Airborne
Allergens
The
World Health Organization considers the term allergy to mean an acquired
specific altered capacity of an individual to react in a different enhanced
way upon re-exposure to a particular agent. Airborne allergens are to
be found in most office and residences. The response of occupants to
a specific antigenic trigger is primarily due to their particular individual
immune status. Indoor antigens include dust, mites, molds, decaying
organic matter, pets, yeast, bacteria, formaldehyde epoxy resins, flour
and food dusts.
Bacteria
Airborne
bacteria and viruses are frequently found in indoor air and may represent
a significant health risk. These micro organisms can carry infectuous
diseases such as influenza and legionnaires’. Legionnaires’ is caused
by the legionalla family of bacteria which thrives in moderately high
temperatures (100o F) and is found in water tanks, humidifiers and cooling
towers. Infection is produced by inhalation.
Bioaerosols
A bioaerosol
is something airborne, which is a living thing, was living, or was a
product of something living. Some bioaerosols are human dead skin flakes,
viruses, bacteria, mold sprores, algae, yeasts, protozoa, pollen, dust
mite, allergens, car and dog allergens, human and animal dander, etc.
All of these bioaerosols can affect people's health.
Biodeterioration/Mold
Severe
water or moisture damage to buildings often results in significant fungal
contamination. This contamination can present hazardous exposure conditions
to occupants. It also damages (biodeteriorates) building materials and
furnishings.
The materials
that are most susceptible to biodeterioration are those that are porous,
such as cellulose-covered wallboard, fibrous insulation materials, ceiling
tiles and textiles. The sustained growth of any fungus indoors can present
a health risk to building occupants. The sustained growth of toxigenic
fungi presents the greatest risk. Preliminary identification or confirmation
of the type(s) of mold (species) present is helpful for devising a remediation
plan. Qualitative microscopic examination of settled dust or contaminated
materials can provide this information. If visible contamination is
not observed, measuring microbial volatile organic compounds (MVOCs)
can provide a useful surrogate indicator of growth. MVOC analysis can
help determine the presence of microbial growth which may not be visibly
accessible, such as in air plenums or within wall cavities. Follow-up
sampling after completion of remediation activities is useful in determining
the effectiveness of clean-up efforts.
If porous
materials or products are visibly moldy or water-soaked, proper disposal
is required. Interior surfaces that are not porous may be cleaned using
a combination of damp wiping, HEPA-vacuuming and local application of
disinfectants. If a toxigenic fungus such as Stachybotrys visually contaminates
a porous surface, cleaning is not recommended; disposal is the most
sensible option. Also keep in mind that mold spores may have become
dispersed into areas that were not directly affected by water damage.
As a result, sampling and remediation efforts may need to be extended
beyond the obvious visibly-contaminated areas.
Mold-contaminated
materials should be isolated during handling, using containment enclosures
maintained under negative pressure relative to non-contaminated areas.
Careful handling is critical, so as not to further disperse mold spores.
Once a person develops a respiratory problem caused by mold, they are
sensitive to mold forever. Personal protective equipment (PPE) needed
includes, at a minimum, protective clothing and a properly fitted respirator
equipped with high efficiency filters.
Examples
of these areas are:
-
Condensation
in wall cavities or wall spaces where the vapor barrier is placed
on the incorrect side of an outer wall allowing moisture to condense
inside the vapor barrier but on the back side of the inside wall.
-
Moisture
condensing on supply diffusers as the dew point of the room air
is above that of the supplied air. Condensation on windows that
runs down the window and collects in induction unit housings or
in wall cavities underneath the windows.
-
Condensation
on refrigerant lines where they are not adequately insulated or
the liquid refrigerant line is running through the supply air distribution
system.
-
Condensate
drain pans that are not adequately maintained or are not drainage
properly.
-
Moisture
by passing the coil due to improper coil sizing, improper maintenance
of the coil, or improper design.
-
Carpet
cleaning where too much water is left in the carpet after cleaning.
-
Engineering
design or modifications where the configurations in the air distribution
system allow for moisture to be present on certain areas of the
system and at a certain time of the week.
-
Utilization
of unsealed concrete block in air distribution systems which allows
moisture to penetrate and therefore become retained in the block.
