There are two separate issues buried in the question of chalk dust safety. In one sense, the main ingredients of this dust are considered to be non-toxic, which simply means they do not pose a threat when ingested. In another sense, this material can and does accumulate in the human respiratory system, which means it can create long-term health problems due to overexposure. In short, swallowing a piece of white chalkboard chalk won't kill a person, but breathing in the dust for a number of years can create or trigger respiratory problems.
Chalk dust is the natural by-product of using a chalk crayon on a blackboard. As the chalk is scraped across the rough surface of the board, particles of it are sent out into the surrounding air. Some of this dust settles to the ground or is ventilated outside, but much of it falls on clothing, furniture, electronic equipment and shelves. Teachers and students also inhale a portion as well, which usually becomes trapped in the mucus layers of the throat and upper lungs.
A small amount of inhaled dust is not considered harmful. Those with healthy respiratory systems can expel it through coughing, and the remaining material should be absorbed safely into the body. For those with chronic breathing issues such as asthma, however, exposure can trigger a reaction. In fact, many school systems strongly urge teachers to move students with respiratory problems away from the chalkboard area. Chalkboards, trays and erasers filled with dust should also be cleaned regularly.
Standard chalk for classroom use is generally made from calcium carbonate, a processed form of natural limestone. The traditional method of creating white chalk was to form a clay-like paste with the calcium carbonate and allow it to cure in chalk-shaped molds. This chalk worked well with slate chalkboards, but it also generated a significant amount of dust that floated into the surrounding air. Teachers who used traditional chalk for a number of years developed some respiratory problems, although not generally considered severe.
There is now a product called dustless chalk, designed to address the chalk dust issue. Instead of forming crayons through individual molds, the new chalk mixture is extruded into ropes, then cut to size and allowed to dry. This dustless chalk does generate a form of dust, but the particles are much heavier and tend to fall directly to the floor instead of floating in the air. Exposure to airborne particles has been reduced, but the accumulation of dust elsewhere is still problematic.
Beyond the human health aspects of chalk dust exposure, there are also potential electronic hazards. Devices such as computers and digital versatile disc (DVD) players stored inside classrooms can suffer damage from accumulated dust. As the chalk particles circulate throughout the room, cooling fans may draw them into the computers' inner workings. As it builds up on the motherboard and other heat-sensitive parts, the risk of overheating increases. This dust can also cause severe damage to sensitive electronics, such as the laser reader of a DVD player or the playback heads of a video cassette recorder (VCR).
Chalk dust is considered an irritant and an occupational hazard by a number of occupational safety organizations around the world. People who must work around it for extended periods of time may want to use a filtered mask over the mouth and nose and taking a number of breaks in a fresh air environment. They should also use other dustless methods of communication, such as dry erase boards or overhead projectors, whenever possible.
What Kind of Respiratory Diseases Are Triggered by Chalk Dust Inhalation?
Respiratory diseases like asthma could be triggered or heightened by chalk dust inhalation. Persistent cough and rhinitis are other diseases that may respond unkindly to chalk dust exposure. Silicosis can be caused by continuous exposure to silica, a chemical found in chalk.
A persistent cough can occur if there is heavier exposure. While this is more likely in other dust settings, the exposure to chalk dust is enough to put those at risk.
Though the amounts of silica in chalk dust are small, extended and repeated exposure over time can still impact the lungs and respiratory system. It is unlikely for Silicosis to form from chalk exposure because there is so little of it, but it is not impossible.
It’s important to consider alternatives to avoid this exposure for students and teachers alike, as these diseases can crop up and cause other health issues later.
How Can You Protect Electronic Devices From Chalk Dust Exposure?
Protecting electronic devices from chalk dust exposure is very similar to how you protect them from dust exposure altogether.
Keeping your computer as far away from your chalkboard as you can manage is a good start. After that, a surefire way to keep things from accumulating is to clean your surfaces regularly. If you cannot move your computer, cleaning your surfaces regularly will still be a protectant.
Using wipes or spray disinfectant to regularly wipe off the dust on those surfaces will keep it from building up and getting into those little crooks and crannies.
How Can I Keep My Chalkboard, Tray, and Eraser Chalk Dust Free?
Additionally, keeping regular maintenance with the chalkboard is also essential to keep things cleaner. For example, throwing out chalk when it reaches a shorter, harder-to-use length will keep it from breaking off and creating more dust.
Replacing your chalk erasers often will also prevent the dust from getting stuck and being deeper embedded into the material and will also ensure a cleaner service- the longer you use one, the more dust built up inside. Having a clean slate once in a while will limit the dust that is saved and kept to irritate users.
While you can always clean your erasers, knowing when to ditch them for a new one will make erasing the board easier and, at the same time, will also prevent dust accumulation.
Wiping down the board and the chalk tray regularly also keeps things clean. However, you must pay proper attention to how because blackboards can be ruined without following the correct cleaning methods.
Storage of the chalk can also make a difference; having a portable chalk basket can keep chalk easily accessible when teachers need it while keeping the chalk in one place. Having chalk sliding around the tray will increase the likelihood of dust moving around.
Taking the time to rinse out the basket every week or so will keep the chalk dust collected for easy disposal and, additionally, will keep the chalk within reach.
What Is Dustless Chalk Made Of?
Dustless chalk is still composed of calcium carbonate, like traditional chalk. During the formation process, dustless chalk is cut differently, resulting in less dust than standard chalk.
Making the switch to dustless chalk will make a noticeable difference, but it will still be necessary to upkeep maintenance. While smaller amounts of dust are released, heavier particles still linger on the floor, so it’ll become more important to vacuum or mop those classroom floors to keep things tidy.
Benefits of Replacing Chalkboards With Whiteboards
There are a few benefits to switching out a chalkboard for a whiteboard, some that you might not immediately expect. Beyond eliminating chalk dust exposure for students, staff, and computers, embracing the whiteboard encourages better classroom comprehension.
Cleaning a whiteboard is an easier process since it requires less vacuuming and dusting. There’s also less chance for dust to make its way into computers.
If replacing your chalkboard isn’t possible, a safe alternative is to keep your doors and windows open if possible while using chalk. Allowing air circulation will allow less chalk dust deposits on classroom surfaces and in the air.