Is fume hood noise bothering you? Are you thinking of calling your fume hood manufacturer for replacement? Try having your exhaust system checked first! 

A fume hood is essentially a box that contains the fumes generated during your chemical analysis. Without a proper blower, ducting and other exhaust ventilation system requirements, your hood cannot perform its function. In fact, 99% of ducted fume hood malfunction can be attributed to the exhaust ventilation system. 

Fume hood noise is not a simple matter to endure. This noise could already be a signal for compromised fume exhaustion. Are you willing to take the risk? 

Photo Courtesy of Esco

The "Shut the Sash" campaign above is courtesy of Esco, taken from their facebook account

Image courtesy of Esco Ducted Fume Hood

Today, more and more companies are transitioning their laboratories to a GREENER one. Why? Simply because of the idea of SAVING MORE and being green is more sustainable and practical. We are constantly pushing technology a notch higher for a more efficient devices, that's why we have LED TVs, smart washing machines, smart cars, LED bulbs and more.

Laboratories are touted to be huge energy spenders with consumption of about four times more energy than offices of the same size. One common culprit is your fume hood! There are systems for your fume hoods that you can implement in your laboratory to help reduce energy wastage. These systems shown below may be installed individually or in various combinations.

• Auto Sash Sensor
• Install an automatic fume hood closure system that uses motion sensors to assess whether a person is working in front of the hood or not. When no activity has been detected for a certain period of time, the hood's sash will be lowered automatically.

• Variable Air Volume (VAV) Fume Hoods
• This has been previously discussed (click here). I've differentiated the advantage of a VAV system over a CAV one. This type of hood is often combined with the auto sash sensor noted above and allows the fume hood to interface with the laboratory's HVAC system. As the sash is raised or lowered, the VAV controller will signal with the HVAC system to control the volume of air to be exhausted either thru the automatic adjustment of  the fan speed or position of the damper.

• High Performance Fume Hoods  

Esco Frontier Acela, a High Performance Fume Hood (Image courtesy of Esco Ducted Fume Hood)

• These re energy-efficient fume hoods capable of containing fumes at a reduced face velocity, hence, reduced exhaust volume. This directly translate more savings for the company.
  
  
  

Hey folks!

Admit it, buying a new fume hood is not an easy task. It requires lots and lots of research since it involves a huge amount of money. Just like buying a new car, you bid your time to get to know the product first before you give your big YES.

Listed below are the most commonly asked questions most buyers asked before they buy a new hood.








How definite are you that you really need a fume hood? There are different enclosures available and a lot of these looks similar but functionality wise, nah, they're different. I've already tackled this on a separate blog so you might want to check it out first, then come back here later.

Photo below will summarize. A fume hood only provides operator protection from hazardous and toxic chemicals. A laminar flow offers sample protection but not for the operator. Biosafety cabinets offer protection for both the user and the samples, however, it cannot function what a typical fume hood does!




If you're certain that you need a fume hood, then you have to identify whether you need a general purpose fume hood or a specialized one. For a more detailed discussion on the different hoods available, click this link. Enumerated below is a quick summary:

• General Purpose Fume Hood - used for applications that involves the ff: dilution, mixing of acids, slight (mild) evaporation, precipitation reaction, extraction, sample preparation, titration, filtration,e tc.
• Specialized Hoods
• Acid Digestion - for applications that involve using acids such as hydrcohloric, sulphuricm phosphoric and nitric.
• Perchloric Hood - if application involves using perchloric acid. Has a wash-down system to clean up the surface from any perchloric salts.
• Radioisotope hoods - for applications that involve radioactive materials such as alpha and beta particles
• Floor-mounted fume hood - provides comfortable space when users have to deal with large apparatus and hazardous containers

It pays to know. Again, be definite with what you need. It's surprising how many different fume hood exists, so you better be sure you select the right fume hood for your needs. If in doubt, reach out to your distributor or to a company's product expert/ specialist to confirm the right fume hood for your intended application.


Good question! First, what's the difference? A ducted fume hood requires complex ducting system to vent out air towards the atmosphere. Otherwise, a ductless hood recirculates air back to the laboratory, hence, no need for an expensive ducting system.

Having the liberty to choose between the two often causes confusion among laboratory planners. Worry not, listed below are important points to consider when choosing between a ductless or a ducted fume hood.