-
Moisture
intrusion from unsealed concrete primarily in basements where the
water table or the exterior part of the wall can become saturated.
-
Improper
installation of attic insulation causing condensation between the
insulation and the underside of the roof.
In all
of the above areas, the primary reason for moisture tends to be improper
design or improper maintenance of the building and/or ventilation
system.
Types
of Remediation
There are four basic types of ventilation remediation when dealing
with invisible microbial contamination: cleaning, sanitizing, encapsulating
and ozonation (the use of ozone). While each type of method has its
benefits and limitations, probably the most important consideration
is the subjective interpretation of these terms by the industrial
hygienist, building owner, and the remediation contractor. This is
significant in light of the absence of any definition of terms, measurements
of total results, warranty claims, lack of access for verification
and quality control during remediation.
Guidelines
for industrial workplaces
40-60 % RH - Summer
20-50% RH - Winter
Mold
odors often characterized as "dirt, mushroom, or musty"
result from the release of mold specific chemicals known as microbial
volatile organic compounds or MVOC's. Research as shown that these
chemicals may contribute to adverse human health effects.
Carbon
Dioxide
Indoor
carbon dioxide concentrations are typically higher indoors than outdoors.
Carbon dioxide is an exhaled byproduct of a mammalian metabolism. In
office buildings and school structures occupied by multitudes, carbon
dioxide concentrations will rise as the day progresses and peak in the
late afternoon. Carbon dioxide concentrations have therefore served
as a useful index compound to quickly and easily assess the effective
ventilation rate of a structure. In general it is commonly accepted
that afternoon carbon monoxide concentrations less than one thousand
parts per million should be associated in most cases with an acceptable
supply of outside air.
Carbon
Monoxide
Carbon
monoxide (CO) is formed from incomplete combustion of burner fuel and
the partial oxidation of evaporated ink oils and solvents as they pass
through a burner. Flame carbon monoxide is controlled because of its
adverse effects on human health. It is well known that high concentrations
of CO are fatal; however, even very low concentrates of CO in the atmosphere
can cause respiratory distress. Other sources of carbon monoxide in
metropolitan areas range from automobiles and home furnaces.
Dust
and Particles
The
human body filters out dust and particles in the 10 micron plus range
through the upper respiratory tracts. Particles in the 10 micron and
less range can reach the lungs and cause multiple problems. Particles
in the 0.3 micron range most easily enter the respiratory system and
require true HEPA filtration for removal. By eliminating and controlling
the level of dust and other particles through high efficiency filtration,
building air quality standards can be achieved and maintained.
Particles
we breathe
Environment particle counts (P/CF 70.3 microns)
Urban
ambient: 200,000 - 2,000,000 +
Office environment: 100,000 - 1,000,000 +
Hospital surgery room: 50,000 - 500,000
Clean room (typical): 10 - 100
Clean room (advanced): 0.1 - 1
Industrial
Workplace Standards
0.2
mg/m3 (0.1 PPM) 8 hr TWA EPA
100 4G/M3 - 1 hr short term
40 4G/M3 Long term
Energy
Management
Reduced energy bills are one of the
benefits of a proper balanced cleaned HVAC system.
Causes
of energy loss are not always apparent.
Example:
-
The
environmental protection agency reports that 1/24 inches of dirt on
a coil will decrease its efficiency 21%.
- Dirty
duct systems can increase fan amperages up to 10%.
- Duct
leakage may account for losses up to 25%.
- Dirt
on fan blades will seriously reduce their efficiency.
- Scaling
- The ground water we use is comprised of soluble calcium bicarbonate
(CaHCO3) and other assorted particulate which
is in suspension. Unfortunately,once the ground water enters a building's
water pipe system, and the water becomes heated, a series of changes
unfold; most of which cause problems. The once soluble calcium bicarbonate
converts to the insoluble calcium carbonate (CaCO3)
some of which precipitates out immediately seeding itself on the walls
of the pipe. The higher the heat, the more activity there is: consequently
the crystalline calcite scale accumulates. Scale build-up in
boilers translates into lower heat transfer (more cost to heat the water)
as well as the potential to overheat the metal surfaces, causing parts
to fail. In addition, corrosive deterioration often occurs due to the
electrolysis that happens between the scale and the metal.
