The primary objective of an educational facility like a school is to teach. The general assumption is that the facility is safe for all occupants. However, of all classrooms within a school, perhaps none offer a range of hazards as wide as chemistry laboratories. Indeed, there are building codes and minimum design requirements that must be met within these settings.
When designing or retrofitting lab facilities, decisions range from the lowest first costs necessary to meet the minimum code requirements to state-of-the-art best practices that increase the safety level desired by a school district.
Regardless if the school is public or private, it takes an informed owner to appreciate the professional engineering and architectural decisions that go into a design that balances cost and safety. The lowest first-cost design and product selection options may increase the risk to those using the facility and laboratories within an educational facility.
Risks and Emergencies
Minimizing risks in the operation of a laboratory to prevent an emergency situation takes a great deal of experience and interaction with the users of a laboratory within educational facilities. The use of various utilities and chemicals must be taken into account. Water and electric are common in other spaces and our daily lives; however, combining those two with various chemicals and the use of open flames increases the risks. The users are mainly students ranging from high school ages to collegiate and graduate level ages.
We have five human “sensors” for hearing, tasting, seeing, smelling, and feeling. These basic sensors are essential in the operation of a lab. Generally, when experiments are being conducted, any or all of our five senses can be used to minimize a risk by triggering a response as needed. If gas is smelled, there is likely a safety procedure to manually shut off a valve, either at the specific experiment location or the room in total. If there is a fire or visual plume due to a chemical reaction, this, too, likely triggers a human response to mediate the risk and prevent a disastrous emergency.
Sometimes an incident of elevated risk requires quick evacuation of a classroom or an entire building. In those times, it is wise to have a protocol in place to quickly shut off any utilities, such as the gas or electric source, that could propagate the situation to a higher level of risk and destruction or cause harm to the occupants. The shutoff can be manual; however, automatic shutoffs may possibly minimize the risk more quickly and save lives.
Technology has advanced throughout the years to provide the opportunity to install early warning sensors that automatically shut off utilities, allowing the instructor and chemistry lab users to be in a safer environment and evacuate more quickly and safely. These technological advancements reduce risks and the likelihood of emergencies.
HVAC Design Considerations
In the spring of 2021, many districts are focused on getting students back in the classrooms. With the realization that COVID-19 and newer coronavirus strands can be airborne, much attention has shifted to update districts’ ventilation systems. In addition to minimum code requirements, many districts are openly discussing implementing technology designed to regulate the amount of outdoor air entering the facility as well as the “cleaning” of indoor air.
Many types of air-cleaning product manufacturers have seized the opportunity to educate potential customers and school districts on the benefits of their products. Whether it be enhanced air particulate filtration with higher MERV ratings; increased outside air volume; or other technologies, such as UVC, the focus is clearly on protecting students and teachers.
It is important to follow the science and engineering of products and not just look at the manufacturers’ warranties but also to look at the performance guarantee that backs up any marketing claim. In general, a warranty is written to limit liability of the manufacturer and not for the protection of the customer. The “Keep It Simple” (KIS) principle has been a cliché in HVAC applications in schools for years. Now is the time for Keep It Defendable (KID) principle in the evaluation of HVAC products and systems. Professional engineers must follow the minimum codes but also be aware of current technologies and best practices that are sometimes part of industry standards but not yet codified.
Design considerations must incorporate the input of all design team members, including the facility owner, those who use the spaces, and those who maintain them. A laboratory space in an educational facility requires an integrated approach during design and construction as well as operation with consideration of risks and potential emergencies.
Although this article focus is on utilities, there is also a need to understand and design for chemicals used within a chemistry lab. More often than not, chemicals used in a chemistry lab are stored in a ventilated cabinet or storage space. Chemical spills or leaks in chemical storage spaces can be problematic. These cabinets and spaces will generally have a dedicated exhaust fan that is of a material that is suited for use with chemicals similar to those used to exhaust from fume hoods (see Figure 1). Exhaust fans for chemistry classroom hoods, chemical storage rooms, and general classrooms are designed to discharge directly up, away from the building to minimize the possibility of the exhaust air entering back into the ventilation system through outside air intakes (see Figure 2).
