Careful planning creates safe science laboratories
What should be the maximum number of students in a science classroom or laboratory? How much space should be allowed for each student? How does
a science teacher design a science learning facility that will be a safe and efficient learning environment? These frequently asked questions demonstrate that science teachers are concerned and conscientious when it comes to safety in their classrooms and laboratories. Due to the basic nature of science, science classrooms and laboratories are among the most hazardous instructional areas in the school environment, so safety for those who will be using the facilities should be a prominent concern for facility planners. The planning team should give specific attention not only to the design of the facilities but also to the establishment of emergency procedures.
Potential for Litigation
The link between science facilities and the legal arena has a long and unfortunate history. In one Texas science classroom, students were working quietly when one student bumped the elbow of an adjacent student who was holding a compass, and the point penetrated the student’s eyelid. The accident happened because students simply did not have sufficient “elbow room” to work safely. Because the science class was held in an existing science room, the only viable safety accommodation was to decrease the maximum class size for any one class assigned to that room. Although no litigation resulted from the accident, the potential for a court finding of negligence by the school was significant. It is important that planning teams and designers be well informed about the research base regarding such accidents. Newspapers often cite accidents in school
classrooms because the accident rate in schools is 10–50 times higher than in the chemical industry (Wood, 1995). Looking beyond the headlines, research reveals the factors that contribute to accidents—lack of adequate working space, teachers without adequate course work preparation, teachers with more than two preparations, poor school discipline, lack of safety measures, and inadequate training.
One key point in school safety litigation is whether “reasonable effort” has been made to provide a safe environment for teachers and students. Reasonable effort means that it is not necessary to use a worst-case scenario for every design. For example, we would not eliminate electrical outlets from a design just because a student could stick a piece of metal in one, but we would place all outlets in appropriate locations, use appropriate circuit breakers, and avoid stray lines.
Defined as “conduct that falls below a standard of care established by law to protect others against an unreasonable risk of harm,” negligence is a common factor in lawsuits. Educators are expected to minimize risks and make reasonable decisions.
Examples of negligence for which lawsuits have been brought include the following:
- Malfeasance, or forcing employees or students to assume unnecessary risk, such as asking students to move chemicals from room to room or requiring teachers to work in unventilated spaces that violate federal, state, or local standards. Litigation focuses on working environments made unsafe by inadequate space, poor ventilation, insufficient supervision of students, a lack of personal protection equipment such as eyewashes and showers, or lack of separate and secure chemical storage.
- Nonfeasance, or failure on the part of school authorities to do what should be done, such as provide adequate facilities or alter the curriculum when facilities are inadequate. In one case, a 14-year-old girl was badly burned while carrying alcohol to light burners in a classroom that was not equipped for laboratory work. The court found against the teacher for inappropriate supervision and against the principal for scheduling the science class in a room with improper and inappropriate facilities (Bush v. Oscoda Area Schools, 1981).
In another case, a Texas chemistry teacher was working alone after school preparing chemicals for the next day’s class. She was seriously injured when she dropped a bottle of concentrated sulfuric acid, slipped in the acid, and fell backwards onto a large piece of glass. In addition to the acid burns, she suffered a long and deep cut in her back. She called for help and a colleague carried her to the nearest shower in the girl’s gym. The lack of a safety shower in the chemistry laboratory was a clear violation of all safety recommendations. The court found that the school had not made a reasonable effort to provide a safe working environment for the science teacher or students (Lubbuck Avalanche Journal, 1989).
The potential for successful lawsuits increases when the district fails to take advantage of opportunities to design and build better facilities. Because no facility can be completely accident-proof, the key is best practice. School districts and planning teams should learn from the recommendations of professionals—reviewing the research base, reading professional publications, and consulting expert school architects can all help planners make good decisions. Above all, the principles of appropriate and safe instructional space design should be the basis of the budgeting and planning processes.
Space: The Final Frontier
When discussing safe facilities, the first and most easily calculated factor is space. Providing adequate space makes sense, and research has provided abundant evidence that it reduces accidents. Research has shown that the number of accidents in school science laboratories increases significantly when the space per student is less than 41 square feet (Young, 1972).
When planning new science classrooms, committees need to remember that class size and space are inversely proportional—as the number of students in the class increases, the square footage of working space per student decreases. Crowded classrooms prevent students from moving away from hazards quickly and teachers from moving around to supervise. Planners must also consider the number of workstations available to students. If a lab has only 20 stations, or a chemistry lab has only 4 sinks or gas outlets, the number of students that can function safely is limited by that facility.
