Indoor Air Quality

Indoor air quality is an important part of your home A/C and Heating system.

Indoor Air Quality

Here in Slidell, LA we are in close proximity to Lake Ponchentrain and have long hot and humid summers.

  • Disclaimer – Read the disclaimer at the bottom of the page.

Because of the geographic location of Slidell and all the allergens in the air, our home’s air may be dirtier than the air outside.

Emergency A/C repair in Slidell, LA

After talking to a lot of Slidell, LA homeowners and having them express an interest in having cleaner home air we have come up with some time tested proven solutions.

Here is an example of what some of the ducts and other HVAC components here in Slidell look like on the inside.

bad indoor air quality
Dirty Evaporator Coil

Homes in Slidell have 3 core elements in the air.

  • Dirt, Dust, and Pollen
  • Viruses, Germs, and Bacteria
  • Gases & Odors

All 3 of these Elements can have effects on our health.

  • Coughing & Wheezing
  • Runny nose
  • Sneezing
  • Asthma irritation
  • Throat irritation
  • Upper respiratory infections
  • Throat and ear infections
  • Bronchitis
  • Pneumonia
  • Depression
  • Lung health
  • Headaches
  • Effects on the memory

Here is what some of the ducts in homes in Slidell, La looks like.

Inside dirty duct means bad indoor air quality
Inside dirty duct reduce indoor air quality

Even if the ducts are clean on the inside.

Homes in Slidell, LA can still have a lot of elements in the air that come from

Below is directly from about indoor air quality

Primary Causes of Indoor Air Problems

Indoor pollution sources that release gases or particles into the air are the primary cause of indoor air quality problems. Inadequate ventilation can increase indoor pollutant levels by not bringing in enough outdoor air to dilute emissions from indoor sources and by not carrying indoor air pollutants out of the area. High temperature and humidity levels can also increase concentrations of some pollutants.

Pollutant Sources

There are many sources of indoor air pollution. These can include:

  • Fuel-burning combustion appliances
  • Tobacco products
  • Building materials and furnishings as diverse as:
    • Deteriorated asbestos-containing insulation
    • Newly installed flooring, upholstery or carpet
    • Cabinetry or furniture made of certain pressed wood products
  • Products for household cleaning and maintenance, personal care, or hobbies
  • Central heating and cooling systems and humidification devices
  • Excess moisture
  • Outdoor sources such as:
    • Radon
    • Pesticides
    • Outdoor air pollution.

The relative importance of any single source depends on how much of a given pollutant it emits and how hazardous those emissions are. In some cases, factors such as how old the source is and whether it is properly maintained are significant. For example, an improperly adjusted gas stove can emit significantly more carbon monoxide than one that is properly adjusted.

Some sources, such as building materials, furnishings and products like air fresheners, can release pollutants more or less continuously. Other sources, related to activities like smoking, cleaning, redecorating or doing hobbies release pollutants intermittently. Unvented or malfunctioning appliances or improperly used products can release higher and sometimes dangerous levels of pollutants indoors.

Pollutant concentrations can remain in the air for long periods after some activities.

Biological Pollutants’ Impact on Indoor Air Quality

On this page:


Biological contaminants include bacteria, viruses, animal dander and cat saliva, house dust, mites, cockroaches, and pollen. There are many sources of these pollutants. By controlling the relative humidity level in a home, the growth of some sources of biologicals can be minimized. A relative humidity of 30-50 percent is generally recommended for homes. Standing water, water-damaged materials or wet surfaces also serve as a breeding ground for molds, mildews, bacteria and insects. House dust mites, the source of one of the most powerful biological allergens, grow in damp, warm environments.


  • pollens, which originate from plants
  • viruses, which are transmitted by people and animals
  • mold
  • bacteria, which are carried by people, animals, and soil and plant debris
  • household pets, which are sources of saliva and animal dander (skin flakes)
  • droppings and body parts from cockroaches, rodents and other pests or insects
  • viruses and bacteria
  • The protein in urine from rats and mice is a potent allergen. When it dries, it can become airborne.
  • Contaminated central air handling systems can become breeding grounds for mold, mildew and other sources of biological contaminants and can then distribute these contaminants through the home

Many of these biological contaminants are small enough to be inhaled.

Biological contaminants are, or are produced by, living things. Biological contaminants are often found in areas that provide food and moisture or water. For example:

  • damp or wet areas such as cooling coils, humidifiers, condensate pans or unvented bathrooms can be moldy
  • draperies, bedding, carpet and other areas where dust collects may accumulate biological contaminants

Health Effects From Biological Contaminants

Some biological contaminants trigger allergic reactions, including:

  • hypersensitivity pneumonitis
  • allergic rhinitis
  • some types of asthma

Infectious illnesses, such as influenza, measles and chickenpox are transmitted through the air. Molds and mildews release disease-causing toxins. Symptoms of health problems caused by biological pollutants include:

  • sneezing
  • watery eyes
  • coughing
  • shortness of breath
  • dizziness
  • lethargy
  • fever
  • and digestive problems

Allergic reactions occur only after repeated exposure to a specific biological allergen. However, that reaction may occur immediately upon re-exposure or after multiple exposures over time. As a result, people who have noticed only mild allergic reactions, or no reactions at all, may suddenly find themselves very sensitive to particular allergens.

