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Let’s face it. A hog building is not always the most pleasant place to work.

While unpleasant conditions may not directly affect the performance of the animals, they can have a negative impact on the work force. If steps are not taken to maintain a healthy and safe environment
inside hog units, it usually leads to lower worker productivity, more absenteeism and higher employee turnover.

If a program is not currently in place that promotes worker safety and health, now is the time to start one. If you already have a comprehensive safety program in place, now is a great time to review it. Perhaps the most important aspect of a worker health and safety program is to make employees more aware of the risks. This is especially critical for new employees who have little or no experience working with livestock or in hog buildings.

Two Types Of Air Quality Problems

Air inside and around hog buildings is often contaminated with two basic types of pollutants: gases and dust. Nearly 200 different gases have been identified in air from inside swine units. The vast majority of these gases are harmless. Others are unpleasant but present little, if any, health risk. Extended exposure to some gases is a health concern and one, hydrogen sulfide, can be lethal.

At low levels, hydrogen sulfide is an irritant that causes burning eyes, a runny nose, a “scratchy” throat and a cough. At high concentrations, however, this odorless gas causes pulmonary edema or fluid buildup in the lungs. Within seconds a person feels dizzy and nauseated. If unable to reach fresh air, they collapse and their lungs quickly fill with fluid.

Extreme caution should be used when emptying or agitating below-ground liquid manure storage. Agitate pits slowly so hydrogen sulfide can dissipate before reaching dangerous levels. Never allow employees to enter a liquid manure storage facility without a source of fresh air.

Ammonia is commonly found in hog buildings, especially in the winter when ventilation rates are low. Although not extremely dangerous, ammonia irritates the nose and eyes and makes working conditions unpleasant. Other gases that either present a health rise or produce unpleasant odors include carbon monoxide, carbon dioxide and methane.

Controlling Dust and Reducing Gases

Respiratory problems among hog farm workers are common and are often related to dust levels. Hog dust is not just a nuisance, it’s a biologically active material.

The protein content of dust found in most swine units is high enough to support bacterial
growth. Fine dust particles can carry irritants deep inside the lungs. All workers should have easy access to dust masks or an air purifying respirator and should be strongly encouraged to use them.

Washing rooms between groups helps keep dust at tolerable levels. This works well in farrowing and nursery units because the rooms are emptied every few weeks. But the finishing phase lasts much
longer — especially in wean-to-finish buildings — and there is seldom an opportunity to wash an entire gestation building. Some operations find it helpful to wash portions of buildings every few weeks to reduce dust levels, but care must be taken not to stress pigs during cold weather.

Feed particles are often the culprit in buildings with a severe dust problem. Liquid feeding dramatically cuts dust levels. Also, studies show that adding fat to rations will reduce feed dust by 50%. Allowing dry feed to freefall a few feet or even a few inches puts dust into the air. A PVC spout is an inexpensive way to prevent a cloud of feed dust when feeders are filled.

Increased air movement is another possible solution for a dust problem. Canadian research indicates over 90% of respirable dust can be removed from hog buildings through ventilation. There are tradeoffs with this approach, especially during cold weather months. Energy costs will rise and pigs will experience stress if air is exchanged in ways that create drafts at floor level.

Virtually all gases found inside hog buildings are the by-product of waste decomposition. The best way to keep gases from reaching unpleasant or dangerous levels inside units is frequent removal of manure. If the waste handling system is designed to store waste inside the building, ventilation fans are needed to draw gases from pits.

Other Considerations

Noise is a major source of stress for people who spend several hours a day inside hog buildings. Noise levels high enough to damage a person’s hearing are often measured inside confinement units, especially if the animals are restless due to an infestation of external parasites. Extended exposure to noise can cause permanent hearing loss.

Lighting is another important factor in the in-house work environment. No one wants to work in a dungeon. Plenty of florescent lighting will brighten the room and make employees more observant. Natural light should be utilized whenever possible.

This article is from the Aug. 15, 2008 issue of Elanco Animal Health's Pork Profit Edge newsletter.