The Americans with Disabilities Act (ADA) is an evolving process; its impact on schools continues to be felt. There is nothing in the “ADA Accessibility Guidelines for Buildings and Facilities” (ADAAG) or in the Uniform Federal Accessibility Standards that specifically relates to science facilities. Thus, specific applications require judgment on the part of the facility planner.
A major principle of good science facilities planning is to avoid building for a single curricular model. Since continued change in educational trends is inevitable, any plans for science space should allow as much flexibility as possible to avoid the expense and considerable inconvenience of reconfiguring the space later.
Traditionally, the high school program, served by a fully-equipped wing of science rooms, has emphasized divisions between departments. The departmentalized model for high schools has remained the norm because construction costs are reduced when water, gas and special ventilation systems are concentrated in a single area. But as schools have grown in recent years, educators have found that large class sizes are barriers to educational goals. Many high school programs have divided their large student bodies into smaller “houses” of 500 students or less. These operate as schools-within-the-school, with faculty teams teaching only the students in their own houses.
Each house has its own classrooms for social studies, English, mathematics, and other subjects. Equipping each house with its own science area presents a considerable challenge to cost-conscious planning teams since this normally requires that gas, water, and ventilation systems be replicated in several areas of the school.
One way schools have preserved the ability to use either departmentalized or “house” models, while keeping costs down and not sacrificing quality, is by placing their science facilities at the center of a “spoke” or pod configuration (see diagram). This arrangement makes it possible to locate either the houses or the separate departments in each wing with the science department clustered at the center. It also allows future staff to reorganize space to continue serving the student body.
Another important design consideration is clustering related facilities. Grouping science facilities together benefits both teaching and the sharing of equipment and resources. The trend toward integration with other subjects brings the additional advantage of coordinating related programs with portions of the science curriculum and energizing subjects such as mathematics and the applied sciences
In high school, science rooms are almost always specially designed, separate teaching spaces. As in middle schools, the increasing integration of science curricula makes it even more important to ensure that the school’s facilities do not limit the types of subjects and strategies that can be used. Given sufficient space, flexible furniture arrangements, and appropriate equipment, almost any type of science instruction can be possible in most spaces.
Some schools have designed generic laboratories that, with few exceptions, have everything necessary for any science course. This approach has the advantage of allowing curriculum changes and future enrollment growth that ay require changes in the allocation of space. Placing extra conduits for utilities in the floors and walls during construction is an easy way to provide additional flexibility for expansion and future improvements.
The two most commonly used models for science rooms are separate laboratory and classroom space and combination laboratory/classrooms. While an effective science room today is generally expected to accommodate work in all science disciplines, additional laboratories may be desired for specialized or advanced courses such as chemistry or physics that require special equipment, fixtures, ventilation, or other resources.
Class size is an important design factor because it helps determine the amount of space and number of workstations needed. To accommodate current technology needs and teaching practices, a good science room will generally require:
• a minimum of 4 m2 (45 ft2) per student for a stand-alone laboratory, 100 m2 (1,080 ft2) for a class of 24 students
• a minimum of 5 m2 (60 ft2) per student for a combination laboratory/classroom, 134 m2 (1,440 ft2) for a class of 24 students.
The 1990 National Science Teachers Association position statement on laboratory science recommends a maximum class size of 24 students in high school.
An additional space of 1.4 m2 (15 ft2) is needed for each computer station and 1.8 m2 (20 ft2) for a workstation to accommodate a student with disabilities. At least 0.9 m2 (10 ft2) per student is needed for teacher preparation space, equipment storage, and separate chemical storage. Space is also needed for longer-term student projects.
A ceiling height of 3 m (10 ft) is desirable for a science room. This is particularly important for classes in physics, where some investigations may require a high ceiling, and in chemistry, where an investigation may produce clouds of smoke. Using a projection screen that is 1.8 x 2.4 m (6 x 8 ft) won’t work well in a room with a ceiling less than 2.7 m (9 ft) high because tables and desks will block the lower portions of the screen. Under no circumstances should the classroom ceiling be lower than 2.4 m (8 ft).
For safety and flexibility, a rectangular room at least 9 m (30 ft) wide, without alcoves, is recommended. The room should have at least two exits and doorways that accommodate students with physical disabilities.
