What is the Advantage and Disadvantage of Chemistry Fume Hood

Businesses use laboratories in a multitude of ways these days. And, with tight budgets, limited square footage, changing business dynamics and safety considerations involved, businesses sometimes struggle when it comes to purchasing lab furniture.

If you want to learn more, please visit our website.

One important decision comes when it’s time to purchase a chemical fume hood for your new laboratory or during a redesign.

And, let’s be honest, the stakes can be high. Just check out this article about a tragic laboratory accident at UCLA to see the potential consequences of working in a fume hood.

Here we look at your options...a ducted fume hood or a ductless fume hood?

The Standard – Ducted Fume Hood

Ducted fume hoods have ventilated enclosures, operate within the framework of your building infrastructure and pull contaminants out of your building through the HVAC system. 

Ducted fume hoods have a base, work surface, hood, blower and ducting that carries the air outside of the building. The engineer of the heating, ventilation and air-conditioning (HVAC) system needs to determine if your room has enough air to provide the necessary volume of ventilation to the hood.

The maintenance of the fume hood is performed as part of the building's maintenance, and is generally performed by those in charge of the mechanical systems. Typically, the Maintenance or Environmental Health and Safety team take care of any issues.

Your HVAC engineer can work with your team to provide optimal air supply and balance, so that everything functions properly within the fume hood.

Ducted fume hoods are considered safest for workers in laboratories, and its often the easiest for employers to maintain. Many universities ONLY allow ducted fume hoods in their facilities to maintain worker and student safety.

Advantages and Disadvantages of Ducted Fume Hoods

Advantages Disadvantages Safer for lab workers More expensive Can handle a wide range of chemicals More difficult to install Easy to operate and maintain Stationary in the lab Exhaust system keeps contamination outside lab More difficult to move or relocate Uses more energy

The Alternative – Ductless Fume Hoods

Ductless fume hoods operate off a carbon filter system that recirculates filtered air into your building. Ductless hoods are often referred to as re-circulating range hoods.  They filter the air and then return the clean air back into the workspace.  They are self-contained filtered laboratory enclosures. Their primary features are mobility, they save energy, are easy to install and cheaper because no ductwork is required.

The disadvantage is that workers are at a greater risk of chemical exposure, filter maintenance is required, they can be noisy due to the internal blower and there are limited applications for filter options.

Ductless fume hoods are ideal for labs that require mobility, handle light to moderate chemical loads and are looking for a cost-effective option from both an installation and operational perspective.

Advantages and Disadvantages of Ductless Fume Hoods

Advantages Disadvantages Less expensive Handles Limited chemicals Easy to install Need to replace filters  Mobile in the lab Not as effective at removing chemical fumes Easily moved or relocated Not for constant use Use less energy

Is A Ducted Fume Hood or Ductless Best for My Laboratory ?

So, how do you determine which is the right fume hood for your laboratory...ducted or ductless?

Here are some questions to ask yourself:

    1. Do you work with more than 10 different chemicals?
    2. Are you working with small or large volumes of chemicals?
    3. Does your lab have a high volume of inexperienced people working with chemicals, such as a university lab?
    4. Does your building have an HVAC system and a team to manage it?
    5. Is mobility necessary for your operation?
   6. Do you have techs that can properly maintain a system, e.g. changing out filters?
   7. Will the chemicals you are using adequately filter through carbon?

Answering these questions about how you work with chemicals in your lab will help you determine the appropriate application for your needs.

Laboratory safety and workload should be the primary deciding factors in your decision. In a ductless fume hood, there should be no extreme heating, no more than 10 chemicals should be used per application, small volumes of chemicals should be used (approximately 500 mls or less) and exposure time should be within 2-3 hours per day. 

There are a range of filters that have different chemical trapping capacities, but if your application doesn’t match available filters you’ll be required to move forward with a ducted fume hood. Talk to your fume hood provider about the various filters for chemical groups.

Lastly, determine how often you will be replacing your carbon filter, this will also give you a more accurate financial cost. Keep in mind that the filter life depends on the chemicals used, evaporation rate, chemical volume, duration of usage and the temperature of the chemicals.

Fume Hood Safety Considerations

Regardless of which type fume hood you choose, safety is always important. Fume hoods, when used properly, help protect lab employees and students working with toxic or volatile chemicals and compounds.

