GENERAL
buildings usually protect their occupants from pollution prevailing in the city. But in many cases, during the lifetime of the building, pollution levels can be exceeded due to poor internal dirt, dust, humidity, toxic gases, mold and standing water, or create entirely new tables pollution in the interior of the building .
When over 20% of users of a building , has headaches, nausea, dizziness, sore throat, itching or dryness of the skin, nasal congestion or irritation, watery eyes, excessive fatigue and these symptoms disappear if these people leave their place of work or during weekends, it is likely that these symptoms are being caused by some contaminants in the building. The simultaneous existence of some of these symptoms in a group of people known as the "Sick Building Syndrome (SBS) or" Sick Building Syndrome "(SBS). A building under these conditions may aggravate bronchial diseases or skin.
COMMON CONDITIONS IN THE CENTRAL AIR SYSTEMS
High outside temperatures of summer.
The temperature difference between day and night is about 6 to 8 C, which favors continuing high internal humidity and heat, affecting further growth of contaminating microbial population (fungi, bacteria, viruses, etc.).
air duct insulation.
In many installations it is customary to isolate inside air conditioning ducts or heating to take advantage of the insulation and noise suppressor or silencer. This allows that there are huge wet surfaces susceptible and can become great incubators of biological contaminants called bioaerosols, as it is of biological agents that remain in the air that include fungi, spores, pollen, insects, insects and their droppings , bacteria and viruses.
size and type of systems.
Buildings that sustain this type of problems are usually very large, which is associated with the number of teams, huge pipeline routes, high amounts of condensation in more places, creates other factors that contribute to magnify the problem of pollution .
TREATMENTS POSSIBLE CONTAMINATION
Below are the most common actions from the point of view of treatment of pollutants:
1. Elimination of contaminant removal or elimination of their food resources and production (smoking ban, removing asbestos panels, etc.)..
2. Replacement. Deliberate use of less hazardous materials.
3. Isolation. Encapsulated, shielded, coated, withdrawal or other forms of separate contaminants from contact with people or the environment.
4. By design. New buildings, improve all aspects mentioned in 1 and 2. Best selection of materials, maintenance methods and their spaces, the processes of aeration and others.
5. Dust suppression and cleaning of all precincts of the building. Care and maintenance of cleaning equipment.
6. Good operating practices and maintenance of electromechanical equipment and special air conditioning systems or hot air heating.
7. Education and training of staff and the public. Knowledge of contaminants.
8. Storage and disposal. Appropriate to the toxicity of polluting materials (handling of filters).
9. Filtration and purification. Appropriate equipment, good selected and well maintained, to filter or oxidize pollutants (ozone added.)
10. Ventilation. Control of pollutants by dilution.
Other ways to remove pollutants is by absorption with other materials (charcoal filters) or "digest" them for some plants such as philodendron, spider plants and other significantly reduce the level of formaldehyde, gerbera and chrysanthemum reduce the level of benzene. The leaves and the floor area near the roots also act as purifiers. There are many indoor plants known for their air purification purposes.
most common source of CONTAMINATION.
A) In the group of particles are:
1. Respirable particles, as a group (of a size of 10 microns or less.)
2. Snuff smoke (mixed drops of liquids, solids and gases and many different).
3. Asbestos fibers
4. Allergens (pollen, fungal spores, insect parts and droppings).
5. Pathogens (viruses and bacteria), often contained in or mixed with other particles. Bioaerosols are a group that includes allergens and pathogens.
bioaerosols (Allergens and Pathogens). The
bioaerosols
or agents organic content in atmospheric air include yeasts and molds, spores, pollen, insect parts and droppings, bacteria and viruses.
The microorganisms that cause mumps or pests children, colds and flu are not considered bioaerosols.
most common sources: Sources of biological growth, mats or wet insulation boards, mats or carpets, false ceiling plates, papers and wall coverings, the furniture, the standing water in air conditioners, the cooling towers, humidifiers, de humidifiers, condensate trays and other recipients. People, pets, plants and insects can serve as carriers of biological agents into buildings, or serve as potential sources of the same.
Symptoms and health effects: The most common symptoms include sneezing, watery eyes, coughing, shortness of breath, dizziness, weakness, fever and digestive problems.
Treatment: Avoid the use of insulation in contact with air. Good design of drainage systems condensation products. Thorough cleaning and permanent carpeting, wall coverings, curtains and furniture. In this regard, it is noted that 90% of dirt on ceilings, around grills or diffusers, comes from within and no spaces outside or equipment. Delete
through proper design, the untreated air intake - induction or natural draft - buildings. Do not put vents near wet equipment and filter pollutants, filters and systems, where the problem comes from outside.
