Indoor air quality

Animal dander in homes is a common source of respiratory irritants associated with asthma and allergies. Animal dander, hair, and other organic debris in homes can also result in a significant increase in the level of dust mites, mite fecals, and other allergenic insect parts and fragments.
Signs of “hidden” animal presence: We often find evidence of other animals who have been frequently present in a home even though the human occupants didn’t know it – either because the animal was the pet of a prior owner (Chinchilla hair at above left) or a nocturnal visitor to the food bins (mouse hair at above right). Finding evidence of animals might mean that additional cleaning is needed to remove their remaining allergenic particles.

The U.S. EPA indicates that allergens are found months after a pet (or mouse problem) has been removed.

Our particle studies in homes with pets show that although a dog or cat who is never allowed out of the basement will concentrate its hair and dander at that level, I will find the animal dander and hair at all floors and in every room of the home.

We often find significant levels of allergens in buildings where the source animal(s) have been gone for years if professional cleaning has not been performed. Even when cleaning is thorough I can find allergen materials remaining. In fact, I find some levels of animal dander in most homes, even if the home has never housed a pet, and in homes where a previous owner had pets, the dog or cat dander is often among the most frequent particles found in our samples.

REDUCING PET ALLERGENS: How to Reduce (somewhat) Exposure to Pet Allergens

What else can you do to reduce the indoor animal dander problem in a home with asthmatics or allergics? These suggestions are roughly in order of importance and effectiveness, in the author’s opinion, with some consideration given to ease of implementation.

Frequent house cleaning including damp mopping or HEPA vacuuming will not cure this problem but will reduce the particle levels

Eliminate indoor carpeting. In buildings with wall to wall floor carpeting or large area rugs, our indoor particle studies show that these floor coverings form an inexhaustible reservoir of allergens including the original animal dander from pets which no amount of vacuuming or “carpet cleaning” will remove completely. Depending on the historic indoor moisture levels, quite often I also find that dust mite fecals, another very common indoor allergen, are at much higher levels in homes with pets. More pets or larger pets, shedding more dander and thus feeding more mites, produce higher levels of mite fecals in indoor dust.

HEPA vacuum cleaners, especially units that do not have significant air leaks when the vacuum is running, do not stir up as much airborne debris, allergens and other particles, as ordinary vacuum cleaners. But before buying an expensive vacuum cleaner, further evaluation of the leakiness, operating cost, and bag or filter changing convenience should be made. I collect data on vacuum cleaner effectiveness but this work is not ready for release. When it is I’ll post it at this website.

Central Vacuum Systems, if properly installed, vent directly outside, avoiding the issue of stirring up indoor particles during house cleaning. It’s a more-costly but great idea. Just be sure the vac is properly vented. I’ve inspected homes at which the central vacuum machine was in a laundry room or basement, venting its dust back into the home.

Humidity control: is a step more critical than may be obvious. In homes with high humidity, of which the most egregious case is a carpeted damp or wet basement, the level of dust mite and other insect fecals (including carpet beetles and other mites) skyrockets. In homes with a high level of animal dander these animal skin cells form a feast for dust mites.

When we investigate the air and dust in buildings which have a combination of a high level of animal dander, carpeting, and high humidity, these three strikes against indoor air quality are a strikeout for asthmatics and people with allergies. Keep the humidity low enough to discourage dust mites (45% to 55%, with a lower target for problem areas like basements and crawl spaces) and fix gutter/downspouts, plumbing leaks, or other sources of indoor moisture.

Good Air Purification Treatment will fully sanitize and disinfect, deodorize and eradicate smoke odors, pet dander, dust mites, bedbugs, cockroaches, bacteria, viruses and most all other allergens, VOCs and noxious odors, living or not that might be deeply embedded in carpets, furniture, mattresses, behind walls, under sinks, in cabinets and in drawers.