The fume hood serves as a physical barrier between the employee and the harmful fumes, fires, explosions and spills that might result from handling or experimentation. Because of this, fume hood safety is extremely important and can help protect your employees and student workers from injury.

Even though fume hoods are designed to protect against unexpected reactions of volatile chemicals, laboratory workers must serve as the first line of defense against. The equipment can only perform and protect if used properly. 

Learn more about safety in our article, A Fume Hood Safety Checklist For Everyday Use.

Summary

It is important to make sure that you have the right fume hood for your lab application, because the safety of your work and your employees is at stake.

It is always best to consult with an expert fume hood manufacturer, so that your lab does not go up in smoke!

Fume Hoods Play a Critical Role in Preventing Exposure to Chemicals, Particulates, and Other Risks in Laboratory Research and Product Manufacturing

If you are designing or upgrading a laboratory facility, providing a safe, secure place for your laboratory research team is a top concern. State-of-the-art fume hoods, — if designed properly and used sensibly —  can protect workers by significantly reducing unnecessary exposure to toxic chemicals and radioactive materials. They can also help prevent particulate contamination in clean room environments.

Fume Hood Designs Vary Significantly Based on the Type of Hazardous Substance Used

It would be easy if there were a universal fume hood design that could handle any type of hazardous substance that you threw at it — unfortunately, that’s not the case.

That’s because fume hood designs are closely related to the specific types of hazardous substances that they can handle. This makes it especially important to set down some parameters during the design stage to identify which classes of materials that your lab can or cannot handle — now and in the future.

Comparison of Ductless Fume Hood Designs versus Laminar Flow Hoods

Traditional laminar flow fume hoods have ducting that vents the air from the hood area to outside vertical stacks. Depending on the compounds being used, it may be further filtered and/or treated. The exhaust is then dispersed, in very low concentrations, into the atmosphere.

The laminar flow approach has some disadvantages:

First, laminar flow fume hoods remove a large amount of air from the laboratory, which must be replaced by new temperature controlled air supplied by the HVAC system. This can be expensive from an energy use perspective – these types of fume hoods have been known to drive your electricity bills through the roof.

Second, it’s not possible to move laminar flow hoods around to different locations easily. They are tied to extensive ductwork systems — and typically filtration and treatment systems as well — laminar flow hoods cannot be moved without extensive renovations. Foresight and planning ahead are paramount in the design stage.

Ductless fume hoods are a primary alternative option.

In this type of fume hood, the air is treated within the unit using extensive filtering systems — typically incorporating some form of activated charcoal filtration. The treated air is then returned to the laboratory. This ductless design overcomes the two main objections of laminar flow hoods: Because the air is returned, there is less drain on the HVAC system for a lower energy cost, and ductless systems can be moved around within a laboratory relatively easily as they are not dependent on ducts mounted through the walls. They also typically plug into standard 110 or 220-volt outlet boxes. Placed on top of a Formaspace Basix with casters, the move is further simplified.

However, ductless systems have their own set of disadvantages:

Ductless systems can only be used when the chemicals passed through it are known quantities and are approved for use with the filtration system. For example, ammonia and carbon monoxide gasses will easily pass through a standard activated carbon filter. This means that each and every chemical compound that could be used in a ductless system needs to be certified to match the filtration capabilities of the system you use. Because of these limitations, ductless systems are excluded for use in experiments or processes which could produce unknown results which could evade treatment by the type of ductless filtration system in use.

There are other disadvantages as well. Ductless fume hoods require the use of expensive filters that must be replaced at regular intervals — if this is not done correctly, it will pose a significant risk to lab personnel. Noise is also another potential disadvantage — since the filtration fan unit is built into the unit.

Comparison of Advantages and Disadvantages of
Ductless Fume Hoods versus Laminar Flow Fume Hoods

Ductless Fume Hoods

Advantages:

Disadvantages:

Not attached to fixed ductwork Only specific chemicals and processes can be used Less energy cost Not suitable for experiments with unknown outcomes Easily moved around lab Loud fan noises Contaminated air is contained in filter system Risk to personnel if filtration system not maintained

Laminar Flow Fume Hoods

Advantages:

Disadvantages:

More suitable for use in experiments with unknown outcomes Requires extensive ductwork installation Can be used with a wider range of compounds and processes Uses significant amount of energy (HVAC) to replace treated air Less risk of contamination inside the building Generally, fumes are ducted to the atmosphere rather than treated Typically less noisy than self-contained ductless systems Difficult to reconfigure laboratory to a new floor plan without extensive work

Formaspace Can Provide You with an Unlimited Range of Specialty Fume Hood Designs for Your Unique Application

In addition to the general purpose laminar flow and ductless fume hoods discussed above, Formaspace can also provide specialty fume hood designs that handle specific types of materials or processes.

