Dr. V.K.Maheshwari, M.A (Socio, Phil) B.Sc. M. Ed, Ph.D.
Former Principal, K.L.D.A.V. (P.G) College, Roorkee, India
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.
Types of Science Rooms
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 furniturearrangements, and appropriate equipment, almost any type of science instruction can be possible in most spaces.
Space Requirements
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.
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.
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.
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 trifocal 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
Flexible lab/classroom with computer carts tables for students to easily access the sinks. Gas jets, if used, are between the sinks.
Furnishings
The following describes the needs of a flexible laboratory/classroom with movable tables and perimeter counters, sinks and utilities.
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.
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.
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.
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.
Counter tops should be made of resin or a similar chemical-resistant material. They must be caulked using clear silicone between the back splash and the wall and along any other joints. Standard back splashes 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 counte rtop. 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 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.
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.
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
Sliding panel markerboards with shelving behind 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.
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.
Computers
The use of computers in high school science classrooms is growing. 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.
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 counter top 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 counter tops 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.
Laboratory safety
Laboratory safety is the key to reducing injury and illness. There are many exposures in the laboratory that pose a hazard to your health and you may have never considered them as a hazard before. It is important to have proper training so you, as the employee, are aware of the potential dangers that may threaten your health or life.
Working in a laboratory can be an exciting experience. It can also pose many threats and hazards that a traditional classroom does not. That is why it is important to know your surroundings. Know where the exits to your room are. There may be more than one exit which could be critical in the case of an emergency.
It is also recommended to be aware of the fire extinguishers in location to your laboratory. In order to fight a fire one must undergo the proper training. In the event of a fire, the first response is to evacuate the area and notify the fire department! Any campus phone will initially direct calls to the ISU Police Dept. and from there the fire dept. will be dispatched. Know where the fire alarm is in proximity to your laboratory.
Know What Hazards are Present in Lab
Chemicals can pose a significant hazard. They should be limited to the use under a properly working fume hood. Chemicals can release hazardous vapors which not only harm the environment, but they can be a major health threat. They must be handled carefully and disposed of properly.
When a chemical is in the laboratory, the hazards of that chemical must be communicated to you. According to Occupational Safety and Health Administration (OSHA), a Chemical Hygiene Plan (CHP) is required to relay information regarding procedures, equipment, PPE, and work practices that are capable of protecting employees from health hazards.
Your supervisor is in charge of providing the information contained in the CHP to you.
Suggested guidelines for Lab Safety
The following guidelines have been established to minimize the hazards in a laboratory setting. It is important to take responsibility for your actions and to keep in mind that irresponsible acts could have lasting future effects.
Personal Habits
Do not eat, drink, smoke, chew gum or apply cosmetics, or remove/insert contact lenses while in the laboratory
Do not store food or beverages in the lab or in chemical refrigerator
Do not mouth pipette
Wash hands before leaving laboratory or after handling contaminated material
Chemical Hygiene
Methods and observations used to detect the presence or release of chemicals will be specific to your lab.
A good indication of the presence of a chemical is to rely on your senses.
Some chemicals can only be handled under certain conditions. It is important to use proper handling procedures and practices as advised.
The emergency procedures for chemical accidents is to first evacuate the area and then notify your supervisor, ISU campus police and EHS office if necessary.
Labeling
It is important to know as much about a chemical as possible. The most dangerous substance is the one that has no label. Communicating information is essential in the science field.
MSDS
In addition to labeling in a laboratory, the next most important type of communication regarding hazards is the MSDS. This is the acronym for Material Safety Data Sheet. This will communicate the information necessary regarding hazards associated with chemicals and also biological agents.
The MSDS to every chemical in your lab must be available to you. It may be in a notebook in your labor available over the internet. Make sure you find the location of the MSDSs in your room.
When to use PPE
Chemical usage poses a variety of hazards. They can be flammable, corrosive, even toxic just to name a few. Taking all precautions to avoid physical and/or health problems is the number one goal. You can never be too cautious!
Proper Use of Personal Protective Equipment (PPE)
Knowing how to properly use PPE can be the key to adequate protection. Not only do you want to make sure it is the proper size for you, but also make sure you are wearing it properly. If it is too big or too small, it is not right for you! Let your supervisor know if you need a different size.