The National Science Teachers Association and the National Science Educational Leadership Association adopted a position statement entitled “Working Conditions for Secondary Classroom Teachers.” This document states that “because of safety considerations and the individual attention needed by students in laboratories, science classes should be limited to 24 students, unless a team of teachers is available” (Biehle, 1999, 30).
The most important aspects of school science facility design are sufficient space and proper arrangement of that space. Most existing science classrooms designed and constructed before the advent of personal computers and the passage of the Americans With Disabilities Act are equipped with fixed laboratory tables. As many classrooms were designed with a 24-foot maximum distance from the corridor wall to the exterior wall, these tables tend to be fairly close together with a 2-foot aisle space between the ends of the tables. Further, to maximize the number of student workstations, the space between rows of fixed tables often has been minimized, in some cases to approximately 3 feet. Science students are not always as careful as they should be and sometimes swing around and bump into other students, causing spills. Narrow aisles between lab tables increase the possibility of such an accident and long, continuous lab tables can make it difficult for a teacher to reach a student who needs emergency assistance.
Older labs also tend to have raised utility racks running down the center of the lab bench that reduce the ability of the teacher to visually supervise the students. NSTA recommends specific minimum areas for science learning spaces with a maximum of 24 students in a laboratory or lab/classroom (Figure 1).
Current science curricula suggest that flexible space with utilities and fixed lab benches on the perimeter of the space will best serve most students. Designing a laboratory area with fingers or banjo-shaped tables protruding from a perimeter countertop requires a lot of space and significantly reduces the flexibility of a space while at the same time increases the safety hazard of working in the space. Dead-ends that are created with fingers or banjos can trap students in an emergency or prevent the teacher from aiding a student in distress.
Another common design that requires even more space and is equally difficult to supervise is a barbell arrangement with round or octagonal tables connected by one or more rectangular isthmuses.
Rooms designed with perimeter counter space and movable tables with sufficient circulation space, on the other hand, can provide one of the safest laboratory environments. However, no one design is perfect, and the drawbacks of each must be considered. Several designs work well if there is sufficient space and the rooms are not overcrowded (Biehle et al, 1999).
Specialized science courses such as chemistry and physics require distinct classroom features such as additional fume hoods and longer lab stations for air track activities. The uniqueness of these specialized courses requires more than the generic flexible design can provide. Chemistry instruction, for example, regularly requires the use of gas as a hot flame source, so flame sources such as alcohol burners that provide cooler flames are inadequate.
Chemistry also requires a large volume of gas for a full year of chemistry investigations. Propane tanks are insufficient to meet this need; therefore, we recommend that all chemistry laboratories be constructed with natural gas utilities.
Physics instruction requires more horizontal work surface than other disciplines for investigations on topics such as light, motion, and waves. Additionally, air track activities require six continuous linear feet of surface space. Storage for physics equipment requires larger individual storage spaces for large pieces of equipment such as a bicycle wheel gyroscope, robotic devices, and a wave motion apparatus.
Separate chemical storerooms that are secure and well ventilated are frequently not included by planners. The safe use, storage, and disposal of hazardous chemicals are required either by federal or state standards. These standards usually include extensive training requirements, proper
labeling of chemicals, and personal protective equipment such as dual eyewashes, showers, goggles, and aprons, all of which must be incorporated in the design of facilities. Safe storage of chemicals requires a dedicated room separate from the prep and equipment storage room. As a rule, approximately 1 square foot of space per student is needed for the chemical storeroom. For example, if the chemical storeroom services two laboratories, each with 24 students, the chemical storeroom should be approximately 50 square feet. No chemicals should ever be stored in the classroom or laboratory. Most accidents documented in newspaper stories involve students stealing chemicals. Therefore, chemicals should be stored in a room that is not accessible to students. Secure chemical storage means that the storage area is not accessible from the ceiling or ductwork. Additionally, lab benches that have separate lockable drawers for students are expensive and are more of a hazard than a benefit. Students can store dangerous materials in them, and separate storage spaces take a great deal of time to search in an emergency. A better alternative is to have lab stations with large lockable storage drawers for teacher use, or no storage areas at all.
At minimum, a student laboratory station or working area should provide 9 square feet of horizontal surface, a 15-inch by 15-inch sink, and water and electrical utilities. Adequate prep and equipment storage rooms greatly enhance science learning. NSTA recommends approximately 9–10 square feet per student of prep/equipment storage area. Supervision (and therefore, safety) of these spaces can be greatly enhanced by view windows between the classroom and the prep room or student project space. Separate entries from the corridor to these spaces should also be provided so that individuals needing access do not disrupt classes in adjacent teaching spaces. Alcoves, extreme rectangular, and non-rectangular (such as round) spaces should be avoided in the layout of a science facility, because these designs create areas that may be difficult for teachers to supervise.
