Farmer's Lung and Other Reasons Why Farmers Need Respiratory Protection

Farmer's Lung and Other Reasons Why Farmers Need Respiratory Protection

by Aden Tate

The fragility of the global food supply, demonstrated by the numerous events of the past two years, has shown millions of Americans the need to be able to provide one’s own family with food even despite what is happening in the world at large.

It was because of this fragility that seed suppliers throughout the nation saw a run on supplies, novice gardeners began to explode in numbers, and more and more people began to get involved in homesteading on a nationwide scale. Alberta, Canada, saw a considerable increase in the number of people seeking information on the raising of chickens, and within the United States, sales of baby chicks multiplied.

In 2020 alone, one baby chick company saw their sales rise 400%. People don't just buy farm animals, however. They also have to build farm infrastructure. To raise chickens, pigs, sheep, rabbits, and whatever else, they must create a structure for them to live in. They also must purchase large amounts of hay, straw, and animal feed.

Farming and homesteading are fantastic activities that this author believes more people should get involved in, but there are some things that newcomers to homestead food production should know. One is the importance of proper respirator protection when working within enclosed spaces.

While Joel Salatin's methods of farming are arguably the best on the planet, the fact remains that there are a lot of people out there who build a chicken coop, stable, or barn and let things get very nasty very quickly. Eventually, when maintenance reaches a point where the new farmer can no longer stand it, they will decide to clean everything out.

Farming is not the most dangerous job on the planet, and it truly is an activity filled with a lot of joy that those not involved in it miss out on. To wake to the sound of the rooster to go out and feed the dairy goats on a still December morning when the stars are bright is incredibly peaceful. But just like the new horse owner needs to know how to stay safe around such a massive animal, the new farmer needs to learn a few basics of protecting themselves when cleaning out barns, coops, and stables.

Many people need to understand that there are a few threats out there to the farmer's respiratory tract that they need to be aware of. One of these threats comes in the form of something known as "farmer's lung."


  • 01

    Farmer’s Lung

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  • 04

    Organic Dust Toxic Syndrome

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    What Can I Do?

  • 06

    Frequently Asked Questions

Farmer’s Lung

First discovered in the 1700s among farm workers in France, Farmer's Lung isn't an infection but an allergic reaction instead. You can't catch Farmer's Lung from other people, and if you have it yourself, you don't have to worry about giving it to anyone. It's a gift you get to keep.

The chief cause of this reaction is exposure to moldy crops. Typically, this comes in the form of moldy hay or straw, but it doesn't limit itself to just those two grass forms. Corn, tobacco, soybeans, sorghum, and just about any other crop imaginable can develop mold on it that if you let yourself get exposed to large amounts of it, you could end up with a case of Farmer's Lung.


Estimates compiled over time have indicated that between 2-10% of all farmers have some form of Farmer's Lung.

Farmer's Lung has three forms: acute, sub-acute, and chronic. All three come from the same source – exposure to moldy crops.

Let's say a new chicken flock owner has been storing their straw bales underneath a tarp outside of their chicken coop. Every week, they take off the tarp and throw more straw into the nest boxes and onto the coop floor. However, despite that tarp, some level of moisture is likely going to hit those straw bales.

Six months down the road, the chicken owner finally gets around to cleaning out the coop with a pitchfork and a shovel. It takes them two hours of solid work in a small, enclosed space without respiratory protection, and they stir up a lot of dust in the process.

Acute Farmer’s Lung

Situations arise where they could come down with an acute case of Farmer's Lung. Typically, this presents itself within 4-8 hours after the initial exposure and manifests similarly to a case of influenza.

The victim will end up with a fever, chills, muscle aches, a general feeling of sickness, a dry cough, shortness of breath, difficulty breathing, a fast heart rate, and a fast respiratory rate. This Acute Farmer's Lung case typically subsides after 12 hours but can last up to 12+ weeks. It's not a fun time.


Farmer’s Lung cases are often misdiagnosed as pneumonia.

Sub-Acute Farmer’s Lung

Sub-acute is a "low-burn" type situation and is the most common form of Farmer's Lung. The signs and symptoms aren't as overt as an acute or a chronic case, but they're certainly still there.

The individual with sub-acute farmer's lung will gradually lose weight, experience body aches, feel sick, have chills, and experience shortness of breath. Things won't be as bad as an explicitly acute infection, but there will be signs and symptoms of a problem on the back burner. Unless the farmer begins to take better steps to protect themselves, they could very quickly develop a worse case of this allergy.

Chronic Farmer’s Lung

Suppose the farmer routinely exposes himself to mold year after year and doesn't use respiratory protection to protect himself. In that case, he can easily end up with a chronic case of Farmer's Lung, which results from regular acute farmer's lung episodes. If the farmer refuses to take active steps to prevent further exposure to mold at this point, their chronic case will get even worse.