Important Points to Consider:

a.  Do you have an existing ducting system? If yes, then you might want to use a ducted fume hood. If outside ventilation is not possible, then go ductless!

b. Do you intend to heat solvents/ reagents/ acids inside the hood? If yes, then a ducted fume hood is more suitable. A ductless fume hood uses carbon filters to filter contaminated air. If force evaporation is involved, it will shorten the life of the carbon filter. Practicality wise, it's better to have a ducted hood.

c. Does your application involves using lots of chemicals? If yes, preferably a ducted fume hood is a better option. Carbon filters for ductless fume hoods are impregnated to absorb a specific group of chemicals only. Hence, choosing a ductless hood will only limit you to a list of chemicals approved by your distributor/ fume hood provider.

Depending on your budget, there's a list of features you would probably want your hood to have. Here's a few to name:

• Airflow Monitoring Device/ microprocessor controller - an airflow monitoring device provides an alarm if the hood's face velocity falls below the recommended range. It will also alarm if it goes higher than the set range. A too high face velocity causes air turbulence inside the hood and you wouldn't want that to happen since it would mean there's a tendency for contaminated air to leak out towards the operator.
• Worktop - choosing the wrong worktop spells disaster. A stainless steel worktop is suitable for perchloric acid applications but no longer the perfect choice if in addition to perchloric acid, if it would also entail the usage of both hydrochloric and nitric. 
• Auto-sash sensor/ motorized sash - with the cost of electricity not going down, what better way to save energy is to have a sensor that automatically closes the sash once it detects that nobody is working in front of the hood. 
• Circuit Protection Board - this serves to protect the fume hood unit whenever there are sudden fluctuation of current.

• Opening of a door
• A person walking by or if located near any pedestrian traffic routes, thoroughfares or walkways
• or placing near an air-conditioning unit

There are numerous other things you can add to your fume hood to ensure a safe and reliable performance. If you're using a ducted fume hood and if you're heavy on the use of acids, you might consider buying a wet scrubber. A scrubber works like a neutralizer -- it neutralizes the fume generated before it leaves the exhaust system. It helps save the environment and reduces air pollution.


If you are using a ductless fume hood, you might want to consider buying a Volatile Organic Compound (VOC) sensor. What it does is that it helps you monitor if your carbon filters are already scheduled to be change. Extra cost but it's worth the buck if it let you know this important information of knowing.

Fume hoods are literally huge energy spenders, with each one consuming more energy than three average homes in the US. You gotta watch this video which pretty summarizes how this problem can be addressed. Check it out!


Based on the video shown above, here are the hard facts:

• Estimated annual energy consumption for conventional fume hoods is around US$9,000 based on face velocity of 0.5 m/s (100 fpm) at full sash open position for 1.8 m (72”) hood. 
• The annual energy consumption of a conventional hood is equivalent to the consumption of around 3 average homes in the US.
•  A new line of high performance, low-flow fume hoods were engineered to help reduce energy consumption. These efficient hoods operate safely at a reduced face velocity of 0.3 m/s
• With the reduced face velocity, energy consumption can also be reduced dramatically . 
• In using a high performance hood, it is estimated for the exhaust volume to be reduced by 58%. This translates to an annual savings of US$ 5,600.

Hi folks,

I've been receiving some feedbacks about people using the wrong cabinet for their application. I was horrified when i found out that someone did an acid digestion inside a Biosafety cabinet and another doing a microbial analysis inside a laminar flow. Imagine the risk of exposure the operator is putting to himself, more so to the people working around as well. Ignorance in the lab is unforgivable if it means putting anyone's life in jeopardy.

If you are part of the team on the procurement and designing (or retrofitting) of your laboratory, it is also your job to decide whether the fume hood you're planning to install should have a Constant Air Volume (CAV) or a Variable Air Volume (VAV). Why do we think it's important? An average fume hood exhausts around 750 to 1,000 cubic feet per minute of conditioned air, hence, imagine the amount of load it's putting on the lab's HVAC system. If not well planned, this will negatively impact the operating costs of the laboratory.

Don't be overwhelmed by these terminologies as these "jargons" will be thoroughly explained with photos I personally created.

The "Shut the Sash" campaign above is courtesy of Esco, taken from their facebook account.

I saw this post from Esco Fume Hood's facebook account and it pretty much summarizes what i want to tell you about choosing the right fume hood for your intended application. As you see, there are a multitude of things we can do with our fume hood but that doesn't mean we can just use any fume hood for any chemical analysis you desire. We also need to do the match-making game, ensuring that we perform the analysis inside the right fume hood or else it might end up you compromising your own or everyone's safety. Again, photos are not mine and were lifted from Esco Fume Hood's facebook account.

We all want to work safely in the lab, right? The best way to avoid accidents and bad exposure to noxious chemicals is to know the proper way of using and handling your fume hood. The level of protection provided by this equipment is affected by the manner in which the fume hood is used. No fume hood, however well designed, can provide adequate containment unless good laboratory practices are used. Here are some pointers on how to work safely and efficiently: