With science and STEM lab classes having returned to on-site school instruction this academic year—after more than a year, in some cases, of having virtual instruction resulting from the COVID pandemic—ongoing attention needs to be given to a variety of potential lab safety hazards and resulting risks. Administrators and supervisors, along with teachers, need to be aware of areas for potential safety concerns in typical middle and high school science laboratories. This knowledge will help them make sound fiscal, instructional, personnel, and safety policy decisions on what safety actions need to be taken.

The purpose of this commentary is to simply expose those potential safety issues I call the “dirty safety dozen.” I will include what science educators can do to protect themselves and others for a safer laboratory teaching/learning environment and how to do it. This information will help science and STEM educators educate and work with administrators.  Administrators can then be advocates for change, leading to improvements in the science/STEM laboratories.  

1. Air quality, including ventilation, fume hoods, bioaerosols, radon gas, etc. With the ongoing COVID issues—in addition to the usual lab air quality issues such as vapors, fumes, particulate, etc —it is critical that lab ventilation systems are working as designed with clean filters, maximum ventilation rates, ongoing room exchanges, etc. Laboratory fume hoods and/or spray booths should have been inspected per the National Fire Protection Association (NFPA) 45 standard during the summer. See more on this issue at the following Environmental Protection Agency (EPA) website: Creating Healthy Indoor Air Quality in Schools. In addition, has the lab been tested for radon by a certified commercial lab testing firm? Check out the EPA’s website Radon in Schools.

2. Water quality, including lead, copper, nitrates, and methane gas, in sinks, eyewash/shower units, etc. When was the last time water faucets in the lab were tested for lead, copper, nitrates, volatile organic compounds (VOCs), etc.? This is especially important because some lab water supplies have not been used for more than a year. Water should be tested for quality several times a year and flushed weekly. Check out the article “Eye Wash Station Maintenance” for more extensive information on the care of emergency eyewash stations and showers.

3. Electricity, including ground fault interrupters, electric and magnetic fields (EMFs), etc. When is the last time that the lab’s ground fault circuit interrupters (GFCIs) were tested to make sure they are operating correctly?GFCIs save lives by preventing shock/electrocution. Over time, they can corrode and not operate as designed. Check out additional care and operation of GFCIs in the article “Ground Fault Circuit Interrupters (GFCIs)”.

4. Heavy Metals, including thermometers, florescent bulbs, mercury, etc. Yes, mercury thermometers are still found in many labs, hidden away in drawers, in addition to mercury barometers. Broken florescent bulbs also may contain mercury vapor. Remember that mercury from old broken thermometers is the gift that keep on giving: It is an ongoing cycle of evaporation and condensing, exposing teachers and students to health hazards. Labs need to be tested for mercury and cleaned, if found to be present. Learn more from the article “Mercury in Your School”.

5. Asbestos, including floor/ceiling tiles, burners, laboratory table tops, walls, etc. Save the troops, save the children: That was the battle cry for installing asbestos on military ships and school classrooms to help prevent fires. That all ended in the 1970’s, when airborne asbestos particles were discovered to be a major health hazard. Again, labs in schools built during or before the 1970’s should be inspected and tested for asbestos. In addition, remember that older asbestos wire gauze squares also may contain asbestos and should be properly disposed of. For additional information, see the EPA’s Asbestos and School Buildings website.

6. Hazardous Chemicals, including storeroom, storage cabinets, desk  drawers, cabinets, and other unacceptable sites, etc. When was the last annual hazardous chemical waste cleanout? Is your chemical inventory up to date? As some chemicals age, they can become unstable and a major hazard. For more information, read the NSTA Safety Blog post from May 2020, Harboring Hazardous Chemicals and Disposing of Them.

7. Personal Protective Equipment (PPE), including such items as goggles and non-latex gloves. Do all of your eye protection devices, such as indirectly vented chemical splash goggles and/or safety glasses with side shields, meet the ANSI/ISEA Z87.1 D3 Standard? Do you have a means of sanitizing your visual PPE? Check out the NSTA safety paper Eye Protection and Safer Practices FAQ.

8. Walls, including lead paint, polychlorinated biphenyls (PCBs), etc. Old labs may still have lead paint, which probably is peeling off at this point and exposing both students and their teachers to lead particulate, a potential major health hazard. Get it tested! In addition, windows, radiators, and other locations in the lab may still have PCBs, another major potential health hazard. Learn more about the health issues in schools with PCBs by reading the article “Polychlorinated Biphenyls (PCBs) in Building Materials”.

Also see what one state does to address this issue: Lead-Based Paint in Schools: Maintenance and Renovation Work. 

9. Radiation, including ionizing (radioactive materials), nonionizing (ultraviolet [UV], lasers), etc. Always make sure appropriate safety signage is placed at entrance doors to labs doing activities involving lasers. Also be certain to use appropriate safety protocols to avoid reflection of laser beams in unwanted areas. Some states do not allow use of laser pointers by students in elementary or middle schools. Be careful not to house old radioactive samples that have been hidden away and forgotten. Also use caution in rock collections: You may have a radioactive specimen in your collection. Visit the website Lasers. Also check out information from the EPA, Radioactive Material in Science Classrooms.

10. Biohazards, including microbes, mold spores, bloodborne pathogens, and others. Bacteria should not be cultured in K–12 labs, except in Advanced Placement coursework. Refer to the NSTA Safety Advisory Board's safety paper Tips for the Safer Handling of Microorganisms in the Science Laboratory.

Recycling of garbage should not be done in the classroom given the potential growth of mold, mildews, and bacteria.

Never do blood typing or cheek cell labs, given the risk of bloodborne pathogen exposure.

Finally, dissections done with preservatives may expose students and their teacher to hazardous fumes and liquids. Again, make sure there is appropriate ventilation if this activity is planned. Check out the National Science Education Leadership Association (NSELA) safety papers, including this one: Experiments/Activities With Human Blood and Other Potentially Infectious Materials (OPIMs).

11. External factors, including roofing materials, oil base paints, custodial chemical technology use, custodial mechanical technology use, such as propane buffers, etc. Contractor work such as roofing, painting, and so on should only be done on off-school hours or days. The same is true with custodial facilities cleaning involving hazardous chemicals, potentially dangerous equipment, etc. There may be too high a risk of air contamination, potential fires/explosions, etc. in the lab resulting from fumes, particulate, etc. from these types of operations.

12. Personnel, factors including unsafe practices, unskilled employees, insufficient knowledge, and so on. Employers are required either by legal safety standards (Occupational Safety and Health Administration; OSHA) or better professional safety practices (NSTA) to have a chemical hygiene plan, chemical hygiene officer(s), annual safety training, appropriate PPE, lab engineering controls, and more for a safer teaching/learning experience. If these things are not in place and it creates potential hazards and resulting risks, don’t do the lab activity. If someone gets hurt and you know, for example, that PPE was required and you didn’t have it, you are legally liable under duty or standard of care. Make sure you contact the administration regarding these deficiencies and have them addressed before starting or continuing hands-on or demo lab work. For more information, see NSTA’s safety position statement, Safety and School Science Instruction.

Remember that with any one of the “Dirty Dozen,” the students come and go each day in the lab, but the teacher stays! Over time, your health can be at risk. Don’t become a statistic! And protect the health of your students as if they were your own children.

Submit questions regarding safety to Ken Roy at safersci@gmail.com. Follow Ken Roy on Twitter: @drroysafersci.