Fume Hood Performance Testing

When you purchase a fume hood, the number one purpose you have in mind is to protect yourself. How can you be sure that the hood you purchase will be able to serve your needs and keep fumes where they belong?

In this day and age, we tend to assume that the products we buy and use are carefully tested and inspected before they come into our possession. We especially tend to believe this when the product is expensive and is related to our safety. Unfortunately, some fume hood manufacturers choose to skip these steps and leave testing up to the individuals and facilities purchasing their products. This is really unfortunate because most fume hood owners may not realize the complexity behind fully testing a fume hood and may not be able to carry out testing properly on their own.

Manufacturers like AirClean Systems take care of testing on the front end, ensuring that our hoods meet and in some cases exceed standards set by ASHRAE, SEFA, OSHA, and others. Knowing that each ductless hood has already been intensely tested and scrutinized prior to shipment, allows our customers to work confidently when using our products.

So what does testing look like and what does it mean for you when you're looking to purchase a new hood?

To start, a fume hood is supposed to contain and manage vapors and gases; the best fume hood will prevent any of these from escaping. In order to determine whether a fume hood is good or not, it must undergo a series of rigorous tests to see if it offers adequate protection.

The main testing methodology is laid out by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) in ANSI/ASHRAE STANDARD 110-2016 - Methods of Testing Performance of Laboratory Fume Hoods. ASHRAE has been hard at work since its founding in 1894, trying to advance, "human well-being through sustainable technology for the built environment." ASHRAE 110-2016 outlines the required procedure to evaluate containment by fume hoods, "including tests to visualize the flow of fumes, detect low concentrations of tracer gas, and determine the gas that can escape from the hood sash."

The purpose of the airflow visualization test, "is to visualize the hood's ability to contain vapors and render an observation of hood performance." Smoke is released from within the enclosure enabling an inspector to see airflow patterns. This qualitative test shows how airflow patterns within the hood's enclosure, whether fumes are escaping from the hood, and how turbulence at the hood's face affects any escaping fumes. When designing a fume hood, special care must be taken to avoid eddy currents or areas that might cause a swirling motion that can lead to the buildup of fumes and concentrated vapors. Whether ductless or total exhaust, our units provide AirZone baffling which helps pull air evenly throughout the ductless hood to help minimize these dead zones or eddy currents.

The face velocity test measures the average velocity of the air at the hood's face, or opening, while the fume hood is in operation. It also measures cross drafts and helps to calibrate airflow monitors. Every total exhaust or ductless fume hood AirClean Systems manufactures is quality control tested (QC) prior to it leaving our facility. Every ductless hood includes a built-in airflow sensor to monitor the face velocity and ensure it is functioning properly. For ductless units, the airflow is automatically adjusted to maintain a user-defined face velocity. With proper containment relying on steady airflow, these built-in safety features add another tool to ensure your unit is functioning properly.

The gas containment test is used to quantitatively measure a fume hood's containment ability. A mannequin is placed where the fume hood operator might normally stand and has a device attached to record the presence of harmful chemicals in the air. Gas is then released into the hood and the mannequin's detection device reports how the hood performed with regards to containment.

When taken together, these tests give a clear look into a fume hood's performance and reliability when dealing with potentially harmful substances. They also aim to address and provide proof of performance as manufactured, as installed, and as operated.

Not all fume hoods on the market are ASHRAE certified. Many manufacturers leave testing up to the consumer. At AirClean Systems, every product is tested in-house to meet or exceed applicable safety standards and regulations. Our products are also tested by an unbiased third party to ensure our products meet the highest standards. Stringent QA/QC procedures are carried out during all phases of production, guaranteeing the highest quality and reliability of each ductless hood, workstation, and enclosure. And because all our units are shipped fully assembled, consumers never have to question whether a fume hood will be accurately assembled upon receipt.

Call today to speak with one of our sales professionals about a fume hood that will suit your needs and give you peace of mind knowing it has been tested, tested, and retested to ensure your safety and the success of your application.