Safety Blog
By Ken Roy
Posted on 2024-06-20
Exposure to silica particulates is a serious potential health and safety risk to students and especially, teachers. Remember that students come and go from instructional spaces, while teachers remain in instructional spaces throughout the day. The risks of silica particulates exposure involve respiratory issues such as silicosis, a serious lung disease caused by inhaling silica dust over time. Chronic exposure to silica dust can also increase the risk of developing other respiratory conditions such as chronic obstructive pulmonary disease (COPD) and lung cancer. Additionally, silica dust can irritate the eyes, skin, and mucous membranes.
In middle and high school art, science, and technology education instructional spaces, there is a potential safety hazard and health and safety risk of silica exposure. The exposure depends on the materials and processes being used. Silica generally is found in materials such as clay, quartz, sand, and some types of stone. The potential hazard and resulting risks can happen when these materials generate airborne particulates.
The following are situations that can put teachers and students in harm’s way when they are exposed to silica particulates.
1. Art Classes. In art classes, silica exposure could potentially occur when students work with materials like clay, ceramics, or sculpture materials containing silica. Activities such as sculpting, shaping, or sanding these materials can generate silica dust, which if inhaled, can pose health risks.
2. Science Classes. In science classes, silica exposure could potentially occur when conducting experiments that involve grinding, cutting, or drilling materials containing silica. For example, experiments involving rocks, minerals, or glassware could potentially release silica particulates into the air.
3. Technology Education and Engineering Classes. In technology education and engineering classes, silica exposure could potentially occur during activities such as woodworking, metalworking, or using masonry materials. Cutting, sanding, or drilling these materials can generate silica dust.
The following safety protocols are recommended for addressing silica particulates in instructional spaces.
1. Assessment and Monitoring. Conduct regular assessments to determine the silica content in materials and monitor the levels of dust generated during various activities.
2. Engineering Controls. Ensure proper ventilation in the instructional space by using exhaust fans, opening windows, or installing ventilation systems designed to capture and remove airborne dust.
3. Work Practices. Establish safer work practices to minimize dust exposure. Encourage safer work practices such as avoiding dry sweeping or compressed air for cleanup, as these methods can generate airborne dust. Instead, use vacuum cleaners equipped with HEPA filters or wet mopping to clean up dust.
4. Personal Protective Equipment (PPE). Use appropriate PPE, including respirators with N95 or higher filtration efficiency, protective clothing, and eye protection. Ensure that PPE is properly fitted, maintained, and used according to manufacturer guidelines.
5. Training and Education. Train staff and students on the hazards of silica exposure proper handling techniques and the use of controls and PPE. Teachers and students should be aware of the potential health risks and know how to protect themselves.
6. Hygiene Practices. Encourage good hygiene practices to minimize dust exposure. These include regular hand and face washing and avoiding touching the face with dusty hands. Provide access to handwashing facilities and/or hand sanitizer.
7. Medical Surveillance. Implement a medical surveillance program to monitor the health of teachers exposed to dry clay dust and all other sources of silica particulates. Regularly monitor silica dust levels in the instructional space to ensure that exposure levels are within safer limits. You can monitor silica dust levels in the instructional space through air monitoring or by having individuals working with clay wear personal dust monitors. This may also involve regular medical examinations to detect any early signs of respiratory issues or other silica-related health problems.
8. Emergency Response Plan. Develop and communicate an emergency response plan in case of accidental exposure or release of dry silica dust sources. This plan should include procedures for evacuation, decontamination, and medical treatment, if necessary.
9. Legal Safety Standards and Better Professional Safety Practices. Ensure compliance with relevant regulations and standards related to silica exposure in the workplace. These may include regulations set by occupational health and safety agencies, such as the Occupational Safety and Health Administration (OSHA). More information can be found at OSHA’s Silica Standards page.
In addition, refer to the Consumer Notice resource titled Silica Dust at https://www.consumernotice.org/environmental/silica-dust/silicosis/.
10. Regular Review and Improvement. Continuously review and improve safety protocols based on feedback, incident investigations, and advancements in technology or knowledge regarding silica exposure hazards associated with silica particulates.
One very effective means of controlling exposure to clay dust to protect employees and students was developed by Glastonbury Public Schools in Glastonbury, Connecticut. Pursuant to a field safety inspection and evaluation of activities performed by students in their high school Ceramics class, the district’s Director of Environmental Health and Safety and their Director of Operations and Maintenance focused on the efficiency of the existing ventilation system. More specifically, the focus was on how well fine clay dust particles in the air and surfaces were being removed to protect the safety and health of occupants, namely students and teachers.
It was determined the current exhaust ventilation system needed to be redesigned to ensure the fine particles from sanding clay materials are positioned closer to the breathing zone for each student. The challenge was that multiple students worked closely on a given work table, so a system needed to be designed that draws air away from each student working with clay and creating fine dust particles. Several direct portable standalone systems were explored, but they were only designed for one user. The two directors decided to design custom fabricated linear exhaust boxes fixed atop each stainless-steel table where air would be pulled away from each student as they worked on pottery. The idea in part came from wood and/or metal dust collection systems found in technology education/engineering lab power tools to protect students and teachers from health issues.
Each table seated six students working simultaneously. The linear exhaust boxes at the table level draw particulates from the work surface, then are connected to a round exhaust ductwork that travels under each table and branches upward toward a main ceiling duct and to a new rooftop exhaust unit. With assistance of a mechanical engineer to design the volume of exhaust air needed for the main rooftop unit and duct sizing capable of handling the student capacity at each table, an effective model was developed. Since completing the project several years ago, there are no visible dust levels present at the work surface, which confirms that fine particles from sanding clay have been addressed by this innovative system. This allows for safer use of clay without fear of inhaling silica dust particulates.
Implementing these safety protocols can help protect teachers and students from potential silica safety hazards and resulting health and safety risks in school art, science, and technology education/engineering instructional spaces.
Submit questions regarding safety to Ken Roy at safersci@gmail.com. Follow Ken Roy on X.com: @drroysafersci.
Safety Blog Acknowledgement
NSTA Chief Safety Blogger Dr. Ken Roy wishes to sincerely thank Terry Turner, Senior Writer at ConsumerNotice.org (tturner@consumernotice.org) for his professional review of and contributions to this commentary.
In addition, I sincerely want to thank Albert Costa, Director of Operations and Maintenance, Glastonbury Public Schools, Connecticut (Costaa@glastonburyus.org), with whom I had the honor of working for many hours as Director of Environmental Health and Safety (Royk@glastonburyus.org) on the design development and planning for the Art Department’s silica particulate dust collection system.