By Ken Roy
Posted on 2023-03-24
Allergy and asthma cases have been increasing dramatically over the past few years. Currently in the United States, about 5.1 million children younger than age 18 have asthma. (Centers for Disease Control [CDC] and Prevention 2020. 2019 National Health Interview Survey Data. U.S. Department of Health and Human Services. https://www.cdc.gov/asthma/nhis/2019/data.htm). In 2002, 187 children aged 0–17 years died from asthma, or 0.3 deaths per 100,000 children, compared to 1.9 deaths per 100,000 adults aged 18 and older. (https://www.cdc.gov/nchs/data/hestat/asthma/asthma.htm#:~:text=In%202002%2C%20187%20children%20aged,and%20160%25%20higher%20than%20Hispanics)
Additional statistics related to respiratory issues for children younger than age 18 include the following from the CDC:
The varieties of allergens include dust, pollen, ragweed, peanuts, chemicals (e.g., pyrethrum, gelatin, glues, gums, diazomethane, toluene), latex, and more. Schools—and specifically science and technology education/engineering laboratories—have contributed to air quality and health-related allergy problems over the past few decades. Safety Data Sheets can be helpful because they list allergy symptoms from exposure to hazardous chemicals.
Knowledge/awareness of allergen sources in middle and high school science, technology education/engineering, and STEM laboratories can help with efforts to improve indoor air quality and reduce allergen levels for both students and teachers.
Laboratories tend to have potential biological (pollen, mold spores, animal dander, etc.), chemical (toxic fumes/vapors), and physical (wood and metal dust particulate) air quality hazards. Given these potential hazards and resulting health risks, inadequate or lack of air exchange in school laboratories is unacceptable and illegal. Fire and building code standards require air in laboratories to be at a 100% fresh air intake level per National Fire Protection Association (NFPA) 45. The instructional laboratory space should have mechanically generated supply air and exhaust air. All lab rooms should use 100% outside air and exhaust to the outside. No fume hood and laboratory exhaust should return into the building.
Some laboratories rely on fume hood exhaust to clear the air. Again, this in almost all cases is not acceptable. Most fume hoods are designed to evacuate only a very small area. With windows that are designed not to open, airtight buildings, and improper laboratory ventilation, airborne allergens tend to be stuck inside. This only exacerbates allergy symptoms for occupants.
Chapter 8 of NFPA 45 prescribes requirements for laboratory ventilating systems and hood requirements. The chapter applies to supply air systems, laboratory exhaust systems, lab hood exhaust, and chemical fume hood exhaust. According to the standard, all laboratory ventilation systems should be designed to ensure that fire hazards and risks are minimized. Under normal operating conditions, all lab hoods in which chemicals are present should be continuously ventilated.
Other legal safety standards and better professional safety practices for room air changes per hour in laboratories are available from the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), Occupational Safety and Health Administration (OSHA), and other sources. Ask the principal or district safety officer to have a heating, ventilation, and air conditioning (HVAC) survey done in the science laboratory to determine room air exchange rate, percentage of fresh make-up air, and other conditions.
Animals are an excellent resource for fostering learning experiences in science and agri-science laboratories. However, they also are sources of dander, feces, and urine. Some students are allergic to animal fur/hair and excretions. Ammonia products in animal urine can cause problems. Rhinitis and sinusitis infections can easily develop as a result to exposure to animals. The cedar shavings used for bedding in cages can also be a source of allergens.
Keep cages clean each day and behind glass or plastic panels, if possible. If you teach students with animal allergies, other animals such as invertebrates might be a better choice.
Bleaches, cleansers, floor treatments, spray cleaners, and soaps used by custodial services in laboratories are enough to put students into the allergy orbit if improperly applied. Pesticides are another area of concern. Many states have legislated pesticide statutes to reduce or eliminate student exposure. Use of hazardous chemicals in laboratory experiments can also cause airborne hazard problems such as vapors from acids, bases, aldehydes, and other organic substances.
Schools should use environmentally friendly or “green” chemical cleaners to reduce student and faculty exposure to allergens. Teachers should try to find alternatives to hazardous chemicals and/or introduce microchemistry.
Finally, chalkboard dust in most schools is now history. However, switching to whiteboards requires the use of low or no Volatile Organic Compound (VOC) markers.
Food items are often used in science laboratories, especially in life science and biology classes. Activities using peanuts are a popular laboratory. Unfortunately, some students are not only allergic to eating peanuts, but also to peanut vapors. Honey is another food item used at times in lab work. Some students are allergic to the pollen granules found in honey. Eggs are yet another food item used in science laboratory activities that could cause problems. Some students can be allergic to eggs. Under no circumstances should food or drink be allowed in laboratories.
Occupational health and safety regulations require good housekeeping in the laboratory. This includes keeping the area free of dust. Dust resulting from dead skin, hair particles, and other particulate matter contribute to allergen buildups.
Surprisingly, some laboratories are carpeted, harboring allergens in the laboratory. Dust mites can present their own allergy reactions and also should be addressed. Efforts should be made to remove carpeting from laboratories.
Floors in science laboratories need to be cleaned each day by the custodial staff. This will help to minimize the dust and other allergens present in the laboratory.
Dark, moist, and warm environments foster the growth of molds. Often a wet ceiling tile, a dripping pipe under sinks, wet window sills, leaks between walls, and other similar conditions will be the “Fertile Crescent” for mold growth. Once mold takes hold and spores develop, they are airborne. At the first evidence or symptoms of mold growth, contact the administration or supervisor and ask to have it abated before the allergens take over. Also, remember to never develop a compost pile inside the school laboratory or classroom. Again, this is an invitation to mold and bacterial growth on rotting organic matter, which can be a hotbed for allergens.
In summary, several proactive strategies or actions can be adopted:
1. Schools need to have registration procedures that require parents or guardians of students to inform school authorities if their child has any life-threatening medical conditions, including allergies, respiratory issues, etc.
2. The school’s medical support personnel should be required to confer with laboratory teachers about any of these medical conditions. If a student has a life-threatening allergy, parents should provide written medical advice from the child's physician.
3. Reasonable student accommodation for a life-threatening allergy should include the following guidelines:
a) An awareness/response plan should be developed involving the laboratory teacher, the school nurse, the parent(s), and the administration.
b) Preventative actions might include these:
c) Parents should instruct their child to do the following:
6. Procedures in response to an emergency
Teachers need to make sure they have information about student allergies. This usually can be secured from the school nurse or health provider. It is also prudent practice to have students complete an information form asking about allergies. It is especially important to have this information prior to laboratory work or field trips.
There also can be liability issues for teachers if a serious allergic reaction is effected by work in the laboratory or field. Be smart and be prepared: Know what you are dealing with ahead of time!
Submit questions regarding safety to Ken Roy at email@example.com. Follow Ken Roy on Twitter: @drroysafersci.
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