Farmer's Lung is a hypersensitivity to mold, after all, and once this allergy has been established, the body reacts in much the same manner as it does with somebody allergic to bee stings. The higher the exposure, the worse things become.

Somebody with a chronic case will lose weight, experience shortness of breath, have a persistent dry cough, fatigue, feeling weak, and develop permanent lung damage. By this point, these signs and symptoms are typically lifelong conditions.

How to Keep from Getting Farmer’s Lung

The first thing that a farmer can do is to avoid moldy crops. However, ask any farmer out there, and they will tell you that this is just about impossible to avoid altogether. One study of Canadian farmers found that 20-40% had antibodies within their bloodstream for the antigens that cause Farmer's Lung. This percentage means that many people have been exposed to moldy crops.

If you can protect your crops as best as possible against developing mold, however – something that can be managed by limiting their exposure to moisture – you can do a lot to keep yourself from ever having to deal with moldiness, to begin with.

Another step that farmers can take is to deal with moldy material out in the open whenever possible. There is minimal risk to the man dealing with loose straw out in the field compared to the man breaking open musty straw bales inside his tiny chicken coop. Use open air to work whenever possible.

One step the author personally likes to take is to soak down the bedding with a garden hose before shoveling out the chicken coop or the goat house. This causes moisture to bind to the dust, keeping it from floating in the air.

Lastly, wear proper respiratory protection when cleaning out barns, stables, coops, or any other situation where you'll be dealing with potentially moldy organic material. Despite your best efforts, there will be times when you cannot avoid working with moldy materials in dusty areas as a farmer or homesteader. And that's okay, but you need to ensure that you are protecting your lungs in the process.

It's an occupational hazard. Every job has hazards. The man who works in the factory likely has to wear steel-toed boots. Kitchen workers often wear Kevlar gloves. Loading dock workers often wear back braces. Yet despite this, nobody thinks less of it. They know these are occupational hazards and do what they can to cope.

Could a jackhammer hurt your toes? (Image source: Image courtesy of Wikimedia Commons.)

It’s no different for the farmer. Wearing proper respiratory protection is one of the ways that he can keep himself safe, as he is keeping the farm as hygienic as possible.


Silica is a shiny mineral found in sand, granite, and soil, and it's the most common mineral on the earth's surface. Because of this, farmers need to be particularly careful when working in dusty conditions.

If rain hasn’t fallen for several weeks and the soil is dry and dusty, if the farmer goes out to plow, he will generate massive dust clouds. Within this dust will be trillions of tiny, crystalline pieces of silica.

When this silica is inhaled, it acts as an irritant in the lungs. Given enough time, this can result in a condition known as silicosis. While there are varying types of silicosis, they all have virtually the same signs and symptoms – difficulty breathing, a chronic cough, and potentially weight loss and fatigue.

(Image source: Image courtesy of Wikimedia Commons.)

This is typically a more prevalent disease in mining, masonry, and foundry, and it can and does impact the farmer's world as well. While it's not contagious and takes a long time to develop, once you have it, there is no treatment.

A silica cloud. (Image source: Image courtesy of Wikimedia Commons.)

The patient not only has to deal with the signs and symptoms of their condition, but they are also at an increased risk of developing cancer, bronchitis, or other illnesses such as tuberculosis.

How to Keep from Getting Silicosis

A straightforward step a farmer can take here is plowing his fields with a tractor with an enclosed cab. These enclosures typically offer air filtration, which can serve as an excellent means of decreasing the amount of silica within the air around the farmer's face.

However, when that is impossible (tractors are expensive), the farmer will want to consider using respiratory protection while plowing dusty fields.

Miner’s lung, tuberculosis, and silicosis all rolled into one. Image courtesy of Wikimedia Commons.


One of the things about those enclosed spaces where farmers keep their animals is that they WILL attract rodents. That's just the way that it is. It's a warm space away from predators, abundant food (you will never be able to keep all animal feed off the ground), and plenty of comfy nesting material (straw/hay).

Mice like farms, which is one reason barns typically are home to several barn cats. These feral felines help minimize these infestations.

Rat terriers do a fantastic job controlling these rodents as well.

However, you will never be able to eradicate 100% of the rodents around your farm.

And one of the problems with this is that rodent feces has the potential to carry something known as hantavirus. Hantavirus is an enzootic disease, meaning it's something terrible that humans can catch from animals. Typically, hantavirus will happily reside within a rat or mouse without causing them any issues. But it's an entirely different story when it makes the jump to human beings.

