Biosafety cabinets are essential laboratory equipment designed to handle biohazardous material and are used regularly in various types of laboratories ranging from basic research to high containment facilities. Every Class II biosafety cabinet is categorized by a specific Type—A2, B1, B2, or C1—but how do you know which option is best for your lab? We understand that selecting the right biosafety cabinet is crucial for maintaining a safe and productive laboratory environment.
This presentation will guide you through the ins and outs of the different Class II biosafety cabinet Types, including their respective operating procedures and capabilities. Understanding the differences between each Type will allow you to make an informed decision and ensure the safety of your lab and personnel.
Speakers:
Elizabeth Dille, PhD
Product Manager—Biosafety
Labconco Corp.
This Summit Talk was part of Lab Manager's 2023 Safety Digital Summit.
Lab managers are tasked with keeping their lab staff safe, which means anticipating and mitigating various hazards around the workplace. Heavy equipment, dangerous chemicals, sharp instruments, and mental stress all present varying levels of risk. Managers must develop a comprehensive lab safety program to protect their personnel, equipment, and products—this will help prevent tragedy, as well as benefit a lab’s bottom line by decreasing product loss and costly downtime. What are the steps needed to develop an effective safety program, and how can managers convince their staff to achieve compliance?
Lab Manager recently hosted industry experts who spoke on these issues and more during its Safety Digital Summit. Industry experts shared their personal experience and stories to help you achieve a safer lab. Learn the steps you need to take to properly assess levels of risk in your lab, keep your equipment in working order, and recognize signs of distress among your staff and yourself. Watch for free on-demand to gain the valuable guidance you need as you improve your lab’s experience and create a safer environment.
Hello everyone and thank you for attending Lab Managers Safety Digital Summit. My name is Mary Beth Dena and I'll be moderating this discussion. Welcome to this session, investing in your Lab Safety, how to choose the Best Biosafety Cabinet for long-term success. Please send us your questions or comments at any point during this presentation. Our speaker will address your questions during the q and A session following her presentation. To ask a question or leave a comment, simply type your query into the q and a box on the right hand side of your screen. We'll try to address as many questions as possible during our time together, but if we run out of time, I'll forward any unanswered questions to our speaker and she can respond to you directly. If possible. Lab manager would like to announce that admissions for our Safety Excellence Awards are now open and available for entry. Please see the handout section for more information and a direct link to our Safety Excellence Awards page to learn more. Additional resources and a certificate for this presentation are located on the right hand side of your screen. In the handout section, I'd like to remind you that the recording of this webinar will be available for free on demand viewing after the conclusion of this event. I would also like to extend a special thank you to our sponsors who support Allows Lab Manager to keep these webinars free of charge for our readers. So with that, I'd like to introduce our speaker for this presentation. Elizabeth Dilley is the product manager of Biosafety and powder containing products at Lab Conco Corporation in Kansas City, Missouri. She's actively involved in the design testing and use of Class two biosafety cabinets at Lab Conco. She regularly attends annual biosafety conferences hosted by the American Biological Safety Association International and the Controlled Environment Testing Association. She also maintains knowledge of N SS F ANSI Standard 49. Beth holds a PhD in Molecular and Integrative Physiology from the University of Kansas Medical Center. Beth, thanks for joining us today. Thank you Mary Beth for that introduction. As she discussed, we're gonna talk today about how to choose the best biosafety cabinet for long-term success in your laboratory. A couple of topics that we're gonna discuss today include some we're we're gonna first start with some biosafety requirements, meaning how do you assess biohazards what and what agencies are responsible for biosafety regulations. After that, we're gonna move into biosafety cabinets. We're gonna start with an overview of common laboratory enclosures, and then we're gonna move more specifically into the different classes and types of biosafety cabinets. And we're gonna end kind of discussing each of those types and what their venting requirements are. After that, we'll briefly discuss some selection criteria to consider including operational costs and maintenance costs for the different types of biosafety cabinets. I always like to start out this talk by, by kind of telling, setting the groundwork for what is a biohazard and specifically what are we talking about when it comes to terms of biosafety. In a very general sense, a biohazard is any infectious agent or part thereof that can present a real or possible health hazard to animals, humans, or plants. As we rely on all of these across our life for either sustainability, for food, for companionship, and then just for general public health, we want to make sure that we handle biohazards appropriately so that none of these entities or these different items are infected based on our laboratory work each day. Okay. When it comes to biohazards, there's different ways in which we assess the risk of the microorganism or the cell or the viral particle or the things that we're working with with typically what we look at to classify these biohazards into their specific risk groups are how, um, what is their pathogenicity or transmission to either plants, animals, or humans. So we start to look at what risk does what I'm working with pose to myself, be it the operator or be it the environment around me. Okay? Once you have that kind of risk evaluated, you can then start to assign a biohazard or an application to a risk group. And these are typically referred to as risk groups one through four. Now, this is something people don't hear of very often. More often what you hear about when it in terms of biohazards and biosafety are biosafety levels or BSL levels. Okay? The BSL level, when we hear that some say somebody has like a BSL two lab that they're gonna be working in. What that designation means is not only a designation to the microorganism that they're gonna be working with or the cell or, or whatever their process is, but also what the room has to have. What kind of standards apply to say labeling and signage on the door. Do you need to have a sink? Do you have to have an anti room? Do your doors have to lock? What kind of p p e is required for the user to handle that organism? All