“SAFE LAB – School Chemistry Laboratory Safety Guide” addresses design considerations. This document, which was published by the U.S. Consumer Product Safety Commission and the National Institute for Occupational Safety and Health, covers many topics dealing with chemical storage and use safety as well as teacher responsibilities and do’s and don’ts for students. The document also discusses guidelines to follow in the event of a chemical spill. All incidences and emergencies can bring into focus liability for the schools in design decisions for chemistry laboratory classrooms.
The design of chemistry classroom laboratories requires consideration of normal operation and emergency situations. It’s necessary to have eyewash stations, safety showers, and fire extinguishers that are suitable for combustible materials and chemical and electric fires. Storage and access to basic personal protective equipment (PPE), like goggles, gloves, and first aid materials, is also a consideration in the design of laboratories. In general, whether a high school or university chemistry lab, the students need to be trained in proper use of the chemicals and what to do in case of emergencies.
Another design consideration is the use of leak detection sensors and cables that can be installed to give early warning of any liquid spills or leaks that may occur in the piping or chemical storage cabinets and spaces within a laboratory space.
Codes and Standards
There are multiple codes and standards that provided guidance and regulations for the products and installations of utility controls within a laboratory.
The National Fire Protection Association (NFPA) has a number of documents related to chemistry classroom laboratories. Many of these are written in code language and adopted by national, state, and local code bodies in their ordinances. These may also be referenced in design guides’ and school systems’ best practices guidelines that architects and engineers take into consideration when they design chemistry labs for specific school districts.
A few of the NFPA documents are noted herein; however, this list is not all inclusive. Some selective verbiage is included for relevance to this article subject matter. The codes and standards do not generally dictate if the controls and accessories must be installed individually within a project or as part of a packaged unit that is factory assembled with convenient wiring, control, and piping connections at the time of installation.
NFPA 101 Life Safety Code states ... “This code requests that consideration be taken in regards to the character of the occupancy, the capabilities of the occupants, and other factors necessary to provide occupants with a reasonable degree of safety — a school classroom, where students are utilizing natural gas and have little or no experience with open flames, should be afforded the utmost safety when designed.”
NFPA 45 states that there should be “an emergency gas shutoff device in an accessible location near one of the egress doors . . . in addition to manual point-of-use valve."
NFPA 54 states that “Each laboratory space containing two or more gas outlets . . . shall have a single shutoff valve through which all such gas outlets are supplied. The shutoff valve shall be located within the laboratory or adjacent to the laboratory's egress door and identified.”
The International Fuel Gas Code states that, for laboratories, “Where provided with two or more fuel gas outlets … each laboratory space in educational, research, commercial, and industrial occupancies shall be provided with a single dedicated shutoff valve. The dedicated shutoff valve shall be readily accessible, located within the laboratory space served, located adjacent to the egress door from the space, and shall be Identified with approved signage . . .”
It is imperative that all applicable codes and relevant industry standards be considered and followed during the design and construction of chemistry laboratory classrooms and that the facility owner be aware of these design considerations.
Organizations and Associations
As with just about any building segment, there are many organizations and associations affiliated with chemistry labs in educational facilities. These groups allow interaction with peers in the same type of industry. They often have written materials for reference and peer group meetings to share ideas and best practices. Many of these cooperatives have transitioned to online learning, which is a blessing to be able to still provide educational opportunities to teach and learn about chemistry lab designs and safety.
One association that has a design guide for reference is the National Science Teachers Association (NSTA). That group’s “Guide to Planning School Science Facilities” is available to help science teachers, district coordinators, administrators, school boards, engineers, and architects. This design guide has practical information on laboratory design, including, but not limited to, current trends and future directions in science education, safety, accessibility, and legal liability considerations. With respect to utilities, this design guide discusses electric and power, heat sources, and other utilities. This document further examines chemical storage, fume hoods, classroom ventilation, and exhausts for these devices and spaces.
