNAP) program. The determinations concern new substitutes for use in the refrigeration and air conditioning, fire suppression and explosion protection, and foam blowing sectors. (read Federal Register Notice)
December 2008. EPA is proposing to ban the sale or distribution of air- conditioning and refrigeration appliances containing HCFC-22, HCFC-142b, or blends containing one or both of these substances, beginning January 1, 2010. In addition, EPA is proposing to extend these requirements to air-conditioning and refrigeration appliances that are suitable only for use with newly produced HCFC-22, HCFC-142b, or blends containing one or both of these controlled substances as the refrigerant, and pre-charged appliance parts. (see Federal Register notice)
Veterinary facilities are required
to prevent further damage to the earth's protective stratospheric ozone
layer by preventing releases of ODSs from their HVAC systems. These
releases can occur during normal operation if the system is not properly
checked and maintained. They can also occur during servicing.
The best way to ensure that an HVAC system minimizes its
releases of ODSs during normal operation is to use refrigerants that have an
inherently low ozone depleting potential. The production of CFCs was
phased out by 1996. But CFCs continue to be used in pre-existing systems.
Some facilities have replaced the CFCs in their systems
with a compromise alternative refrigerant type, called hydrochlorofluorocarbons
(HCFCs). They are less stable than CFCs, and are more likely to break
down before they reach the stratosphere, and are thus weaker as ODSs than CFCs. But
they still damage the ozone layer. The production of HCFCs is being gradually
phased out over the next several years.
Please note that HCFCs, like all refrigerants, can be toxic
if exposure levels exceed recommended practices. For all chemicals, users should
follow the precautions set forth in Material Safety Data Sheets provided by
the chemical manufacturer, as well as other safety practices and standards
such as ASHRAE Standard 15 (this standard is available
for purchase from ASHRAE).
that are both CFC- and HCFC-free are now available. To ensure future
compliance, your facility should either verify that all
refrigeration and air conditioning equipment already runs on CFC
free and HCFC free gas, or should begin the conversion process now.
Servicing should be performed by certified technicians only. Facilities
may want to verify that HVAC contractors employ technicians certified by NATE
(North American Technician Excellence), the leading industry-supported
testing and certification program.
EPA provides an information
page on technical certification programs.
The following professional organizations may be able to
provide additional information:
Regulations require that HCFCs and CFCs in discarded equipment
are properly captured to avoid release into the environment. (This also
applies to alternative fluids such as HFCs.) EPA provides an information
page listing EPA-certified refrigerant reclaimers.
Pollution Prevention Opportunities
Building design can substantially
reduce the need for air conditioning.
HVAC units should be converted to use alternative
refrigerants that are both CFC- and HCFC-free.
HVAC units should be properly sized, and should be selected
for high efficiency. More information is available from the Energy
Star healthcare index page.
Refrigerant Recycling Rule
The purpose of section 608 of the Clean
Air Act (CAA) is to minimize the quantity of refrigerants released to the atmosphere,
and to maximize the recovery and recycling of refrigerants during the servicing
and disposal of stationary air conditioning and refrigeration equipment. Requirements
include technician certification, mandatory use of recovery and recycling equipment,
and service practices that minimize refrigerant emissions, prohibition
of venting, service requirements, equipment certification, leak repair, proper
disposal, and recordkeeping. More information can be found at http://www.epa.gov/region02/cfc/,
and at http://www.epa.gov/ozone/title6/608.
Cooling towers, which can be part of cooling and refrigeration
systems, must not use hexavalent chromium water treatment chemicals. The use
of hexavalent chromium in comfort cooling towers was banned under a 1990 rule
under the Toxic Substances Control Act.
The Stratospheric Ozone Information Hotline, at 800-296-1996,
or the Ozone Depletion web site (www.epa.gov/ozone),
provides general information about regulations promulgated under Title VI of
The EPA IAQ
Building Education and Assessment tool (I-BEAM) contains comprehensive
state-of-the-art guidance for managing indoor air quality in commercial buildings.
There is a contents
box specifically for material on HVAC systems.
Star For Healthcare index page provides links to energy conservation information
selected for relevance to the healthcare sector.
EPA provides an information
page with links for businesses that use ozone depleting substances.