of those things kind of are encompassed when we say A B S L level room. B S L one would be the most general, mostly non-pathogenic type bacteria all the way up through what would be a BSL four laboratory, which there are only a few of those across the country. But knowing that BSL level kind of tells you what other things outside of the biosafety cabinet are required to work with your specific biohazard or pathogen. Now how are these classified? Who makes the rules kind of on what these, what these organisms are? And when people call us and ask us these types of questions, the first place I always like to refer them to is to their institutional guidance, be it at a university or you know, pharmaceutical companies. You typically have either an environmental health and safety office or an industrial hygiene group that you work with to make sure you're following all current compliant um, regulations for the different hazards and chemicals that you're working with in your lab. So this is a great place to start. If you have a question, say you wanna use a new vector or a new viral vector in one of your cell lines, this is a great place to go and say, Hey, what do I need? Where do we need to start? What do we need to make sure we do to make sure everyone is safe? Aside from there, there are global biosafety standards. The C D C puts out a book called Biosafety and Molecular and Microbiological and Biomedical Laboratories. The sixth A was released about in the last year or so, and this is a free guide to anyone and it really breaks down certain microorganisms, what their associated risk groups are and what B S L level is associated with those organisms. Within this book, you will also find your lab requirements. What I mean by that is do you have to have specific signage on your door? Do you need a certain air change per hour? What kind of primary engineering controls do you need to use? What kind of p p e is required? Those types of things. Canada also has a similar standard, um, called the uh, BIOSAFETY standard, and then the World Health Organization also puts out a bio biosafety manual. All of these are great resources to look at when you're classifying your biohazards and each one will break it down by the risk group and then provide you with that B S L level and kind of what engineering controls you need in place. Okay, so when, as I work for a manufacturer of laboratory enclosures, we get a lot of calls every day, and the most common question that we hear of is, I need a hood. And this is often kind of leads us in a direction of, well, what kind of hood do you make? Or what kind of hood do you need? We make a lot of different hoods at lab Conco, as do most manufacturers of laboratory enclosures. Most often different laboratory hoods are referred to by different names in different disciplines. Back when I was in a research lab, we had the hood and we had the cell culture hood, so we didn't really call them by any official names. So when I start to think about what kind of hood of customer needs, I like to ask three questions. Okay? First question is, what type of protection is required? So for instance, let's say you were to call in and say, I need a hood, um, to keep, keep my lab safe. We have this process going. I would say, okay, does your, do you need personnel protection for your technician or your researchers? Do you need product protection? Meaning does your product need protected and do you need environmental protection? Okay, the next question I would ask is, what are you trying to protect from? Is it a fume? Is it a powder chemical? Is it a biohazard? All of these different kind of, um, contaminants or all of these different things are gonna lead us to a different type of hood. The last question I would ask is, what are the application requirements? And what I mean specifically by that is how is whatever you're handling, whatever sample it is going to be handled, are there certain processes in that application that might make it a higher risk than others? For example, are you fornicating or are you doing something like that with your hazard? Or is there any specific equipment being used like hot plates or anything like that that also needs to be considered within the enclosure? The most common laboratory enclosure I think that people think of is the chemical fume hood. Most every, um, scientific or general chemistry laboratory has one of these. They are negative pressure enclosures where they draw air in the front and push it out of the building. So this is what we consider negative pressure air is moving past the operator into the enclosure, and that's what's providing personnel protection. Okay. It's very important to understand that when you're working with a biohazard, we do not want to use or handle those in chemical fume hoods. The reason for that is any contaminants or any aerosols generated are gonna be carried outside the exhaust stack and pushed out into the environment. And we all know bacterias, viruses, anything of that nature are still gonna be active when they're out in the environment. So this kind of brings us to the next class of enclosures that we find in labs. Chemical fume hoods are for just that, they're for vaporous hazardous chemicals. There's no kind of filtration in them. Usually some applications do require scrubbers and things in the exhaust system depending on how much chemical is being used, but in general, there's not a lot of filtration. Things are pushed out into the atmosphere and diluted. So that brings us to our next type of enclosures, and those are enclosures that employ what we call our HEPA filters. HEPA filters are designed to trap particulates and they do this very well. Um, a little different than kind of some of your standard filters you might find at home in your house, but similar in some ways. Okay. The first type of HEPA filtered enclosure we commonly see in labs is called a clean bench. These are also known as laminar flow workstations or laminar flow hoods. They are positive pressure, meaning that air is drawn in through the top of the enclosure and then pushed out the front in either a vertical or horizontal manner. And these provide, this type of enclosure is cleaning the air around what you're working with by positive pressure and providing product protection only the airflow in these con enclosures is directed out the front of the hood towards the operator, which means they are not good for hazardous or biohazardous applications. These would be only used for a non-hazardous application. Okay. The next style enclosures we come to are what are generally referred to as HEPA filtered enclosures. You may have heard these called powder containment hoods or, um, vertical vbe, vertical balance enclosures. Again, every discipline has a little bit different word for what they call these hoods. They can also be called class one biosafety cabinets. In this type of enclosure, it's somewhat similar to a fume hood, meaning air moves into the front of the hood and has been pushed through a HEPA filter before it enters the laboratory