Commercial
Consumer Info
A building's heating, ventilation,
and air conditioning (HVAC) system provides conditioned air to
occupied spaces within the facility. Typically, air from within an
occupied space, along with fresh air drawn from outdoors, in drawn
in through ductwork to an HVAC unit, where it is conditioned. Before
the air gets to the unit, it usually passes through a filter
designed to protect the mechanical equipment from becoming
contaminated by large particles of dust and debris. Many filters
commonly used today will not prevent the introduction of small
particles of dust and debris from the air stream into the system.
Over time, these deposits may form sizable accumulations.
In the course of normal building
operations, the humidity level within the HVAC system can vary
greatly. High humidity can combine with dust and debris in the
system, often resulting in the growth of microbial contamination. In
an HVAC system, microbial contamination (such as mold, fungus and
their spores) may cause adverse health reactions among building
occupants. Condense drain pans and other system components often
become heavily contaminated with fungal and bacterial slime.
In order to maintain acceptable
indoor air quality (IAQ) it is commonly recommended that mold,
fungi, dust and other contaminants are cleaned out of the HVAC
system. Cleaning HVAC systems provides many benefits. Cleaning
lessens the likelihood of indoor air pollution in the building, and
may help to alleviate health and comfort complaints by occupants.
Clean HVAC systems perform more efficiently, which may decrease
energy costs. Well maintained mechanical components are likely to
last longer, reducing the need for costly HVAC system replacement or
repairs.
With growing awareness of the
dangers of indoor air pollution, public concern for the cleanliness
of ventilation systems has led to significant increase in demand for
HVAC system cleaning services. Solving complex IAQ problems,
however, often requires a team of multi-disciplined professionals,
such as mechanical contractors, filtration experts, test and balance
specialists, industrial hygienists, and, of course, professional
HVAC system cleaning contractors.
In most cases, HVAC system cleaning
alone will not solve IAQ problems. It can, however, greatly reduce
the threat of indoor air pollution when performed in conjunction
with a program of regular building maintenance and IAQ evaluation.
The U.S. Environmental Protection Agency (EPA) has published a
comprehensive guide for building owners and managers which is
designed to help reduce the risk of indoor air pollution. The
publication, "Building Air Quality," (provide link) provides
guidelines which all owners and managers should use and implement in
their facilities.
There are several ways to clean an
HVAC system. Recommended cleaning methods employ "Source Removal,"
the mechanical cleaning of system components to remove dirt and
debris. Source removal methods employ vacuum units, compressed air,
mechanical and hand brushes, and other tools to loosen dirt and
debris and convey it to a containment device for proper disposal.
Source removal requires two key
elements to be effective. The first element is a means of agitating
the dust and debris within the HVAC system. The second element is
the extraction of contaminants from the HVAC system. Removal methods
must be capable of removing the foreign material to the levels
specified within industry standards.
Air duct cleaning services have
been available since the early 1900s. By the early 1970s, hundreds
of air duct cleaning companies were thriving in America. The
problem, however, was that many of these companies were utilizing
inferior methods of cleaning. Often they applied chemical
encapsulants or dust abatement products over contaminants in air
ducts to restrict the movement of these particles and render them
"harmless" to building occupants. However, many such products were
not proven safe for use in air handling systems.
In February of 1989, a group of air
duct cleaning professionals banded together to help educated the
public about the need for properly performed HVAC system cleaning
services. They formed the National Air Duct Cleaners Association (NADCA),
and made it their goal to promote Source Removal methods of HVAC
system cleaning.
Today, NADCA is represented
throughout the United States, and also has a substantial
international membership. NADCA's involvement in programs held by
the U.S. EPA, American Society of Heating, Refrigeration and
Air-conditioning Engineers (ASHRAE), National Coalition on Indoor
Air Quality (NCIAQ), and other environmentally conscious public and
private sector organizations will help the association continue to
be the leading authority in HVAC system cleaning.
Introduction to HVAC System
Cleaning Services-A Guideline for Commercial Consumers is a
comprehensive overview of HVAC system cleaning. Chapters include
contaminants, indoor air quality, site preparation, equipment,
chemicals, safety, and much more.
Published as the "Introduction"
from "Introduction to HVAC System Cleaning Services: A Guideline
for Commercial Consumers." National Air
Duct Cleaners Association, Inc. (NADCA).
Commercial HVAC System
Cleaning in Houston