While volcanic eruptions are rare, the impact can be severe not just on everything it touches, but on the people living near the volcano. Depending on the type of volcano, and the force of the eruption, a variety of hazards may be present. These hazards can include mudflows and flash floods, landslides and rockfalls, earthquakes, lava flow, falling ash, and the creation of ‘laze’ (lava and haze), which is poisonous and burns on contact. Volcanoes can also release potentially harmful gases such as sulfur dioxide, like what has been seen at Hawaii’s Kilauea volcano or Mount Etna in Italy.
According to the United States Centers for Disease Control and Prevention (CDC) the most common cause of death from a volcanic eruption is suffocation. So, first and foremost, adhere to recommended evacuations and area avoidance — this point is very important.
In addition to water vapor, the type of gases that may be released include acid gases such as carbon dioxide, sulfur dioxide, hydrogen chloride, hydrogen fluoride, and hydrogen sulfide. Even though the gases emitted from the volcano dissipate quickly into the atmosphere, people located close to the volcano or in low-lying areas may be exposed to levels that could be hazardous to their health. This is another reason why it is so important to follow the recommended evacuations and area avoidance.
Usually, the most visible evidence of a major eruption is the plume of ash released high into the atmosphere. This ashfall can travel long distances from the site of the eruption often causing health and safety issues along the way as it settles back to the ground. Ash is pulverized rock, ranging in color from light grey to black, and can vary in size from gritty, abrasive, sometimes corrosive particles to a fine powder.
Health Effects
Exposure to volcanic ash can cause irritation to the eyes as well as the respiratory system. When you breathe in air contaminated with ash the particles irritate the airways, causing them to contract more frequently. For people with existing respiratory conditions such as asthma, emphysema or other chronic lung conditions, exposure to ash may pose serious health risks.
Exposure to fine ash particles may also cause the lining of the airways to secrete more mucous causing people to cough and breathe more heavily. People with asthma may experience a tightening of the chest, wheezing, and coughing.
You should review information regarding the impact of volcanic ashfall as well as crystalline silica, which is also a hazardous substance that can be produced by lava domes.
Protecting Yourself and Personal Protective Equipment (PPE) Recommendations
The CDC and the International Volcanic Health Hazard Network (IVHHN) have both published guidance documents that provide information to help protect against the harmful effects from falling volcanic ash.
Some of the guidance advises:
- Stay inside, if possible, with windows and doors closed to avoid unnecessary exposures.
- Wear long-sleeved shirts and long pants.
- Use goggles to protect your eyes. If ash is continually falling, you may not be able to shelter indoors for more than a couple hours, because the weight of the ash could collapse the roof of your building and block air intakes into the building. Listen to authorities for advice on leaving the area and evacuating when ashfall lasts more than a few hours.
- Contact lenses should be avoided to prevent eye irritation and corneal scratches.
- Use a particulate filter on a half or full facepiece respirator or a disposable particulate respirator to help protect yourself while you are outdoors or while you are cleaning up ash that has gotten indoors. The particulate respirator or filter should be approved by the National Institute for Occupational Safety & Health (NIOSH).
Important Note About Choosing Respiratory Protection When Gases are Present
A NIOSH-approved particulate filter or respirator is capable of filtering volcanic ash, which is a particulate. However, some people may also find the odors released during an eruption undesirable. In that case, choosing an appropriate respirator and filter for the ash that also incorporates acid gas relief for the odors may be preferred.
The acid gases present from a volcano can include sulfur dioxide and hydrogen sulfide. A reusable respirator with nuisance level gas filters may help provide relief from the odors of these gases. However, the concentrations of volcanic gases increase with close proximity to a volcanic eruption and this increase could be too high for the respirator’s ability to filter. Respirators with filters and cartridges may not provide adequate safety if the gases exceed the levels the respirator can protect against.
Certain gases, such as carbon dioxide, are not removed by industrial or commercial respirators. Thus, it is very important to follow the guidance of local authorities and to try to avoid exposures to volcanic ash and gas. The United States Geological Survey has an informative fact sheet on volcanic gases.
It is also important to note that particulate only disposable respirators—are not effective for protection against sulfur dioxide and other gases. Certain filtering facepieces have carbon that helps reduce odors, but you still may be exposing yourself to hazardous levels that could impact your health.
Reusable respirators can help reduce exposures to gases and particles when they are used properly. This means that the User Instructions must be read and followed carefully. You should also thoroughly review these directions before donning your respirator. Men must shave every day that they use any respirator that seals to their face. Nothing must come between the edge of the respirator and the face where the seal is, including hair, scarves, jewelry and/or glasses.
Cleanup or emergency workers may need a different type of breathing protection based on their work activity and exposure time. These workers should keep in mind that disposable particulate respirators do not filter toxic gases and vapors, including sulfur dioxide.
People with pre-existing medical conditions should check with their physician to ensure that they are healthy enough to wear a respirator.
To learn more about what types of respiratory protection may fit your needs, please carefully review our Technical Bulletin: Information Regarding the Respiratory Protection Equipment and the Volcanic Eruption in Hawaii, May 2018.
Cleaning Up Volcanic Ash
In addition to the respiratory considerations, the following precautions should be taken when attempting to clean up volcanic ash during or after an eruption:
- Dry sweeping can produce high levels of ash in the air and should be avoided. Consider lightly wetting ash before shoveling or sweeping outside. Never soak the ash with water as it will cake into a heavy, solid mass which is harder to clean up and may overload structures such as a roof. For inside surfaces, consider wiping with a damp cloth.
- Fine ash particles may make surfaces slippery so use caution to avoid slips and falls, especially when removing ash from a rooftop. Fall protection is highly recommended for licensed professionals while homeowners should only attempt ash removal with a roof rake from ground level.
- Wearing a light duty protective coverall apparel while cleaning up ash outside can help prevent ash traveling indoors on clothing.
- Avoid driving in heavy ash fall. If you do have to drive, keep the car windows up and do not operate the air conditioning system.
For further information concerning the use of personal protective equipment, please bookmark our technical bulletin and do not hesitate to contact our technical specialists today at 1-800-243-4630.