space. So this is gonna filter out any harmful particulates, okay? If these are not exhausted, they cannot be used with any kind of vaporous chemical. However, sometimes you can put what we call a thimble or canopy connection on these. If you're working with say, a low volume of solvents or if you have samples with nuisance odors so that the odor and, and the small volume of chemical is carried away, the next type of cabinet that we come across would be the biosafety cabinet. And this is where we're gonna focus most of the remaining talk on. So I'm just gonna speak about it briefly right now. These are both negative and positive pressure type enclosures, meaning that airflow is drawn into the front to protect the personnel. However, there's also HEPA filtered downflow air on the inside of the cabinet to protect the product. They're a combination of a clean bench and a HEPA filtered enclosure all in one. And they have two HEPA filters. Typically an exhaust HEPA filter that's gonna protect the room and the environment and the supply HEPA filter, which is going to protect the product inside the enclosure. The last type of laboratory enclosure that we see fairly often, um, is a glove box. Now these can have all types of styles and applications. Um, some of them are HEPA filtered, some of them are just sealed to provide a, um, a specific atmospheric condition inside. Some of them are heated so that you can have, you know, kind of more like an anaerobic chamber for different experiments. But the main overall kind of quality of these is that they have gloves that you reach in so that you don't ever have to directly contact your product and they're fully sealed. Now, like I mentioned, we're gonna spend the remaining portion of this talk talking specifically about the biosafety cabinets. So what makes a biosafety cabinet, a biosafety cabinet on the right, you can see an image of what a standard kind of biosafety cabinet looks like. These are protective enclosures for safe handling of biohazardous materials. And again, just like we talked about in the beginning, this would be bacteria, viruses, human cell lines, molds, fungus, anything like that. And these different BSEs can provide different levels of of protection. For instance, a class one B S C provides only personnel protection and environment protection by exhausting all of the air through the HEPA filter as it moves through the hood. The class two B S C protects two levels of, provides two levels of protection. It protects the personnel. As you can see on the image in the top right corner. Airflow is drawn into the front of the hood to protect the person from anything they're handling inside. And then there's also product protection as well as the downflow air. You can see this an image, a video of this on the bottom right side of the screen. This HEPA filtered air bathes the product to protect it from any contamination from our lab environment. All of the air is exhausted out of a HEPA filter. So that is what provides the environmental protection for the lab. Common applications where we see these types of enclosures required, I would say probably the most common in research and even in pharmaceutical areas would be cell and tissue culture. We're usually working with some kind of cell line, be it from an animal or a human cell line that we are treating with either a compound or a drug, or maybe you're adding viral vectors or things like that to see what happens to development of those cells over time. They're very common in microbiology labs as well as in pathology and necropsy labs. Sometimes what we're doing is harvesting samples or working with maybe patient samples in a hospital that we don't want to get contaminated. And we also want to protect ourself from clinical diagnostics. Sometimes have these, um, bscs in their spaces as well as in pharmacy compounding. Anytime hazardous drugs are being compounded into like an IV form for a patient, they would do this type of work in a vented biosafety cabinet. So within the world of biosafety cabinets, we like to classify them first by class and then second by type. Okay, so you might've heard of a class one B S C or a class three B S C. So what that means is how the airflow is moving through the hood and what it is protecting. I like to think of it in a way that a Class one B S C protects one thing. It protects the personnel from what they're working with. These are HEPA filtered and negative pressure enclosures. A class two B S C provides two levels of protection. It provides both the personnel protection of a class one B S C, but it also provides a second level of product protection with that HEPA filter, downflow air. And then there's what's called a class three B SS C. This is a glove box style, fully enclosed design. So it has the, the gloves on the front. They can operate under negative and positive pressure, provide personnel and product protection. The, the exhaust of these um, units is usually double filtered and there's also usually some kind of anti chamber that provides sterilization via gas or something like that. Or they'll have a dunk type chamber where all of the, anything going in or out of the glove box is taken through a liquid bath of disinfectant. Of all of these types, the by far the most common that we see for applications is the class two biosafety cabinet. So the next check section of this talk, we're gonna focus on the different types of class two biosafety cabinets. Now before we get to those types, how do we know what type is what? There is a standard out there that exists and covers most of the US and international groups. Different countries also have similar standards that are listed, um, for country. But in the US we typically follow what is called N SS F ANSI standard 49. This standard is put out by the National Sanitation Foundation International and it's kind of the globally recognized design standard for manufacturing and testing of class two bscs N SS F outlines very strict um, performance requirements. These cabinets go through biological challenges where they actually use, uh, bacterial spores from BACILLUS to test to make sure anything inside the cabinet does not get out and things outside the cabinet do not get in. They list the requirements of how an A class two type A to B or C need to work specifically. And I put a little link here on the screen. This link will take you to a little kind of knowledge library that the N SS F has put together that summarizes these different types in their applications. Other resources also exist that tell you about biosafety cabinets and their uses. In the section of the B M B L guide that I talked about earlier from the C D C, there is a section that talks about biosafety cabinets. The W H O Biosafety manual also speaks of different classes of biosafety cabinets in their usage. And then there's also a guide that's put out mostly for those people that go around and test and certify cabinets called C D A application guides that talk about how the cabinets should be tested, how often they should be tested and if they're