Some diseases, like humidifier fever, are associated with exposure to toxins from microorganisms that can grow in large building ventilation systems. However, these diseases can also be traced to microorganisms that grow in home heating and cooling systems and humidifiers.

Children, elderly people and people with breathing problems, allergies, and lung diseases are particularly susceptible to disease-causing biological agents in the indoor air.

Mold, dust mites, pet dander and pest droppings or body parts can trigger asthma. Biological contaminants, including molds and pollens can cause allergic reactions for a significant portion of the population. Tuberculosis, measles, staphylococcus infections, Legionella and influenza are known to be transmitted by air.

Reducing Exposure to Biological Contaminants

General good housekeeping, and maintenance of heating and air conditioning equipment, are very important. Adequate ventilation and good air distribution also help. The key to mold control is moisture control. If mold is a problem, clean up the mold and get rid of excess water or moisture. Maintaining the relative humidity between 30% – 60% will help control mold, dust mites and cockroaches. Employ integrated pest management to control insect and animal allergens. Cooling tower treatment procedures exist to reduce levels of Legionella and other organisms.

  • Install and use exhaust fans that are vented to the outdoors in kitchens and bathrooms and vent clothes dryers outdoors.
    These actions can eliminate much of the moisture that builds up from everyday activities. There are exhaust fans on the market that produce little noise, an important consideration for some people. Another benefit to using kitchen and bathroom exhaust fans is that they can reduce levels of organic pollutants that vaporize from hot water used in showers and dishwashers.
  • Ventilate the attic and crawl spaces to prevent moisture build-up.
    Keeping humidity levels in these areas below 50 percent can prevent water condensation on building materials.
  • If using cool mist or ultrasonic humidifiers, clean appliances according to manufacturer’s instructions and refill with fresh water daily.
    Because these humidifiers can become breeding grounds for biological contaminants, they have the potential for causing diseases such as hypersensitivity pneumonitis and humidifier fever. Evaporation trays in air conditioners, dehumidifiers and refrigerators should also be cleaned frequently.
  • Thoroughly clean and dry water-damaged carpets and building materials (within 24 hours if possible) or consider removal and replacement.
    Water-damaged carpets and building materials can harbor mold and bacteria. It is very difficult to completely rid such materials of biological contaminants.
  • Keep the house clean. House dust mites, pollens, animal dander and other allergy-causing agents can be reduced, although not eliminated, through regular cleaning.
    People who are allergic to these pollutants should use allergen-proof mattress encasements, wash bedding in hot (130° F) water and avoid room furnishings that accumulate dust, especially if they cannot be washed in hot water. Allergic individuals should also leave the house while it is being vacuumed because vacuuming can actually increase airborne levels of mite allergens and other biological contaminants. Using central vacuum systems that are vented to the outdoors or vacuums with high efficiency filters may also be of help.
  • Take steps to minimize biological pollutants in basements.
    Clean and disinfect the basement floor drain regularly. Do not finish a basement below ground level unless all water leaks are patched and outdoor ventilation and adequate heat to prevent condensation are provided. Operate a dehumidifier in the basement if needed to keep relative humidity levels between 30 – 50 percent.

End of information about indoor primary causes of indoor air quality.

Many of the people I talk to in Slidell about indoor air quality have no idea that the indoor air can be as unhealthy as it is.

I usually hear stories about various negative health effects they are having and wanting to know what they can do to have cleaner, healthier air in their homes.

Indoor air quality filter
Filter helps with indoor air quality

Most people understand that a low-quality filter with a low MERV rating won’t do much to prevent small airborne elements from circulating through your HVAC system.

MERV stands for Minimum Efficiency Rating Value. This is an industry-standard rating system that allows you to compare filters made by different manufacturers.

A MERV rating is a numerical value ranging from 1 (lowest efficiency) to 20 (highest efficiency) and tells the consumer how well the filter captures and holds dirt and dust of a specified size range. The chart below shows the MERV ratings, corresponding particle size ranges, and efficiency level as measured by the percentage of particles captured.

Slidell la superior ac and heating services

But keep in mind if you put a restrictive filter in – and the system wasn’t designed for it you can run into airflow problems.


* WARNING! This post and information on this website are for trained and certified technicians only. It is for educational purposes only. Under no circumstances should anyone who is not qualified or have the required permits or licensing attempt to use any information in this post to try and repair an HVAC or electrical system on their own. The opinions and methods I use are my opinions and I give no guarantee of any type of outcome. In other words, if you are not a trained and certified technician you should not attempt any repairs on your own. You should hire a licensed professional to do the work.  

*Income & Affiliate Disclaimer. If you purchase a product or service from one of the links on this page you should assume I earn an affiliate commission. Meaning I earn money because you purchase through one of my links. You should also assume that by clicking on my links you may receive email communications from me. 

The best advice I can give someone wanting to have a home filtration and air purification system installed is to talk to a professional and have them determine if your system and the existing ducts can handle the reduction in airflow.

error: Content is protected !!