The Combination Laboratory/Classroom
The combination classroom and laboratory requires a larger room, but it has several advantages over a stand-alone laboratory, including providing maximum instructional options and the most flexible use of space. The combination laboratory/classroom is more in keeping with the best practice recommendations for science instruction where laboratory activities are freely intermingled with classroom instruction.
The two most popular arrangements are:
1. A room with fixed student workstations and a separate section for classroom instruction.
2. A room that has a flexible arrangement, with utilities at the perimeter and movable tables that can form various configurations for laboratory and classroom work.
When designing either kind of room, three key principles of room layout should be observed:
• All students face the teacher when they are in the classroom area.
• Sufficient classroom space is allocated to the students so they can work safely.
• During laboratory activities, the teacher can supervise the students easily and movement around the room is not impeded. Paths for egress are a vital safety factor and must be kept clear.
In all room arrangements, there should be a minimum of 1.2 m (4 ft) between the perimeter counters and the areas for general and group seating, and at least 1.2 m around each grouping of tables. In classroom format, provide a minimum of 2.4 m from the front wall to the first tables. The teacher will then be able to easily move around and have use of a table and equipment.
A classroom area and fixed workstations. Laboratory areas with fixed student work-stations allow the teacher to easily supervise and assist students. Free standing utility islands may serve as complete workstations for four or more students. If the room is large, the islands may be installed at one end of the room. An alternative is a utility island that provides power and utilities to movable laboratory tables that serve as the primary work surfaces when pulled up to the utilities. The latter arrangement permits more flexible use of space.
Installed workstations should always allow an aisle space of at least 1.2 m between the perimeter cabinets and the rows of students.
A popular design for fixed stations is the trifacial utility island (triple table hub), as shown in the diagram. Movable tables are drawn to the three longer sides of these six-sided islands, creating work areas for students who share large, deep sinks that they access from the three narrower sides. Gas, electrical outlets, and computer date wiring can be installed at the three longer sides adjacent to the tables. Each trifacial unit can accommodate three large tables (1220 x 1370 mm [48 x 54 in]) or six small tables (530 x 1370 mm [21 x 54 in]) or (610 x 1370 mm [24 x 54 in]), and thus provide laboratory work space for 12 students.
The tables may be combined and rearranged as necessary to permit activities required in the various disciplines. Tables are available with electrical “pigtails” and outlets that plug into the hub units providing power and data wiring to the far end of the table for computers and other electrical equipment.
Fixed rectangular stations with central sinks can be modified to provide a 1.8 m (6 ft) long work surface, but these sinks are hard to cover because the faucets are in the center of the table. Both types of workstations can be equipped with sockets for apparatus rods, if desired, and outlets for computer network connections. Various storage compartments for supplies and equipment can be installed beneath the counters of these stations.
The classroom portion of the room should be as flexible as possible and provide various arrangements for student seating. Desk and chair combinations, tablet arm chairs, or tables with chairs may be used. The laboratory tables from the trifacial units can be rearranged for the classroom seating, but moving the tables takes some time.
A flexible room arrangement. In the flexible laboratory/classroom, sinks and utilities are located on perimeter counters, and students use movable flat-topped laboratory tables for both classroom and laboratory activities. This design makes the most efficient use of space and renders the room available to a variety of uses. The flexible room is also more easily modified than a laboratory/classroom with fixed workstations or service islands.
Flat-topped tables used as student workstations allow multiple arrangements and combinations for laboratory work and small-group activities that would not be possible with sloping tops.
Two tables, each seating two students on a side, form a workstation when placed together against a counter with the longer table sides perpendicular to the counter. Each group of four students has a sink, a source of heat, such as gas or a hot plate, electric power for equipment and computers, and often, networking connections. The sinks should be installed so that when the tables are drawn up to the counters there is enough space between the
tables for students to easily access the sinks. Gas jets, if used, are between the sinks.
A surface-mounted “raceway” may be installed above the counter’s backsplash to bring in electric power and data outlets at regular intervals along the counter.
The following describes the needs of a flexible laboratory/classroom with movable tables and perimeter counters, sinks and utilities. It also applies to laboratories and laboratory/classrooms with fixed workstations.
Sinks. Sinks for student investigations should be fairly wide and deep (380 x 380 mm [15 x 15 in]) with swiveling gooseneck faucets that allow students to fill and clean large containers. A good rule of thumb is to provide one sink for four students. Resin sinks are recommended because they resist chemical corrosion; however, stainless steel sinks may be an acceptable money-saving alternative in a room used only for programs such as physics, where the use of corrosive chemicals is minimal. Several sinks should be equipped with dual eyewashes.