exhausted, how those exhaust requirements should work. Okay, so what makes up a biosafety cabinet in general, no matter because of these specific design standards that all manufacturers have to meet, overall anatomy of a biosafety cabinet is fairly similar across different manufacturers. They're all going to have some type of inlet airfoil in the front, which is gonna pull airflow into the front. And then under the work surface, we don't want any contaminated air going across the work surface in a class two B S C 'cause that would contaminate our product. So it's gonna have an inlet grill that pulls air under the work surface. These work surfaces are usually removable because you often need to clean under them, especially if you're doing any kind of animal work or any handling any kind of animal or animal bedding or cages that have animal bedding. They're most all are stainless steel or powder coated steel construction. And sometimes they will have different service fixtures pass through ports, UV bulbs or different accessories on the inside of them as well. They will all have a protect protective glass sash that moves up and down so you can close the unit when not in operation. And each B S C is going to have a very specific sash height at which it must operate. It's not like a fume hood where you can kind of have the sash at different positions depending on how your hood's set up. Biosafety cabinets have a very strict sash height position. And then some biosafety cabinets, which we'll get into this more, um, can be exhausted outside depending on your application. So this would be removing air, removing the air that goes through the cabinet and pushing it outside the building. And then typically biosafety cabinets are on some sort of base stand. That's an adjustable height, telescoping base stand or hydraulic stands that can be raised up and down the internal parts of a biosafety cabinet as far as what's happening up top to make all the air move. These are gonna be different for each type of biosafety cabinet. However, in general, they're all going to have an exhaust HEPA filter. So this is gonna filter all the air leaving the cabinet. They're going to have a supply HEPA filter. This is what's gonna provide that downflow air, that sterile downflow air that protects our product in a class two B S C. They're gonna have one or two blowers and then one or two plenums. A plenum is simply a word for an area where air is pushed or decided to move in a certain direction. Okay, now how do these operate? So the class two bscs we talked about provide both personnel and product protection. For the personnel protection room. Air is drawn into the front of the biosafety cabinet, moves under the work surface up to that shared plenum, and then some of it is pushed out through the exhaust or some of that air can come back down. The inflow into these cabinets is determined by N SS F, so we don't get to change that. Your manufacturer will tell you what that inflow is, and if they're N SS F listed cabinets, that inflow would be a hundred to 110 feet per minute. That's how fast the air is moving into the front of the cabinet. The downflow air, the air that's providing that Peppa filtered product protection inside the cabinet can vary and each manufacturer will tell you how fast that needs to be to maintain containment. This is typically anywhere from 50 to 80 feet per minute from the inside of a cabinet. This is what that HEPA filter downflow air looks like if we put a little smoke across the cabinet inside the cabinet. So as this HEPA filtered air comes down, it bathes the work surface. And one thing you'll notice in this video is that some of the smoke goes to the front a cabinet and in that inlet grill and out and some of the smoke goes to the back of the cabinet. This area where the smoke kind of splits is called the smoke split overall. That is how all of these different types of biosafety cabinets, they're all gonna have kind of similar um, features like we just talked about. However, within the class two biosafety cabinet world, there are different types of cabinets and they're defined by type. Nowadays the most common four types that are known would be a class two type A two A, class two type B one A class two type B two or a class two type C one. There are other cabinets out there such as the A slash B three type, which are really no longer made by manufacturers as they've just been kind of replaced with one of these common types. The main question you need to ask yourself when determining which type is best for me really boils down to one question. And that is, are you using any fuming or volatile chemicals? And how much of those chemicals are being used? Now, we're gonna discuss this a little bit further as we get into these different types of bscs, but basically in this next session when I dis in this next section, when I discuss each of these cabinet types, really what we're gonna be talking about is how they handle the exhaust air. Okay? So first we're gonna start with the class two type A two biosafety cabinet. This is the biosafety cabinet type that I've referred to in most of my drawings, and it is by far the most common biosafety cabinet type out in the world today. This is the most common B S, C for any biohazard application, and it can make these bscs irrelevant for BSL one through four labs. Okay? Airflow is drawn in the front as we've already discussed, and then some of that airflow is pushed back down through a HEPA filter or pushed out the top to protect the laboratory space. Now, I just said this will work for most all biohazards and applications. So why do we need all of those other types of biosafety cabinets? Well, what really happens in a lot of cell tissue work and microbiology work is that we're not using any hazardous chemicals or vapors, and that's why these cabinets are applicable for any of our biohazard work that doesn't involve these other hazardous chemicals. The reason for that is, is HEPA filters will trap all of the part, the biohazardous matter generated in a cabinet and provide adequate protection. However, what HEPA filters cannot do is trap chemical vapors. So if you're working with something, say phenol, chloroform or triol for, you know, d n a or r n a extractions, we don't want those vapors of those chemicals passing back into the laboratory space. So this is when we need to start thinking about how can we exhaust a biosafety cabinet. So what happens when we have these chemical vapors? That's when we really get into the next chunk of the talk on the types of biosafety cabinets and how we're going to handle those in our lab space. The first thing that we can do is just take our class two, type A two biosafety cabinet that we've had for all of our cell work, and we can put what's called a canopy, or also known as a thimble connection on top of the unit. And this would allow us to connect to a general lab exhaust system and exhaust out those fumes. These, these canopy connections or thimble connections are specific to the cabinet type that you have. So you need to work