- Corrosion
is one of the most costly problems associated with water process systems,
especially where steam is associated. There are two distinct changes
taking place which cause problems. The first of these is the reaction
of the metal and the water itself. When water splits into its components,
it produces an excess of free oxygen and hydrogen which in their atomic
states are ionic and more reactive. The free hydrogen ions cause metal
embrittlement, which is accelerated by elevated temperatures. This is
readily observable in tube bundles, steam heat exchangers and process
equipment. The excess oxygen oxidizes and rusts out the equipment.
The
lack of proper pressure relationships creates irregular airflow to building
occupants who respond by adjusting thermostats beyond normal settings
and economical set points. This results in systems working longer and
harder adding to costs and early mechanical failure.
Formaldehyde
Formaldehyde is a colorless volatile gas with a characteristic
odor. It is highly soluble in water and is irritating to the eyes and
nucuous membranes. Formaldehyde is a useful manufacturing intermediary
that has important roles in chemical processes and the manufacturing
of press board, plywood and resins. Formaldehyde can also be generated
during combustion processes such as tobacco burning or space heating
in both environmental and manufacturing settings. It has been recognized
that allergic sensitization to formaldehyde can occur. i.e.. asthma,
immunoneurological reactions.
O.10 PPPM
Action level (Canada)
0.05 PPPM Target level
Lead,
Dust and Fumes
Airborne
lead concentrations arise from combustion or organic lead compounds
in fuels smelting and mining. Indoor concentrations are derived primarily
from outdoor supply air. A small contribution may occur from indoor
lead paint pigments, reentrained into the air stream with duct particles.
Lead exposures can result during renovation, remodeling or construction
activities that result from disturbing paints and finishes that contain
lead pigments.
Remediation
These toxic metal particulates can be controlled by local ventilation
capture utilizing HEPA filters.
Industrial
Work Place Standards
o.15 MG/M3 8 hr TWA
Man
Made Mineral Fibres
MMMF
represents synthetic fibrous materials composed of fiberglass, mineral
wool, slag wool and ceramic, refractory fiber that have been used for
thermal and acoustical insulation purposes.
MMMF can
cause mechanical irritation to the skin, eyes and upper respiratory
tract.
Moisture
Moisture
intrusion in the micro-environment of a commercial building is considered
one of the primary contributors of undesired microbial growth. While
a certain amount of bacteria and fungi can and should be one of the
signs for a healthy environment, the overabundance of colonization on
surfaces in a building has become a reason for concern.
Aside from
moisture, other necessary conditions for bacterial growth or fungal
growth are temperature ranges that will allow growth a nutrient or food
source for microbial growth, and the presence of microorganisms. All
three of these conditions are present in a building with the two varying
parameters being the moisture content and the temperature. Seasonal
changes provide a fluctuation in the presence of outdoor contaminants
which by introduction into a building via infiltration or an outdoor
air intake can also alter the concentrations of bacterial and fungi
spores in a building.
Moisture
in less visible areas of a building allows contamination to multiply
until the conditions are evidenced by either an investigation or visible
evidence of fungi or bacterial. Investigations are often prompted by
health complaints of occupants.
Ozone
Ozone
is reactive gas composed of three oxygen atoms. It can be generated
by electrical discharge or ionizations and by ultraviolet radiation
interacting with diatomic oxygen molecules. In general outdoor concentrations
of ozone exceed indoor levels. Environmentally ozone can be generated
by electrical storms and oxidant pollutant processes of air pollution.
Outdoor concentrations are on the order of 0.15 parts per million whereas
indoors, ozone produced by sparking electric motor brushes, copy machines
and electrostatic air cleaning devices are generally 0.02 ppm or less.
Ozone is
an irritant that can cause cough, irritation of the eyes, nose and upper
respiratory passages and chest discomfort. Concentrations of 0.3 parts
per million will consistently cause detrimental lung function effects
in healthy exposed subjects. It had been believed that irritation and
lung dysfunction were -reversible effects that quickly return to baseline
upon cessation of exposure. Presently, there is increasing concern regarding
the generation of free radicals from ozone interaction with functional
macromolecules that can result in lipid peroxides and other oxidation
products that can impair biological systems.