All sinks should have hot and cold water. This minimizes the need for separate heating facilities in many investigations and improves student hygiene. Schools should be mindful of the maximum temperature for hot water and keep it safely below the scalding point.
Check state and local regulations for hazardous materials to see if special installations are needed. If the program calls for corrosive chemicals, supply the teacher’s sink with an acid dilution trap. This trap is filled with limestone chips that neutralize acid before it enters the regular waste-piping system. A more effective but more expensive method of dealing with corrosive wastes is with an acid-resistant piping system and central acid dilution tank.
Faucets should be equipped with aerators. Serrated nozzles adopted for the attachment of hoses are an option, but they increase the pressure of the water causing splattering. Some of these can be unscrewed, but teachers often respond by attaching a length of rubber hose to them to alleviate the problem.
It is also an advantage to have a large, deep sink with hot and cold water and
adjacent counter space for various purposes such as cleaning large containers. Two very convenient specialty sinks to consider for the laboratory are:
• a “rinseaway” sink, which has a 1.8 to 3 m (6 to 10 ft) long molded fiberglass tray with raised edges that slopes down to a sink basin, facilitating the cleanup of plant and animal specimens. This tray accommodates investigations that need running water, a drain, and require long-term storage. The sink may be equipped with a garbage disposal or a plaster trap to catch sand or gravel. A pullout eyewash sprayer on a hose is useful for both safety and cleaning at the sink, but it cannot substitute for a dual eyewash.
• a deep, enameled-porcelain, wall-mounted janitor’s slop sink, which is very useful for cleaning large containers and filling deep vessels with water. Avoid the typical fixed faucet and opt for a swiveling gooseneck, because the fixed faucet reduces the open area of the bowl.
Glassware drying racks come in various sizes and are often useful if installed above some or all of the perimeter sinks. Mount each rack so that it drains directly into the sink, rather than down the wall. Request a high backsplash, because the drying rack must be mounted high enough to clear the faucet. Some teachers find the fixed drying rack a waste of space and prefer a standard kitchen-counter drying rack that can be removed and stored beneath the sink when not in use.
Work space. For work space, counters 915 mm (36 in.) high and tables 760 mm (30 in.) High are convenient for most students. Countertops should be at least 610 mm (24 in.) deep. A counter depth of 760 mm (30 in.) will provide increased work space. Chairs or stools may be used for seating, but tall stools are not advisable, for safety reasons.
Countertops should be made of resin or a similar chemical-resistant material. They must be caulked using clear silicone between the backsplash and the wall and along any other joints. Standard backsplashes are 100 mm (4 in.) high. They should also run along the counter beside any tall cabinets, all fume hoods, and other surfaces that interrupt or are set into the countertop. Near water sources, always, always use one-piece countertops with backsplashes and no seams.
Flat-topped, movable tables 610 mm (24 in.) wide, 1370 mm (54 in.) long, and 760 mm (30 in.) high can be used for both classroom and laboratory work and may be pushed together to form larger surfaces. The tables should be large enough so two students can sit on one side. Allow at least 200 mm (8 in.) between the bottom of the table and the chair seat. Each student needs a knee space 610 mm wide or as close to it as possible. Most 1220 mm (48 in,) long resin-topped utility tables have knee space only 915 mm (36 in.) wide – not wide enough for two – because the legs at each end reduce the amount of space under the table.
These tables should have tops made of resin or a similar material and equipped with sockets for apparatus rods.
For durability, the best choice is an oak-framed utility table with a resin top. The connection between the leg and table frame is critical for the durability of these other-wise sturdy tables. Many manufacturers lag-bolt the leg to the frame, which often produced failures when the tables are moved around because the leg acts as a lever and pulls the bolt out. A better design bolts the leg to a steel plate set in the frame. In the strongest design, a bolt passing through the plate and leg is held in place with a nut and washer. Since these tables will be subject to a lot of abuse, the strongest table is worth the extra expense.
The resin tops come in white, super white, blush, gray, dark green, dark blue, brown and beige, but these tend to be about 20 percent more expensive than black. The lighter colors may brighten a dark room, but they are subject to discoloration by some of the dyes used in secondary courses.