Safty against “Sharp”
A sharp is defined as any instrument, tool, or item that has rigid, acute edges, protuberances or corners capable of cutting, piercing, ripping or puncturing such as syringes, blades, and broken glass. Items that have the potential for shattering or breaking are also considered sharps
When using a sharp there is a risk of being cut by the object and possible infection occurring depending on what the sharp was used for. If hypodermic needles are used, special precautions must be taken to reduce the risk of a needlestick. After use of the needle do not recap, place directly in the sharp container.
All sharps must be placed into a rigid, puncture and leak-resistant container that is also impervious to moisture. The sharps container must be labeled either with “Biohazard” or “Infectious Waste”. Do not over fill the sharps container.
When the sharps container is full it must be collected by the EHS office. A waste pick-up form can be completed and a collection can be scheduled.
Signs and Labeling
Chemical labeling has been briefly touched on earlier One must remember that if any chemical is transferred to a secondary container, this container must be labeled. If the chemical will be used by the end of the work shift, then labeling is not necessary. Good science practices would encourage you to label all containers.
Signs
Labs which use recombinant DNA and infectious agents must have a sign posted on the outside of the door. Before someone enters the lab, they will have the information they need to protect themselves. Always read the signs carefully so you know what precautions to take.
Biological Safety Cabinet
The biological safety cabinet (BSC) is used as a containment for infectious agents. The BSC has a HEPA filter in the exhaust system to protect the environment and yourself.
Decontamination
Decontamination is the removal or neutralization of toxic agents or the use of physical or chemical means to remove, inactivate, or destroy living organisms. This includes both sterilization and disinfection.
Decontamination is the responsibility of all laboratory workers. Failure to decontaminate can result in exposure to infectious agents which can cause great illness. Most decontamination can be done by chemicals. This technique is used only when autoclaving is not possible. Continue on to see what would be best for your lab.
Chemicals
There are a variety of chemicals that can be used as an effective method of decontamination. Depending on the agent being used, the method to use may vary along with the contact time. For most organisms, a 1:100 chlorine solution for 10-30 minutes is adequate. The Biosafety Manual has a list of sterilizers/ disinfectants that can be used.
Autoclave
The autoclave is the most effective method to use for decontamination purposes. As a general rule of thumb, autoclave all materials that are considered infectious agent, recombinant DNA, or resemble components of this nature. When in doubt, AUTOCLAVE! If a material is not capable of autoclave because of its size, material, or it is stationary, then rely on chemical disinfectant as a second option.
Spills and Accidents
Spills and accidents can pose a serious health and safety threat. When a spill occurs, an aerosol can be created which can make the material several times more potent. The best measure to take in order to protect yourself is to be prepared. There should be standard operating procedures for this type of situation in your lab.
Being able to recognize the hazards, mitigate the spill, and notifying response authorities can be your best defense. The first response to a spill should be to evacuate the immediate area until the scope of the hazard has been addressed. Seek medical attention if necessary. Allow sufficient time for the aerosol to settle before considering entering the room. If you are responsible for clean up, proper training shall be addressed.
When a spill occurs, it must be reported. Report to your supervisor all spills. If medical attention is needed, it is suggested to go to Student Health Services. All injuries that are a result of a spill must be reported to EHS.
Waste Management
Hazardous and biohazardous waste has special guidelines for proper disposal. It is important to properly dispose of waste to ensure human and environmental health. EPA regulates the waste that is generated at ISU.
Waste can be classified as either hazardous or biohazardous. Let’s take a closer look at the differences.
Hazardous Waste- This is a waste which contains the characteristics of being any of the following:
A biohazardous waste is any waste that is considered infectious and/or because of its biological nature it can cause physical or health hazards in humans, animals, plants or the environment. This includes recombinant DNA and other genetically altered organisms and agents.
Proper Disposal
Waste that is considered biohazardous can be disposed of in regular trash once it has been rendered non-infectious. If a biohazard labeled bag is used, make sure it is either placed in a secondary bag or a completely new bag that is not red. Hazardous waste must be disposed of through the Environmental Health & Safety office.