Use of Ozone: It is in this section where the most influential conveniently ozonated air injection; still very important problems of chemical contamination or physical, the most common are harmful bacterial contamination or microbiological could say. Ozone, because of its high bactericidal and fungicidal, is ideal to combat not only organic odors and "dead air", typical of any plant but also from microbiological contamination.
Among a large number of bacteria present, the most dangerous, yet common in central air systems in both cooling and heating are
Legionella pneumophilia
PSEUDOMONAS AERUGINOSA
Staphylococcus aureus
The first of these causes a great number of epidemics, many of them with deaths of people, are well-known cases: the BBC in London in May 1985, three deaths. Benidorm (Spain) 1987, a seaside hotel, dead. Private Military in Zaragoza (Spain) in 1986, two dead. The most famous case, the first led to the characterization of this whole family at the meeting of the Legion of Honor from the U.S., with a high number of deaths.
Symptoms are the same as pneumonia, so at first it was known as "atypical pneumonia": sneezing, coughing, high fever, fatigue, headache, etc.
The second "family" as well as other pathogenic bacteria that are present in any air conditioning duct is a risk factor only for the staff present, since the chances of surviving outside the human body are very small.
Just a suitably ozonated air injection ensures the absence of families and other referenced above.
In studies conducted by Petroleos Mexicanos in its air conditioning systems platform has been found and established the following bacteria and fungi:
clinical types of infection in man
1. STAPHYLOCOCCUS AUREUS
- SEPTICEMIA
- ENDOCARDITIS
- MENINGITIS
- OSTEOMYELITIS
- PNEUMONIA
2. PSEUDOMONAS
-
LUNG INFECTION - URINARY TRACT INFECTIONS IN
-
eye infections - infections, digestive
3. COLIFORM
- EPIDEMIC DIARRHEA IN CHILDREN
- Cystitis, pyelitis, pyelonephritis
INFECTIONS Gallbladder and liver
4. ASPERGILLUS
- HEARD AND LUNG INFECTIONS
The said company is renovating all of their air conditioning systems by injecting properly ozonated air, having removed all the contamination mentioned above.
Furthermore, in this case, also deleted was a high percentage of carbon monoxide (CO), very toxic, making carbon dioxide (CO2) that is not harmful to health.
environmental conditions.
Environmental conditions such as temperature and light can interact with pollutants and accentuate its effects diminish or enhance them.
temperature and relative humidity have a major impact on the outgassing of formaldehyde into the environment. The humid air encourages mold growth.
The inability of all people to control temperature, humidity, lighting level of their job has been indicated as a psychological factor of influence. The application of concepts to design ergonomic workspaces eliminates poor physical condition and improve the individual's perception of the environment of the building
Dealing with the Problem of Sick Building.
Today it is impossible to say that the problems of buildings patients, as noted in the above, come from a single source, air conditioning, as most managers believe building maintenance. This is a multidisciplinary problem that involves aspects of design, construction and, for a given building, mainly cleaning and maintenance.
airtight buildings: (curtain wall and others), building materials, air quality in the city, the conditions of electro-mechanical systems design and especially the ventilation system - which often does not exist - the quality of construction, heating type, location and management of parking and many other factors involved in the general picture of symptoms of a sick building.
Most times, when faced with a case like this, seek advice from specialists agree, especially when there is evidence (substantiated cases of allergy, a disease similar to multiple employees or other events) more or less certain that there problem.
In all cases, management should be open to diagnose the problem, active, professional. Should be sought as much information, talk to those affected, develop hypotheses to explain the problem to solve. Should not be afraid to speak clearly to those affected, and even incorporate them into the search identifying solutions and complete the necessary checks to ensure that the plan is determined to verify the internal pollution is taking the proper fruits. There are a number of formats useful in this regard, published by the EPA (Enviro mental Protection Agency) United States, which are public.
also worry about air quality, which is one of the most influential factors in the problem of "sick building" is a good deal because any increase in productivity of the workforce, pay more than the investment.
most important thing to solve or avoid these problems, and I recognized a few years ago, is the use of injection conveniently ozonated air ducts in central air, but you must select a manufacturer who has established a computing system, well experienced in order to solve this type of installation always staying below the limits of permissible ozone concentrations for different existing laws in different countries.
in Zaragoza (Spain) 19 April 2010 Roberto A.
García Gracia
Industrial Engineer in Environmental Engineering Master
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