Casework manufacturers have introduced tops made of of marble-like products similar to those used for kitchen countertops and vanities. These materials are expensive and may be stained by classroom chemicals; they do not have the history of proven chemical resistance that resin has.
Many teachers prefer to use a movable table because they feel that a fixed table at the front of the room separates them from the students and interferes with students’ access to the board. A mobile teacher’s table can have base cabinets, drawers, knee space, and its own water, gas and electrical service.
For safety reasons, workstations for chemistry classes and specialized chemistry laboratories should be at standing height and all stools and chairs should be removed. Biology classes require seating for microscope work.
Physics teachers need a clear work surface at least 1.8 m long for equipment such as air tracks. Many standard designs for science casework should be specified as needed.
Physics teachers aso like long, flat tables with apparatus rods clamped to the edges or fitted into sockets recessed into the top. C-clamp apparatus rods have limited clamp depth and can be used only with tabletops no more than 30 mm (1 ½ in.) thick. Fixed rod sockets should be specified only in cases where they are essential, because they limit flexibility and interrupt the smooth surface of a tabletop making it difficult for students to take notes.
Storage. It is desirable to provide base cabinets and countertops along at least two walls for storage and additional work space. High-quality cabinets, such as those made of marine-grade plywood with plastic laminate fronts, should be a priority. Avoid particleboard assembly for casework because this material is affected by moisture.
Every room needs several types of base cabinets. Consider units with drawers of various sizes, drawer and door units with adjustable shelves, and tote-tray cabinets that allow the teacher to store all items for a class or activity in one bin. Tote-tray cabinets are also useful for storing student laboratory kits that can be brought out at laboratory time and make-up work.
Wall cabinets are typically either 305 mm (12 in.) or 380 mm (15 in.) deep, and should be mounted about 460 mm (18 in.) above the countertop. Bookshelves should be at least 255 mm (10 in.) deep and adjustable to different heights.
Cabinets of various heights and depths are needed for specialized storage of items such as rock and mineral samples for Earth science; a skeleton on a rolling stand, microscopes, and glassware for biology and life science, and stands for aquariums, terrariums, and plants. Physical science makes extensive use of materials and equipment of varying sizes, types and weights.
Allow floor space in the classroom for use of equipment such as laboratory carts, computer carts, an animal cage, and a stream table. It is also important to provide storage for students coats and book bags to keep these items out of the way during lab work.
Display space. Chalkboards, marker boards, and tack boards are hung at roughtly counter height. Dry erase marker boards are often used in place of chalkboards because chalk dust can be harmful to computers and people. However, there is also concern about the toxicity of the permanent markers and manufacturers’ information should be studied. Sliding, multiple-panel
boards can be used to extend a marker board without requiring more wall space.
The instructional focus area may support a variety of presentation formats, including video, laser disc, slides, projected microscope images, and overhead projection. Since a movable teacher’s demonstration table is frequently used, controls, including light dimmers, can be installed in a wall panel easily accessible to the teacher.
Provisions should be made for suspending objects from the ceiling. Tracks with sliding hooks can replace the standard “T-bar” grid of pipes and provide a variety of places for hanging various teaching aids and models. The suspension system for this grid must be much stronger than the typical ceiling grid. A less sophisticated solution is to suspend several 25 mm (1 in.) diameter steel pipes beneath the ceiling using standard pipe clamps, and then to tie or clamp the items to these pipes. The pipes must be suspended from a suitable structure, such as joists from the floor above. The hooks should have at least a 23 kg (50 lb.) Capacity, and each pipe should hold at least 90 kg (200 lb). It is advisable to over-design the suspension system.
Utilities. Classrooms will need plenty of duplex electrical outlets carrying standard household current on separate circuits to avoid overload, all with ground-fault interrupters (GFIs) for safety. Analyze the equipment that will be used to determine if any higher voltages are needed. DC power can be provided by small cells, not automotive storage batteries, or by portable units that plug into AC outlets and are protected by circuit breakers.
To ensure future flexibility for the science program, all classrooms should have wiring with multiple outlets for voice, video, and data network connections. Many schools are using fiberoptic cable for long hallway runs, but most still use copper wire in classrooms. Two-way voice communication between every classroom and the office is essential.