The NSTA guide states that manual shut-off switches should be located so that the teacher can easily access them to shut off the electricity, gas, or water in different zones when not needed for science activities. In addition, it is stated that the emergency shut-off controls for electrical or gas service should be highly visible, clearly labeled, and available to the teacher but not easily accessible to the students. Location of all shutoffs requires the integration of multiple design disciplines and installing contractors.
A few specific statements in the NSTA guide are noted herein as relevant to this article subject; however, these should be taken in complete context of the guide: “Emergency shutoff for water, electrical service, and gas should be near the teacher’s station, not far from the door, and not easily accessible to students."
“The control valve for shutting off the gas . . . should be accessible only to the teacher . . . The room should have an emergency shutoff valve activated by pushing a highly visible button with a keyed reset mechanism to turn the gas supply back on."
“Emergency shutoff for electrical service should be available to the teacher but not easily accessible to students.”
Taking advantage of peer groups and guidelines available in the industry makes the decision-making of design options more prudent and indeed defendable for the right reasons.
Utility Safety Sensors and Controls
There are many types of safety sensors and controls for educational chemistry labs. Codes and standards dictate the utilization of each. Many times, an incident can elevate to an emergency due to a lack of sensors, controls, and early warning systems.
Liquid leak detection is not uncommon in educational facilities. Liquid leak detection applications in educational facilities are generally for emergency generator fuel oil leaks, roof drain leaks, and general water piping leaks in sensitive areas that would cause serious damage if the leak is not detected. Liquid leak detection for chemical storage areas in chemistry labs is also a possibility. Liquid leak detection product manufacturers have control panels that can be installed in a chemistry classroom lab to give an early warning of leaks as depicted in Figure 3. These types of systems can have either spot detectors, cable detectors, or a combination of both and can provide feedback of the leak location to minimize the time for response to stop the leak either manually or automatically.
Sensors and controllers can be part of a control contractor’s work with installations pieced together at the job site. In recent years, there have been manufacturers that have packaged sensors and controls into architecturally aesthetically acceptable enclosures with similar concepts as the liquid leak detection units.
Pre-manufactured, packaged units prevent the installation of separate sensors, controllers, and possibly safety valves. These packaged control enclosures are generally locked with access only by those in control of the lab and have panic button devices to completely shut down utilities as a last resort as space is evacuated. Improvements in these products is ongoing to meet the demands of the industry’s codes, standards, and best practices as well as specific building end-user protocols.
Some of the basic components offered include keyed access to the panel, manual and automatic gas, and water and electric shut-off switches and valves. In addition, indicator lights can be incorporated into the face of the panel to indicate the status of each utility. Audible alarms interface with building automation systems (BASs) for alerting the building facility manager and emergency response units are also available.
Most packaged panels by manufacturers incorporate an emergency panic button that can be activated by the person in charge of the space as needed or as the last action as the room is evacuated. Depending on the application, the unit can incorporate a fan control interface to control general space exhaust and fume hood exhausts too. The fan control must be interfaced in some manner with the space total ventilation system so as to keep the proper pressure control in the space. An option with some integrated panels is an automatic shutoff of all the utilities if the space is unoccupied for a period of time based on occupancy sensor input to the control panel.
Some manufactured enclosures have the space and appropriate enclosure UL ratings to include the gas and water solenoid valves and electrical contacts. Some engineers and school design criteria may need or desire to have these in separate panels above an accessible ceiling.
The benefits of packaged utility panels for chemistry classroom laboratories mainly come from the aesthetics of the installation as well as lowering the installation cost compared to piecing together components within steel panels.
There are multiple sources of information on the current technology for sensors and requirements for utilities within educational facility chemistry laboratories. Codes and standards outline the minimums. Industry standards, design guides, and best practices developed by user groups are good to be aware of.
The manufacturers of sensors and controllers are continually improving their products in order to provide safer and more convenient products that add value to the systems. The KIS principle is always good engineering; however, when making design decisions, the KID principle is essential to provide the end user with the performance requirements for each lab.