with a, you can't get, you know, say a, a canopy connection from one manufacturer and put it on another cabinet. The reason for this is this canopy and any exhaust failure alarms must work with the cabinet. So each model of cabinet out there is gonna have the specific canopy type connection that will allow it to wire to the biosafety cabinet. This is all per that N S F standard 49. That tells us how biosafety cabinets must work. Okay? Now if we look at the B M B L guides and the NSF 49 guides on what type of processes or applications an A two with a canopy can cover, it says that canopy A twos can work for applications that require small volumes of chemicals. Now, it's hard to determine what a small volume of chemical is when we're looking at it could be five mils of one chemical could be a lot more hazardous than five mils of another. So this is really comes down to your risk assessment and if this type of hood would work for you. A couple of the things to remember about this type of camp cabinet set up as it's exhausted out is, remember in an A two style cabinet, some of our airflow is recirculated within the cabinet. This means that it's possible that we could have an increase in the amount of concentration of our chemical within the hood over time. Some of the airflow is coming back down through the HEPA filter while some is being exhausted. This is one of the reasons why only very small volumes of chemicals are appropriate. This type of canopy connection on an A two is also applicable if you're just trying to exhaust out, say, nuisance odor from the samples that you're working with. Okay, so some of the pros and cons of the Type A two cabinet, the pros are this is the most common cabinet for working with biohazards. Another pro, uh, good spot is that it can be manifolded with other ventilation, other lab hoods should you need to provide exhaust for very low volumes of chemicals. They also, compared to the hoods we're gonna talk about next, have a lower exhaust volume of air. Conditioned air is very expensive to make in a laboratory. So when you're having enclosures that are just exhausting this conditioned air outside, it can start to play into your long-term maintenance costs. So an canopy, A two exhausts a lower volume of air compared to other cabinets. Some of the cons of the Type A cabinet are that they're really only for applications without fuming or hazardous chemicals. Okay? If exhausted, they're only applicable for those applications with small volumes of chemicals, right? So what happens if your application changes or you have to ramp up your process and use more chemical than what you're comfortable with? The other downside of the A is that there're always gonna be that style of cabinet. You cannot convert it into A B S C that will work with a larger volume of chemicals. Another downside of the A's is if the remote exhaust fails, which is pulling those fumes out of the laboratory space, there is a risk of chemical exposure. N S F tells us that operational standard tells us that a biosafety cabinet must perform and maintain biosafety must maintain those biohazards in the event of a remote exhaust failure for the class two type A two. This means that some of the chemicals as it has to keep exhausting that air, some of the chemicals may come out of the top of the canopy. This will maintain your biocon containment 'cause that's the number one priority. But there is a risk of some of those chemical fumes coming into the laboratory. So what happens? We need to, so we know maybe you've established that the the class two type A two exhausted is not appropriate for your volume of chemicals. What are the other cabinets out there and how do they function? The next type of cabinet would be called the class two Type B one. This cabinet works a little bit similar to an A, but in that terms is it really only recirculates the air and that comes in that blue portion of the cabinet there. So you'll see in the drawing that I have on the right, there's a blue portion of the air foil in the front. So that initial clean air that's coming from the lab that doesn't have any chemicals in it will be recirculated back down through the cabinet. Now the rear of the cabinet, more to where the red area is, this air, the air that falls that way from the smoke split, it's gonna be directly a hundred percent exhaust outside, meaning it's not gonna recirculate through the cabinet. So this smoke split, remember the video I showed earlier with that downflow air where some air went to the front and some air went to the back? Determines where chemicals can be handled safely, you would need to be sure you're working in the back of the cabinet behind that smoke split line to make sure all of your chemicals are 100% exhausted. Unlike the class two type A two, these cabinets cannot be combined with general laboratory exhaust systems. They must have their own dedicated, um, exhaust blower for each B SS C in their own independent exhaust run. They also rely on that remote exhaust blower out there on the roof to provide the inflow air for the cabinet. So they rely on that remote blower to function. This cabinet will is required by N SS F to shut down within 15 seconds of an exhaust system failure, meaning that if my remote blower out on the roof that is providing all my personnel protection stops, I have to also shut down my internal blower, which is providing that HEPA filter downflow air. So as such, within 15 seconds of that system failure failure, the next type of class two cabinet would be the class two type B two. We just talked about the B one. Now this is the different type of a B two. These are considered full 100% exhaust cabinets, unlike the B one that recirculated some air in the front of the cabinet. All of the air that's drawn into this cabinet be providing personnel protection in the front, or the product protection that's coming down from the top is 100% exhausted out of the cabinet. No air is ever recirculated within the cabinet. Now this provides a very high level of chemical protection similar to that of a chemical fume hood. It's all single pass air single pass out on exhaust. The downside of this is that's a very, that's a lot of air that we're pulling from our laboratory and pushing outside. So class two type B two cabinets require a lot of airflow through the cabinet. They also rely on a remote blower, just like a B one. They have each have should have their own remote blower to function out on the roof. This blower, similar to the class two, type B one needs to shut down within 15 seconds if the exhaust system fails. Okay, the internal blower providing that downflow air must be linked to the outside blower so it knows to shut off should there be a failure within a B two cabinet. As I discussed earlier, all of the air is exhausted to the outside. Now I've mentioned several times that B two cabinets require a dedicated exhaust run and a dedicated exhaust blower for function. These recommendations do not come from us as the manufacturer. They come from that N S F standard 49 where, which says