Modularity is a recurring request in new lab designs. With the laboratory’s technology needs and space requirements constantly changing, modular design offers the capacity to change a specific laboratory's function simply by moving a few things around or repurposing existing equipment.
Modular design makes it easy to bring in new equipment or remove unwanted equipment without the hassle of a complete redesign, demolition and the associated costs.
However, modularity could cause issues for the tried-and-true workhorses of the standard laboratory. Example: The chemical fume hood, a necessity in almost every lab.
Traditional chemical fume hoods are designed to evacuate noxious or hazardous chemical vapors from the building by physically ducting them through the structure and out of a roof-mounted blower . Unfortunately, in the process of evacuating fumes, a large amount of conditioned (heated or cooled) lab air goes along for the ride. The process is hardly cost effective or green – it is estimated that exhausted air costs $7 to $8 per CFM per year.
In an effort to address issues like this, there are many laboratory equipment products that provide modularity through flexibility.
Ductless fume hoods and enclosures are self-contained and use carbon filtration to efficiently adsorb chemical fumes and vapors. Air that has been scrubbed of these contaminants is then returned to the laboratory. Since the tempered air (heated, cooled, and/or dehumidified) never leaves the building, great energy and budgetary savings are gained. By avoiding ducting to the outside, ductless hoods offer the flexibility of making traditionally stationary units mobile. Furthermore, the wide array of filter types for some ductless hoods and the robust chemical containment and filtration of filtered fume hoods, offer great flexibility for changing hazardous chemical practices.
Ductless hoods come in three different configurations. Ductless Hoods Tier 1 (DH I) are used for nonhazardous chemistry. These are great for staining operations or handling chemicals that are not hazardous but may be a nuisance or cause sensitization. Ductless Hoods Tier II & III (DH II & DH III) can both be used with chemicals and with specific operations the hood manufacturer approves.
Handling hazardous chemicals and their associated vapors through mass airflow typically follows the age-old rule that “the solution to pollution is dilution.” Fortunately, filtration can be used to “green” this philosophy. However, unlike work that produces chemical fumes, work with potent chemical powders, environmental soils, asbestos and similar materials cannot be addressed through mass airflow or carbon filtration. Rather, it requires particulate filters, often in the form of High Efficiency Particulate Air (HEPA) filters.
Self-contained HEPA filtered enclosures provide user protection while handling, opening or processing materials that cannot be controlled through mass airflow and dilution alone. They can often be mounted on existing bench space or on wheeled stands for mobility. Furthermore, these environmental enclosures can be configured with features, suiting them to specific tasks (ie.bag-in/bag-out HEPA filter systems, waste chutes and ULPA filters).
Things you cannot see can indeed cause harm to you, your coworkers, and your laboratory. In this case we are referring to biohazardous aerosols. Often as an effect of simple microbiological processes, gross amounts of aerosolization can occur and is rarely visually noticeable and often is not realized. Such processes are not limited to, but include homogenization, vortexing, pipetting, aspiration, material mixing and transfers, glove removal, using syringes, stirring, and grinding.
These applications call for a specialized hood called a biological safety cabinet (BSC). Evolving from the “laminar flow biohazard hoods” of the 1970’s, these also come in various forms and configurations. A risk assessment will quickly point to which of the variations is required for any given procedure. In brief, Class I BSCs protect the operator and laboratory from the microbiology within. Class II & Class III BSCs protect the operator, laboratory from hazards within and also the process from room contamination. Class III BSCs (biological isolators or glove boxes) provide the maximum level of protection by creating a physical barrier between the work and the operator, but are ungainly to work in.
If chemicals are included with the microbiological work then connecting that BSC to an exhaust system may be required (similar to a chemical fume hood). Flexible BSC designs like the Class II, Type A2 with canopy or the new Class II, Type C1 offer increased flexibility of installation. Only the Type C1 has the flexibility of both installation and containing hazardous biology and chemistry.
The majority of modern laboratories are built with vacuum network lines. However, before tapping into these networks, first determine what kind of work the vacuum will be doing for you and the lab and the potential consequences of using a common vacuum source for your work. Vacuum networks are built into a building’s infrastructure, and once in place offer very little flexibility. Local and lab selected vacuum pumps and systems offer great flexibility and mobility, but come at a cost to the lab’s budget – not the entire building’s budget.
If you perform aspirations on samples containing controlled or infectious materials using a vacuum network, the entire network can become contaminated with hazardous materials. Furthermore, you could cross contaminate the vacuum for the lab next door or on another floor. Consider the cost effectiveness and risk mitigation of using dedicated vacuum systems for such operations.
Also consider the depth of vacuum required for the work. Lyophilization (or freeze drying) requires a considerably deeper vacuum than built-in vacuum networks can provide. Before installing a lyophilizer, concentrator, evaporator or dessicator, know what vacuum levels will be needed and plan accordingly.
Finding a lab without a water system is as difficult as finding water on the parched desert planet of Arrakis (nerdy Frank Herbert’s Dune reference). As soon as lab planning commences, water resources should be understood and communicated. While it can be advantageous to have a large “house” water system installed, water purity and volumetric demand concerns will invariably arise.
It typically is more cost effective to keep house-water to a very basic and maintainable level (RO or ‘gross’ DI (down to 20-10 microsiemens)). Getting laboratory water any cleaner than this from a building’s water supply will be wasteful for two reasons:
Consider the water quality that is needed at point of use and install wall mounted or small bench top water systems that can further polish water to the level needed. This ensures that only the volume of water needed is actually used, and that when used it is the quality required for the laboratory’s operational needs.
Like water, discussed above, all labs use glassware to some extent. Many labs clean their glass by hand, because interns and undergraduates are free, right? There are a couple of pitfalls in using this strategy. First, while their time may be free, it can be used in other, more productive endeavors. Secondly, intern A likely does not wash to the same quality as undergraduate B, or principle investigator C. Finally, hand washing wastes water.
Glassware washers put an end to these concerns, and can be made to be flexible (unlike the dishwasher at home. Under-counter washers can be retrofitted with finishing panels/facades, wheels and quick connect fittings; making them mobile and flexible. Mobility addresses space limitations while adding water saving and repeatability of the washer to multiple lab spaces that use relatively little glassware (thus maximizing the lab’s investment).
* Dependent upon energy prices in your area.
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