The use of computers in science presents a space problem; if a desktop computer is placed on a lab bench, it takes up approximately 6 square feet of counter space (including the monitor, keyboard and mouse). As most labs were designed with minimal counter space per student, adding a computer further restricts the surface area available for investigations. One solution is to place the computer on a rolling cart that can be docked at a perimeter wall when not in use and wheeled to the lab bench when needed. A computer and cart can take up at least 6 square feet of floor space, not counting the area needed for a person to stand or sit while using the computer. With the narrow aisles of most existing science classrooms, placing a computer on a cart near student work stations can drastically reduce available circulation space and create an obstruction in case of an accident.
The smaller laptop computers are currently more expensive than desktop
computers, but they take up less space and offer more mobility both inside the laboratory and during outside field investigations.
Students in wheelchairs need significant amounts of circulation space to maneuver within a science classroom. The Americans With Disabilities Act (1991) requires schools to provide equivalent experiences for students with disabilities, a term which means that disabled students must be able to participate as fully as possible in the entire learning experience, including labortory work. Therefore, at least one student workstation must be accessible to disabled students; the workstation should have a lower counter and sink height, controls that do not require twisting, and enough space at and around the workstation to maneuver a wheelchair.
Further, if the classroom has specialized equipment such as an eyewash, that equipment must also be accessible to a disabled student. To provide aisle space between tables and at the perimeter for wheelchair passage (a minimum of 32 inches of clearance), classrooms must be designed appropriately.
Other typical safety hazards include obstructed safety showers or eyewash stations within the classroom.
Often these are located in corners, behind other casework, or may be obstructed by furniture. Teachers should avoid safety center units that some casework manufacturers sell that have closed base cabinets, making a headon approach by a person in a wheelchair impossible.
Safety shower/eyewash units should be located near the door to the corridor with enough space on either side to keep the eyewash handle from being accidentally activated by students passing by. The eyewash portion should not have casework beneath it and should be lowered so that the wash jets are 32–34 inches above the floor. Shower handles should be lengthened to not more than 54 inches above the floor.
In summary, safe school science facilities are not difficult to design when properly researched and planned. However, this planning requires a long-term commitment by state agencies, school district boards and administrators, architects, and science teachers to continually update their knowledge. Often it is the science teacher who is expected to be the expert and who has the additional responsibility of either developing a sufficient knowledge base or identifying valid resources that provide recommendations for existing or new facilities. Although existing facilities are severely limited in terms of making significant physical changes, there are safety accommodations that can be made: decreasing class size, adding personal protection equipment such as eyewashes and fume hoods, and providing separate, ventilated chemical storerooms. For either new or renovation construction, it is imperative that tax monies are efficiently spent on designs that ensure a science facility that not only allows but encourages safe and effective science instruction.
Sandra S. West is an associate professor of biology at Southwest Texas State University, San Marcos, Texas 78666-4616; e-mail: swO4@swt.edu; LaMoine L. Motz is the science coordinator at Oakland Schools, 2100 Pontiac Lake Road, Waterford, MI 48328; e-mail: LaMoine.Motz@oakland.kl2.mi.us; and James T. Biehle is the president of Inside/Out Architecture, Inc., 127 West Clinton Place, Kirkwood, MO 63122, contact.
Americans with Disabilities Act Accessibility Guidelines for Buildings and Facilities. 1991. Federal Register 56(144).
Bush v. Oscoda Area Schools. 1981.109 Mich. App.373, 311 N.W.2d 788 (Mich. App. 1981).
Biehle, J. T., L. L. Motz, and S. S. West. 1999. NSTA Guide to School Science Facilities. Arlington, Va.: National Science Teachers Association.
Teacher falling into acid. 1989. Lubbock Avalanche Journal, March 3. 4C.
National Science Teachers Association. 1998. Laboratory Science (1990 position statement). In NSTA Handbook. Arlington, Va.: National Science Teachers Association.
National Science Teachers Association. 1998. Working Conditions for Secondary Classroom Teachers (1990 position statement). In NSTA Handbook. Arlington, Va.: National Science
Wood, D. G. 1995. Safety in School Science Labs.
Young, J. R. 1972. A second survey of safety in Illinois high school laboratories. Journal of Chemical Education 49(l): 55.
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