each BSS class two type B B S C should have a dedicated duct work and exhaust blower for each B S C, the C A standard for exhaust system requirements of class two bio safety cabinets also specifies that bio, that class two type B biosafety cabinets must have dedicated duct work and exhaust blowers for each P S C. There's another laboratory ventilation standard out there called ANZ Z 9.5, which also directs if you have more questions about general laboratory ventilation. So the pros and cons of the class two, type B B ss C overall class two type B two class two type B two bscs provide dedicated exhaust to maximize chemical safety for larger volumes of chemicals. However, the downside are there's some operational and safety issues with that remote blower. In event of an exhaust failure. It is possible that when that remote blower fails and the internal blower doesn't wind down fast enough that you could have some chemical exposure and bio exposure out the front of the cabinet. Another downside is that these must have dedicated exhaust runs for B Ss per each biosafety cabinet. This leads to higher design cost and higher installation costs and high operational cost. 'cause the amount of air being exhausted by these cabinets is over twice that of a traditional A two style cabinet. And there's no flexibility within this cabinet. You can't have a B two exhausting chemicals and then say, well my application's changed. I really don't wanna exhaust this cabinet anymore. Can I turn it into a class two, type A two? That doesn't exist because the B two requires that remote blower for exhaust. And so that leads us to the third type of class two biosafety cabinet and that would be the class two type C one. This cabinet operates in different modes. Okay, so it's a little different than the A. It's not really a B, but it's kind of the best of both of those. The first mode it can operate in is what's called a mode. And this is where the entire work surface and area recirculates back to the lab. This would be very similar to a class two type A two biosafety cabinet. If the cabinet is hooked up to a general exhaust and certified and programmed to run. Then in type B mode only a small portion of the work surface is actually 100% exhaust. The work surface in these cabinets are kind of dished in the center and provide 100% chemical exhaust within this area. That area is highlighted in the image on the left in the red area. The other portions of the cabinet, which would be the front and the sides recirculate within the cabinet, which means we have less C F M being exhausted over time. This cabinet also gives you the ability to, as your processes might change down the road or your project changes, you know, after a certain amount of time you can switch it from recirculating to the lab or you can to connect it to duct work. It's a fairly easy connection to make. Would take a certifier about 15 or 20 minutes to make that connection and then they would just need to go back through and recertify the cabinet. The advantages that this provides are, one, it provides reduced C F M when it's exhausted compared to a class two type B two cabinet. In fact, it's a little over half the amount of C F M. And this cabinet also kind of gives us another safety, um, aspect over the traditional A twos and B twos and that because these cabinets have two blowers, they have an exhaust blower and a supply blower inside of them. Should our remote blower fail, the exhaust blower within the cabinet knows to speed up and will run and it starts a countdown for the user. That can be for up to five minutes that tells them, Hey, we've got an exhaust issue happening. I need you to get your chemicals capped and get everything kind of wiped down and cleaned quickly because I can only maintain pushing this airflow through the duct work for so long. So it gives the users a chance to know, hey, I have to, I have to clean up and stop my application and get ahold of someone 'cause my cabinet's having a problem. So it mitigates that possible chemical exposure that can occur during a remote exhaust failure. This is a little bit of what these cabinets look like. You can see in the photograph on the right that dished area within the center work area. So that is the area that when the cabinet is hooked to exhaust provides 100% exhaust volume. And this is denoted in the image on the left in red and you can see just a little bit in the top portion of the red that there is a blower kind of tipped on its side in that area that helps provide that exhaust. And then the blue area would be the area that recirculates similar to an A mode or an A two when the cabinet is exhausted. This cabinet does still require a remote remote blower, but it can be connected to a general exhaust system with other cabinets. So just to recap quickly on these three types of cabinets. Overall, the class two type A two biosafety cabinet is the most common B, S, C, and it's acceptable for all biosafety level use. It can be vented for small volumes of chemicals or nuisance odors. The class two type B two is a 100% exhaust design used for high volumes of chemical use. These have an upwards, uh, expensive installation cost and a high install, uh, operating cost due to the CFMs that are required. The class two type C one is a flexible alternative that combines the benefits of an A and the benefits of a B. The installation is somewhat easy compared to a B two when you need to exhaust them. And then it does provide additional safety features over A twos and B twos when it comes to chemical safety. So this is just kind of a, a summary slide of the chemical safety that we find in class two bscs. We'll see that on the left, on the top we have the cabinet type and then on the left we have different aspects of chemical safety. The first row is it suitable for use with chemicals. You'll see that just the traditional A two is not suitable for that application. However, with a canopy installed, you can use small volumes of chemicals. The B one, B two and C one are all suitable for chemical use. Single pass airflow. The ca, the class two type A two and class two type B one do have some air that's recirculated, okay, throughout the cabinet. The B two is 100% exhaust and the C one is 100% exhaust in the work surface area in the center work surface area. Intuitive workspaces. So sometimes we get questions about, well, how do I know where I'm supposed to be working in my biosafety cabinet in an A two? Since all of the air is handled and you're not having any chemicals and it's recirculating back to the lab, you can work across the full volume of the work surface, typically in a, in a fashion of right to left or left to right, clean to dirty. An A two with a canopy is very similar in a B one. You have to make sure that if you're handling any of those chemicals, you're working back behind that smoke split in your cabinet where those chemicals are A class B two, you can kind of work anywhere on the work surface. And then the C one, the work surface is dish to allow you to know where chemicals can be used as far