While there are several different types of hantavirus, there are two main conditions to be concerned with at present: hantavirus pulmonary syndrome and hemorrhagic fever with renal syndrome.

Both of these primarily seem to be caused by inhalation of aerosolized mice and rat poop. Voles can also spread the disease, but mice and rats are the major players.

Typically, people end up coming down with this infection when they have cleaned out a small, enclosed area where rodents have lived for some time. Farm structures are a perfect place for this. Thankfully, there aren't a lot of cases of this annually within the United States (only 200), as this is a disease that other parts of the world have a much more difficult time with. Still, either way, you want to avoid ending up becoming a statistic.

(Image source: Image courtesy of Hantavirus)

Even though there are only 200 cases annually in the US, the case-fatality rate is around 40-60%. Due to those significant percentages, there's not much that can be done from a medical standpoint other than to ensure that the patient is comfortable as possible while battling the infection. The same is mainly valid for the hemorrhagic version. There are no known FDA-approved medications to treat the hemorrhagic version of hantavirus, but it isn't as lethal as the pulmonary form, as it "only" has a case-fatality rate of around 12%.

With the number of chicken coops, stables, and barns throughout America, is this a statistically significant threat? Probably not. But it is still a threat that a farmer must be aware of, especially if he has noticed a heavy rodent infestation on his farm.

Organic Dust Toxic Syndrome

Also referred to as "Silo Unloader's Syndrome," this is often misdiagnosed as Farmer's Lung. The misdiagnosis makes sense as the personnel who come down with both of these conditions tend to be of the same population, and the way these two illnesses manifest is very similar.

With Organic Dust Toxic Syndrome (ODTS), however, one doesn't need to come into contact with moldy crops to get sick. Instead, all one needs to do is be exposed to large amounts of animal feed or other dusty organic material. Chest tightness, fatigue, muscle aches, chills, fever, cough, and shortness of breath are some of the signs and symptoms here. In addition, ODTS doesn't result in the severely low blood oxygen levels that Farmer's Lung can produce.

Typically, the signs and symptoms will start roughly4-8 hours after exposure, and it is not an illness that you can catch or pass to another. One study found that most (95%) of those impacted by ODTS saw their signs and symptoms decrease by the end of a week.

For the individual farmer, if you find yourself needing to clean out a silo or are dealing with massive amounts of corn (the author has noticed this is particularly dusty) or some other type of animal feed, it may be worthwhile to consider the health impact of standing in that dust cloud for extended periods.

Having to clear out grain bins or remove moldy feed has been noted as a primary cause of ODTS, but other materials such as hay, straw, and woodchips have also been found to be causative agents of ODTS. Hence, the principle remains: if you're going to be heavily involved in moving dusty materials, you need respiratory protection.

What Can I Do?

One of the best things you can do as a farmer or homesteader to protect your lungs is to ensure that you have access to quality respiratory protection when working in enclosed areas.

All of the above threats can significantly be minimized through the proper use of respiratory equipment. For most farm tasks requiring respiratory protection, you would be well-protected by wearing a MIRA Safety Tactical Air Purifying Respirator.

This respirator is a half-face design, helping to keep the farmer from overheating as he is working in enclosed quarters on a hot July day. It will allow the farmer's vision to continue as he is working in a darker environment.

When working in areas where viruses are a concern (e.g., hantavirus), proper eye protection will also be needed. Viruses like to enter the body through mucous membranes, and the eyes serve as an excellent access point for viruses. The MIRA Safety CM-6M would function perfectly in these situations.

And, of course, a gas mask is useless without a filter. We offer several filters here at MIRA Safety, but for farm purposes, one would do very well with our budget-friendly DotPro 320. These filters do a superb job of filtering out particulates in the air. They contain a P3 filter, known for filtering out 99.9999% of airborne particulates, and can even work to protect one against viruses.

Farming is not a terrifying occupation.

Farming is one of the oldest occupations there is, and millions of people around the world are involved in it still today. There's absolutely no reason to be terrified of farming, and farmers show signs of more robust health in many ways than the general population. For example, farmers have lower incident rates of asthma than the general population.

But that's not to say that farming is without risk. Risk is expected, and it's a part of living on planet earth. There will always be risks, but if we know what those risks are, we can take the steps necessary to ensure that we have minimized them as much as possible. When it comes to issues such as farmer's lung, hantavirus, or other respiratory problems on the farm, MIRA Safety has your back (and lungs) covered.

What are your thoughts on all this? Do you regularly use respiratory protection while cleaning your stables, chicken coops, or barns? Have you ever had a case of Farmer's Lung? Let us know what you think in the comment section below.


Where does Farmer’s Lung typically happen?
Can children get Farmer’s Lung?
Are only farmers at risk of Organic Dust Toxic Syndrome?