Dust Management in Horse Facilities

slip into the bloodstream and lead to problems elsewhere in the body. While these size classifications are based upon the ability of particles to reach each portion of the human airway we apply these conventions to evaluation of equine environs.
Combinations of total inhalable thoracic and respirable dust are most often measured when studying horse facilities. Examples of contributors to increased dust levels are hay bedding and unnecessary clutter that collects dust. Mold spores can accumulate in hay grain and old tack and equipment left lying around the barn. Even the best quality hay contributes to mold and dust levels. Additionally secretions containing bacteria and viral particles originating from a sick horse can contaminate tack and equipment in the barn and often be transferred from horse to horse by shared common items and tools such as feed buckets halters and brushes.
In addition to dust horses are frequently exposed to airborne ammonia. How can ammonia be identified? Ammonia monitors and tests are available to determine levels in a particular stall or area of the barn but most horse owners recognize ammonia by smell. Horse farms have a classic odour a mixture of manure hay and grain but ammonia has a distinct smell. When cleaning a horse stall it is common to strip wet bedding down to the floor. Often there will be a noticeable difference in the smell and the odour can sting nostrils and make the eyes watery. Ammonia originating from decomposed urine in bedding can be an irritant to the respiratory tract and levels of ammonia typically increase closer to the floor of the stable. Horses that are lying down and ponies and foals whose breathing zone is closer to the ground can have significantly higher exposures to ammonia.
Mechanics of Altering Stable Air
There are several factors to consider when thinking about the overall topic of stable air quality. Both ventilation and air exchange rate in a stable greatly affect the ability of airborne particulates to settle or be removed from the barn. Ventilation is the process of replacing stale air with fresh air. Most horse barns have inadequate ventilation which can increase the risk of respiratory disease in animals and humans. The three types of ventilation are infiltration mechanical and natural. The air exchange rate how fast outside air can replace indoor air also is important. As fresh air from the outside enters a barn particle concentration in the air