as how easy they are to vent. Typically laboratory enclosures are considered easy to vent if they can be hooked up to a general exhaust system. This would apply to the A two with canopies and the C one. However, the class type class two type B one and type B two cabinets each require their own blower and their own dedicated exhaust run per those standards that we discussed. The last point I like to make is all of these cabinets have their fault should there be at some type of remote exhaust failure that they don't pro, they can't provide adequate chemical protection during that time except for the class C one. The Class C one has that internal exhaust blower that can step up and speed up and help provide short-term chemical protection in the event of a remote exhaust failure. For the last couple minutes of my talk, I just wanna quickly discuss some of the cost of ownership associated with class two biosafety cabinets. First is the ongoing maintenance. Typically, in most situations, biosafety cabinets are certified annually. However, in high containment facilities, G M P facilities or pharmacies, this can be either six months or more often during these certifications, they're gonna test for HEPA filter leaks. They're gonna make sure the inflow and downflow is what the manufacturer specifies it should be. And they're gonna look for any unusual wear and tear on the sash. The sash tracks, the sash hinges, things like that. Make sure the cabinet's functioning as it should. Typically in a biosafety cabinet, your HEPA filters should last from five to 10 years. It's not uncommon in clean laboratories for, um, HEPA filters to last the life of the cabinet, which can be 15 to 20 years. Always ask your manufacturer when you're looking at purchasing a cabinet, how long they expect their HEPA filters to last. This can vary, but in general, um, most cabinets can have HEPA filters that can last quite a while. Now we talked a little bit about the exhaust on all these cabinets, but what that really comes down to from an operational cost is that the more air that a cabinet exhaust, the more supply air and the more conditioned air that's gonna be have, have to be made for a space. And heating or cooling air can be very expensive. So what really comes into play here when we start to look at these different cabinets is the overall, um, cost of these cabinets over the lifetime of the cabinets. Installation costs, for instance, can be fairly low on an A two or an A two with a canopy. However, that increases with a B two. The maintenance cost over the life of a cabinet is usually the same. They all need certified and they're all gonna need HEPA filter changes eventually. However, the operational cost is where we really start to see a difference. And this is where all of that airflow that we're exhausting comes into a play. So the a the the A two with a canopy and the B one and the C one cost about the same 'cause they both have those reduced, um, air volumes. However, a B two can be very expensive to run upwards to twice that of what a standard A two with canopy or C one. Overall, the estimated operational cost of an exhausted B S C is about twice for a class two type B two than it is for a class two A two with a canopy or a class two type C one. So in conclusion of my talk today, we talked about biosafety requirements, how to assess those requirements, different laboratory enclosures. We talked about class one and class two biosafety cabinets. We talked about the different types of class two biosafety cabinets as well as their ventilation requirements, and then some things to consider as far as operational and maintenance costs. I realized that this was a lot to cover today, so should you have any questions, please filter to reach out after the webinar, we have put together a brief poll, so if you would like to fill that out, that will help guide our future talks to make sure we're we're, we're telling you things you wanna know. So at this time I'll take any questions. Okay, great. Thanks very much Beth, for a wonderful presentation. Uh, as you mentioned, that poll is now to our audience. So we invite you to let us know, um, what you enjoyed in this webinar, what you were hoping we would cover, um, and if you have any further feedback for us. Um, so we are about ready to move into the question and answer portion of our webinar. A reminder for those of you who may have joined us late, you can send in your questions by typing 'em into the q and a box on the right hand side of your screen. Um, so in addition to the poll, uh, that, uh, Beth has mentioned, um, we also have another poll from Lab Manager that I will launch in a moment. After you get a chance to answer Vet's poll, um, we do have a, a poll you can answer for a chance to win a gift card courtesy of Lab Manager. And that poll question will be, what safety measures do you believe deserves more attention in laboratories? So I will launch that now when we invite you to make your choice for a chance to win a gift card courtesy of Lab Manager. And as Beth said, we invite your feedback about, uh, whatever was covered in today's webinar or what you were hoping would be covered, so that way, uh, we're sure to include that information in the future. Um, another reminder, please visit the handout section on the right hand side of your screen for supporting information. This webinar, we also have more information about our Safety Excellence Awards, which you see on the screen in front of you, as well as our Lab Manager Academy Safety certificate program. Uh, I am again gonna put lab Conco contact information up on the screen in front of you. That way if you have any questions following this presentation, if we're not able to get to them, you can reach out to Lab Conco afterward with that information. Um, so Beth, thanks again. We have maybe about 10 minutes left for questions. Uh, let's start the first one up at the top here and then we'll go to some of the others. This one says, can I use my B S C as a fume hood if it's exhausted? Wow, that's a really great question and one that we get often and once a lot of times, especially in a small lab space where you might be deciding, do I need a biosafety cabinet or can I exhaust my biosafety cabinet and still use it as a fume hood? If all of that air is going outside, why can't I use it as both? And the question really comes down to, it depends as most things, um, as most questions do in a lab. But you have to remember that biosafety cabinets are made out of steel, specifically stainless steel, and then even some are epoxy coated, cold rolled steel. So for those types of cabinets, you really wanna make sure you avoid any harsh acids, um, or oxidizers as they are going to eat into and degrade the cabinet over time. So again, the answer it kind of varies. I would recommend always using a fume hood for all those fume hood type applications. Okay, great. Thanks Beth. Uh, we're gonna jump around a little bit. Um, if you look at question 11, this one says, is UV light and a BSC two really effective for sterilizing the BSC interior's