The World Health Organization states that 2.4 million people die annually from various types of lung conditions that can be attributed, at least in part, to air quality. That is more than 500,000 deaths in the United States each year. The majority of these deaths come from simply breathing air, and the risk rises as the quality of air decreases. This fact is very important to those of us who make our living on construction sites; individuals in the construction trades are at a higher risk of developing an occupational lung disease, especially occupational asthma. To help clarify what this disease is and how it may affect us and our employees, here are some basic questions and answers.

What is asthma?
Asthma is caused by a narrowing of the bronchi and the smaller passageways leading to the lungs. It results in difficult, labored breathing; tightness of the chest; coughing; and abnormal breath sounds, such as wheezing.

The body’s response to inhaling specific substances in the workplace causes occupational asthma. It’s an allergic reaction to a specific substance, such as wood dust, caulks, adhesives and carpeting.

How does it develop?
Asthma, occupational or otherwise, can be triggered in a variety of ways and, frankly, is not completely understood. What is known is that there are two types:

• Allergic asthma: When the body comes in contact with a foreign substance, the natural response is to make antibodies to protect itself. Most times, this works very well, but sometimes, the antibodies respond incorrectly, causing allergies. Exposure to an industrial substance can cause this release of antibodies. As a result, the body circulates chemicals that make airways contract, restricting airflow to the lungs.
• Nonallergic asthma: Following exposure to an industrial substance, the body releases the same chemical as with allergic asthma, even though it produces no antibodies. This release also causes the air passages to narrow. The reason for the release without the presence of antibodies is unclear.

How long does it take to develop asthma?
There is no exact formula for asthma development. It can be as quick as 10 days after exposure or delayed for as long as 25 years.

What’s an attack, and what causes it?
An asthma attack usually occurs when a person breathes in a trigger substance, such as smoke or fumes. Trigger substances cause the body to release chemicals that constrict airways, meaning less air moves through the lungs. Less air leads to coughing, chest tightness, troubled breathing and wheezing.

There seems to be three patterns for the onset of an asthma attack:

• Immediate: Asthmatic symptoms begin within minutes of being exposed, and the attack reaches its peak after about 20 minutes. Full recovery from an immediate asthma attack takes about two hours.
• Late: Although there is variability, symptoms typically begin several hours after exposure and are the worst after about four to eight hours. Recovery typically occurs within 24 hours.
• Dual or combined: This is the occurrence of both immediate and late asthma types.

How can you prevent asthma attacks?
Typically, triggers vary; some of the more common ones include stress, tobacco and wood smoke, air pollution, and gas fumes. The best way to avoid an asthma attack is to stay away from triggers. For occupational asthma sufferers, this may be easier said than done. Triggers that cause an attack may be part of the job, such as physical activity and being exposed to weather conditions (e.g., thunderstorms, high humidity and cold, dry air).

Drugs can help control asthma symptoms, but avoiding exposure is best. Dust masks and respirators can help minimize workplace exposure. Remember that, in order to be most effective, masks must be correctly fitted and well maintained. Increased ventilation at the work site also can minimize the amount of trigger substance that workers come in contact with, thus helping to minimize the risk of an attack. Weather condition exposure may be harder to control; however, wearing a mask in cold weather can help to warm and moisturize the air before it enters the lungs. Work schedules also can be adjusted to avoid triggers.

When to seek medical attention
Important symptoms to look for include the following:

• Wheezing that occurs when breathing in and out
• Almost continuous coughing
• Difficult, rapid breathing
• Difficulty completing sentences
• Becoming pale and anxious
• Blue coloring of lips or fingernails

If these symptoms arise, immediately call 911 or emergency services, and try to keep the individual still and calm.

Even if you do not have asthma, knowing this information may help to save the life of a coworker.


KELLY is a safety and health specialist with Intec, a safety consulting, training and publishing firm that offers on-site assistance and produces manuals, training videos and software for contractors. She can be reached at 800.745.4818 and dkelly@intecweb.com. Joe O’Connor edited this article.