Low-Bench Fume Hoods

Many Formaspace customers looking for a general fume extraction solution choose the so-called Low-Bench design. Because it sits directly on a low height Formaspace workbench (18” off the ground), it’s easy to coordinate this fume hood with other matching design elements, such as Formaspace work tables, storage units, wet sinks, and more.

Perchloric Acid Fume Hoods

Working with Perchloric acid can result in a dangerous residue build-up of perchloric acid crystals, which are an explosion risk. Fume hoods designed for this application have built-in washing systems to eliminate the risk.

Goto E3 Green Technology to know more.

Acid Digestion Fume Hoods

High acid concentrations can damage work surfaces in the fume hood; using Polypropylene or PTFE (Teflon) coated surfaces will resist the acid. It may also be necessary to replace the traditional glass material in the fume hood door (called the sash) with transparent material made of polycarbonate, which resists acid etching more effectively than glass.

Internal Wash Fume Hoods

Like Perchloric acid fume hoods, other chemical compounds can build up on the inside of surfaces. Fume hoods with built-in wash systems can clean the internal surfaces to prevent damage caused by the accumulation of chemical compounds.

Scrubber Fume Hoods

The exhaust waste from many chemical substances can be treated via an ionizing scrubbing system. The exhaust air is passed through a series of filter elements which chemically bind to the chemicals, trapping it so that it can be disposed of as solid waste.

Radioisotope Fume Hoods

If you are working with radioactive compounds, then you need a fume hood with built-in protection from radiation — typically in the form of heavy lead bricks lining the walls — that is encased in a protective stainless steel case.

Need to Speak with an Expert on Fume Hood Applications? Call Formaspace.

Do you have questions about specialty fume hood designs that handle specific types of materials or processes? Want to order a fume hood for your unique application?

Visit the fume hood section of our website to learn more.

Then talk to our experts.

Our Formaspace Design consultants will recommend the exact type of fume hood you need for your laboratory or manufacturing facility.

Fume Hoods Play a Critical Role in Preventing Exposure to Chemicals, Particulates, and Other Risks in Laboratory Research and Product Manufacturing

If you are designing or upgrading a laboratory facility, providing a safe, secure place for your laboratory research team is a top concern. State-of-the-art fume hoods, — if designed properly and used sensibly —  can protect workers by significantly reducing unnecessary exposure to toxic chemicals and radioactive materials. They can also help prevent particulate contamination in clean room environments.

Fume Hood Designs Vary Significantly Based on the Type of Hazardous Substance Used

It would be easy if there were a universal fume hood design that could handle any type of hazardous substance that you threw at it — unfortunately, that’s not the case.

That’s because fume hood designs are closely related to the specific types of hazardous substances that they can handle. This makes it especially important to set down some parameters during the design stage to identify which classes of materials that your lab can or cannot handle — now and in the future.

Comparison of Ductless Fume Hood Designs versus Laminar Flow Hoods

Traditional laminar flow fume hoods have ducting that vents the air from the hood area to outside vertical stacks. Depending on the compounds being used, it may be further filtered and/or treated. The exhaust is then dispersed, in very low concentrations, into the atmosphere.

The laminar flow approach has some disadvantages:

First, laminar flow fume hoods remove a large amount of air from the laboratory, which must be replaced by new temperature controlled air supplied by the HVAC system. This can be expensive from an energy use perspective – these types of fume hoods have been known to drive your electricity bills through the roof.

Second, it’s not possible to move laminar flow hoods around to different locations easily. They are tied to extensive ductwork systems — and typically filtration and treatment systems as well — laminar flow hoods cannot be moved without extensive renovations. Foresight and planning ahead are paramount in the design stage.

Ductless fume hoods are a primary alternative option.