surface and contents? That's a really great question and it's, it's come to our, you know, some, some people have to have UV lights in their cabinets, and then there's institutions like the N I H that don't allow UV lamps in their cabinets anymore. And it comes down to the fact, again, as how effective is UV at decontamination? And again, it depends. There's a couple things at play here when we talk about UV bulbs. First is that as a UV bulb, ages its energy level or its ability to disinfect decreases. So if you wanna use a UV bulb for kind of disinfecting your work surface, you need to make sure you monitor that over the life of the cabinet because different microbes are gonna need longer exposure at that energy to actually inactivate them. The second thing to consider is UV light doesn't reflect. And what I mean by that is if you have a lot of things in your cabinet that are blocking any sources of that light, those areas that are kind of shadowed or shaded are not gonna be affected by the uv, which means they're not gonna be decontaminated. The third thing I like to consider when people ask about this is kind of back into that UV bulb thing in the beginning, and you really have to think about what microbe do I have? What am I trying to clean against? You know, what am I doing? I think as, uh, UV bulbs have a great place for genomic applications because they're really good at denaturing d n a. So if you're doing a lot of P C R or reactions like that in your hood where you're worried about secondary decontamination of D N A and breaking those strands, I think UV bulbs work great. However, when people are using 'em for de decontamination of their cabinet, it always gives me pause because you should be using your primary disinfectant that you've selected specifically for your microbe for disinfection. Sometimes UV bulbs can lead to a little bit of a a, a comfort that that things are being contaminated when they decontaminated, when they may not be. Okay, great. Thanks Beth. Um, again, let's jump around a little bit. Uh, let's go to question number four. This one says, how do I know what B SS C is best for my specific biohazard? That's a really good question as well. And biosafety cabinets have HEPA filters that work really well and trap biohazards. So as we talked about in the beginning of the talk, we have those risk group levels and you will find class two type A two biosafety cabinets that are not vented in B BSL four labs. The biosafety cabinets, be it class one or two will protect against the biohazard. However, as you get to those higher B S L levels or those more risky biohazardous substances or processes or chemicals or viruses, you need to start thinking about what other things you have to have in play. Like as far as you know, a BSL three level lab is gonna require you possibly to wear a mask, a full face protection, maybe a PAP R device, a personal respiratory device, and then in a BSL four lab, you're gonna, you can use that same class two type A two, however, you're gonna be in a full positive pressure suit to protect yourself again from those viruses. So the cabinet doesn't necessarily change per the biohazard, but the P p E requirement does. Okay, great. Thanks. Um, mm-hmm. Looking at the clock, we have time for let's say maybe two more questions, but we'll see. Um, we'll see how far we got. Let's look at question number nine. This one says, I'm curious what the pros and cons for HEPA versus ULPA for clean benches are. Okay. Anytime you're looking at HEPA and ULPA filters, HEPA filters and ALPA ALPA filters are very similar. Alta ALPA filters have thicker and deeper media beds than what a HEPA filter does, and it really comes down to their ratings. So a HEPA filter, let's say is, uh, 99.99% effective at 0.3 microns, whereas an ALPA filter will say it's 99.999% effective at 0.12 microns, I believe are the, the specific numbers. So it really depends on your application. For majority of biohazard applications, HEPA filters are used. Sometimes ALPA filters are required in the nano, um, if you're working with nanoparticles or nano composites, but that's usually not in a clean bench situation. That's usually moreover in, you know, you're filtering those composites out back into the lab space. In general, HEPA filters can provide up to, you know, an ISO one environment inside of a bench, especially when they're used inside clean rooms. So I hope that kind of helps a little bit with those, those differences. But ALPA filters will need change probably more frequently as well than HEPA filters. Okay, great. Thanks. Um, we might have time for one more here. Let's go to number 17. What causes the huge difference in operational upkeep costs between the A two versus a two with canopy? So that's gonna be your exhaust air, that's where your operational costs are coming from. Is that an A two is recirculating, recirculating air back into the laboratory space and a two with a canopy is connected to an exhaust so that all of that air is going outside the building. So your operational cost is really the air conditioned air that you have to put back into the lab space because of what your B S C is removing. You can kind of think about this in a way of like, if you're at home on a hot summer day and you just open your window, right? Or even in the winter, just open your window, you're letting all that either warm or cool air out of the building and then your heater or air conditioner has to work harder to replace that air. So that's what's generating that operational cost once you start to exhaust a cabinet. Okay. Great. Thanks very much. Sorry I didn't get to the, the mute button there, uh, Beth, but thanks very much for answering these questions. Again, we remind you to please take a look at the polls and let us know, um, more about any information you hope we cover in this webinar or that you would like to see in the future. And again, we do have a poll from Lab Manager for your chance to win an Amazon gift card. But that does bring us to the end of today's presentation. And again, I would like to remind you that all of the webinars from the Safety Digital Summit will be available for free on demand viewing within a few days. So please watch your email from a message from Lab Manager once these videos become available. Once again, thank you to our sponsors Lab, Conco Corporation, o House Corporation, ER Lab Inc, and Side Shield. Their support allows Lab Manager to keep these webinars free of charge for our readers. On behalf of Lab Manager, I'd like to thank Beth Dly for all the hard work she put into this presentation. And I'd like to thank all of you for taking time out of your busy schedules to Join us. Please be sure to tune into our next presentation at 2:00 PM Eastern today, OSHA considerations for Lab safety. For more information on all of our upcoming or on-demand webinars, or to learn more about the latest tools and technologies for the laboratory, please visit our website@labmanager.com. Thank you all for being part of our Safety Digital Summit, and we hope you have a great day.