Industrial
Workplace Guidelines
0.2 MG/M3 (0.1 PPM) 8 hr TLV-TWA
0.6 MG/M3 (0.3 PPM) 15 min. STEL
Radon
Radon
is a radioactive gas produced by the decay of uranium which is present
to some degree in all soils. Radon is invisible and has no smell or
taste.
Radon is
released through the soil mix and carried into buildings along with
soil gas. Soil gases may also carry other harmful substances into buildings
such as molds, moisture and methane. Radon is not a problem in office
buildings and does not give rise to acute symptoms.
Industrial
Workplace Standards
02MG/M3 (0.1 PPM) 8 hr TWA (NATICH)
Volatile
Organic Compounds (VOC's)
A
volatile organic compound is defined as: Any organic chemical compound
that contains the element carbon; excluding carbon monoxide, carbon
dioxide, carbonic acid, carbonates, metallic carbides and methane.
Some
Common VOC's
| Acetone |
Isooctane |
Mineral
Spirits |
| Butanol |
Isoporpanol |
Napthas |
| Ethanol |
Isopropyl
Acetate |
Normal
Propyl Acetate |
| Ethylene
Glycol |
Methanol |
Propanol |
| Glycol
Esters |
Methyl
Isobutyl Ketone |
Stodard
Solvent |
| Heptane |
Methyl
Ethyl Ketone |
Toluene |
| Hextane |
Methyl
Acetate |
Xylene |
Water,
Magnetic Technology & Industry - Can they function together in harmony?
For many plant engineers, water treatment
is a nightmare. The grains of hardness, corrositivity. TDS and other
specific characteristics of the water determines, initially,
how the water will need to be treated. For many years, chemical treatment,
in conjunction with support equipment, such as water softeners and deionizing
systems have been the mainstay of the water treatment industry. In more
recent years, the proliferation of alternatives have begun to present
themselves.
The government,
and environmentally concerned companies, have begun to realize that
we cannot continue to use many of the chemicals presently in use to
treat our water systems; because these very expensive chemicals are
appearing as pollution in our aquifers (drinking water). Fortunately,
most of the newer alternative systems work toward substantially reducing
or eliminating the need for chemicals.
So, lets
look at a breakthrough in one of the alternative technologies: Magnetic
water conditioning. To better understand what magnets do, and how they
do it when applied to water, we need to have a cursory understanding
of water before and after it enters the industrial environment. To the
scientist and chemist water is often thought of in its text book form,
which is pure and without any contamination intricacies. Unfortunately,
for the plant engineer, this "ideal" water does not
exist, as the water he must deal with is anything but pure. So let's
look more closely at the "real world" water we all must deal
with.
Salt softeners,
when used only for scale control in process equipment, can be eliminated
with the proper magnetic field on the input of the softener raises the
electromotive force of the solution resulting in raising the efficiency
to 99.9% whether the resin bed is old or new. As a result, regenerations
can be cut back an average of 40 to 60% resulting in huge salt savings
and while lessening maintenance costs.
Sundry
filtration systems such as de-ionizing, and reverse osmosis systems
will provide enhanced filtering capabilities once subjected to magnetic
activity. When the electrons of water molecules are charged by the magnetic
effect, the associations clustering around the suspended particles are
broken up as the molecules line up in polarization. This creates a more
solvent, fluid flow which as a higher potential which impregnates the
membrane or filter medium more efficiently. The higher impregnation
efficiency relates to a higher filtration efficiency which when coupled
with the dissolved scaling properties of the water, maintains membrane
or filter longevity free of mineral build-up thereby reducing costs
of replacement and maintenance.
Finally,
magnetic technology has grown up and can address the majority of concerns
any plant engineer has, who is looking for alternatives to the high
costs of water treatment. Boilers, cooling towers, heat exchangers,
condensers, chillers and sundry processing equipment; all of which
are part of the water system, will show enhanced manageability, improved
functionality and less down time, while using far less or no chemicals
when properly out-fitted with magnetic technology.
With the
tremendous cost of maintaining water treatment facilities, the cost
to our environment, the future of our children, and the ongoing environmental
legislation - it is very important to take a serious look at the new
magnetic treatment physics.
For more
information on magnetic technology applications, visit: www.magnetizer.com.
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