In this type of fume hood, the air is treated within the unit using extensive filtering systems — typically incorporating some form of activated charcoal filtration. The treated air is then returned to the laboratory. This ductless design overcomes the two main objections of laminar flow hoods: Because the air is returned, there is less drain on the HVAC system for a lower energy cost, and ductless systems can be moved around within a laboratory relatively easily as they are not dependent on ducts mounted through the walls. They also typically plug into standard 110 or 220-volt outlet boxes. Placed on top of a Formaspace Basix with casters, the move is further simplified.

However, ductless systems have their own set of disadvantages:

Ductless systems can only be used when the chemicals passed through it are known quantities and are approved for use with the filtration system. For example, ammonia and carbon monoxide gasses will easily pass through a standard activated carbon filter. This means that each and every chemical compound that could be used in a ductless system needs to be certified to match the filtration capabilities of the system you use. Because of these limitations, ductless systems are excluded for use in experiments or processes which could produce unknown results which could evade treatment by the type of ductless filtration system in use.

There are other disadvantages as well. Ductless fume hoods require the use of expensive filters that must be replaced at regular intervals — if this is not done correctly, it will pose a significant risk to lab personnel. Noise is also another potential disadvantage — since the filtration fan unit is built into the unit.

Comparison of Advantages and Disadvantages of
Ductless Fume Hoods versus Laminar Flow Fume Hoods

Ductless Fume Hoods

Advantages:

Disadvantages:

Not attached to fixed ductwork Only specific chemicals and processes can be used Less energy cost Not suitable for experiments with unknown outcomes Easily moved around lab Loud fan noises Contaminated air is contained in filter system Risk to personnel if filtration system not maintained

Laminar Flow Fume Hoods

Advantages:

Disadvantages:

More suitable for use in experiments with unknown outcomes Requires extensive ductwork installation Can be used with a wider range of compounds and processes Uses significant amount of energy (HVAC) to replace treated air Less risk of contamination inside the building Generally, fumes are ducted to the atmosphere rather than treated Typically less noisy than self-contained ductless systems Difficult to reconfigure laboratory to a new floor plan without extensive work

Formaspace Can Provide You with an Unlimited Range of Specialty Fume Hood Designs for Your Unique Application

In addition to the general purpose laminar flow and ductless fume hoods discussed above, Formaspace can also provide specialty fume hood designs that handle specific types of materials or processes.

Low-Bench Fume Hoods

Many Formaspace customers looking for a general fume extraction solution choose the so-called Low-Bench design. Because it sits directly on a low height Formaspace workbench (18” off the ground), it’s easy to coordinate this fume hood with other matching design elements, such as Formaspace work tables, storage units, wet sinks, and more.

Perchloric Acid Fume Hoods

Working with Perchloric acid can result in a dangerous residue build-up of perchloric acid crystals, which are an explosion risk. Fume hoods designed for this application have built-in washing systems to eliminate the risk.

Acid Digestion Fume Hoods

High acid concentrations can damage work surfaces in the fume hood; using Polypropylene or PTFE (Teflon) coated surfaces will resist the acid. It may also be necessary to replace the traditional glass material in the fume hood door (called the sash) with transparent material made of polycarbonate, which resists acid etching more effectively than glass.

Internal Wash Fume Hoods

Like Perchloric acid fume hoods, other chemical compounds can build up on the inside of surfaces. Fume hoods with built-in wash systems can clean the internal surfaces to prevent damage caused by the accumulation of chemical compounds.

Scrubber Fume Hoods

The exhaust waste from many chemical substances can be treated via an ionizing scrubbing system. The exhaust air is passed through a series of filter elements which chemically bind to the chemicals, trapping it so that it can be disposed of as solid waste.

Radioisotope Fume Hoods

If you are working with radioactive compounds, then you need a fume hood with built-in protection from radiation — typically in the form of heavy lead bricks lining the walls — that is encased in a protective stainless steel case.

Need to Speak with an Expert on Fume Hood Applications? Call Formaspace.

Do you have questions about specialty fume hood designs that handle specific types of materials or processes? Want to order a fume hood for your unique application?

Visit the fume hood section of our website to learn more.

Then talk to our experts.

Our Formaspace Design consultants will recommend the exact type of fume hood you need for your laboratory or manufacturing facility.

The company is the world’s best Chemistry Fume Hood supplier. We are your one-stop shop for all needs. Our staff are highly-specialized and will help you find the product you need.