Science rooms need power and data lines at each student workstation. It is never safe to run wires or conduits across a classroom floor to provide power to workstations or equipment in the center of the room. However, there are several ways to provide electric power to these locations:
• Pull-down electric cords, similar to those in automotive shops. These can be arranged as multiple outlets and equipped with computer network outlets. The primary drawbacks of this system are the dangling overhead wires and the tendency of the retractors to pull the cords back quickly, damaging ceiling tiles.
• Power poles, like those popular in open offices. These provide a more permanent arrangement. The primary drawbacks of this system are a lack of flexibility because the poles cannot be moved easily and the relatively fragile nature of the pole systems which are not designed for the type of abuse possible in a classroom.
• Recessed floor boxes that have lids with rotating “wire-management blocks” that open to allow wires to pass through and close when not in use. These boxes contain several power and network-connection outlets. The electrical outlets in the boxes should be raised above the bottom of the floor box to provide additional protection from any spills in that area of the floor. A model is available that holds the outlets vertically, away from the opening of the floor box. Floor boxes should not be located near safety showers or in areas where water and chemicals are used.
Do not use the old tombstone-type floor outlets that are fixed and stick up above the floor because these are tripping hazards and greatly reduce the flexibility of the room. Also avoid floor outlets flush with the floor or hinged brass cover plates that can break off easily, exposing the outlet to dirt and spills.
Extra care should be taken to investigate the pros and cons with respect to safety of each alternative, especially the floor boxes, and to ensure that everyone, including the custodial staff, is informed of procedures for the safe use of the floor boxes.
Gas is used less often than in the past because it is expensive and requires particular caution and diligence. It is primarily used in chemistry. If the science program requires its use, gas should be installed at the perimeter, near the sinks. When gas is provided by a central system, an emergency shut-off valve, activated by pushing a highly visible button, is needed. A central control valve that enables the teacher to shut off the gas in the room is useful.
Emergency shut-off controls for water, electrical service, and gas should be near the teacher’s station, not far from the door, and not easily accessible to students.
Distilled water is used almost daily in high school science, and most schools build in their own still system. Remember to provide storage space for these units in a preparation or storage room.
Fume hoods are used in certain physical science, chemistry, and life science classes and are required in laboratories where hazardous or vaporous chemicals are used. Either a trifacial fume hood or two fume hoods are needed for advanced chemistry classes.
The use of computers in high school science classrooms is growing. It is advisable to provide space and GFI-protected electrical power for as many computers as possible in a room. In designing new construction, one duplex power and data outlet for every four students is a good ration to use. A class of 24 students will need at least six computer docking stations with connection points to the school’s and the district’s computer network. Provide one dedicated 20 amp duplex electrical circuit for every three computers. A desktop computer station, whether mounted on a cart or permanently mounted on a counter, takes about 1.4 m2 (15 ft2) of space.
The location of computer stations depends on the nature of the classroom. Computers should be stationed as far away from chalkboards and sources of water as possible. Desktop computers are often mounted on rolling carts that can be docked at wall stations or moved to any part of the room.
When planning space for the computer carts next to the various table configurations, allow space for the length of the cart, seating at the cart, and clear passage behind the seating. The depth of the docking space should be roughly 1.5 m (5 ft), to accommodate the cart and allow 0.9 m (3 ft) or more of clearance for a seated student. The aisle behind the seated student should be at least 1.5 m wide, to allow free movement behind the cart.
If computers are to be installed at permanent locations, provide counter space no higher than 810 mm (32 in), with knee space beneath. If the power outlet is beneath the counter or a tower unit is being used, leave a 50 mm (2 in,) diameter hole with a rubber grommet in the countertop for the wire connections. Do not mount computers near sinks for two reasons: the most
obvious reason is that computers can be damaged by water. The other is that standard countertops are too high for comfortable computer use.
In response to continued reductions in the prices of laptop computers, many schools are moving toward their use, installing the appropriate wiring and connecting them to the network. The laptops can be locked in the storage room for security and recharging and to avoid the risk of accidental exposure to water or chemicals during laboratory investigations. These laptops will need network cards recognized by the school’s file server. The room would also benefit from having a high-speed printer for reproducing student reports using the laptops.
†—NSTA Pathways to the Science Standards, High School Edition, 1996, by James T. Biehle, LaMoine L. Motz and Sandra S. West
This article originally appeared in The Construction Specifier in October 1999.