ASHRAE 52.2 is a method of testing general ventilation air cleaning devices to determine their removal efficiency as a function of particle size. It i
s a method that determines the ability of an air filter to remove particles on the basis of specific particle sizes ranging between 0.3 to 10 microns. A central feature of ASHRAE 52.2 is the incorporation of the Minimum Efficient Reporting Value (MERV) for each filter tested. Angela Southey is the head of the environmental test chamber at airmid healthgroup. In this interview, we ask Angela about Airmid’s new ASHRAE 52.2 test duct, its functional association with the Environmental Test Chamber and the importance this facility has for HVAC testing, MERV testing and its potential for contract research.
This article has been written in Q and A format following an interview with Angela Southey PhD
Tell us about the ASHRAE 52.2 type test duct attached to the Environmental Test Chamber
The ASHRAE rig is built from aluminium and it has a smooth surface which is suitable for the introduction of microorganisms, as it can be easily cleaned down afterwards. The test rig flows from the back of the chamber to the front of the chamber and it has a large variable-speed fan at the back of the chamber which can be adjusted according to our experimental requirements. The fan speed can go from 0.5 to 4 m3/sec.
Describe the access ports and panels
On the test duct, there are a number of doors at the sides which are sealed with gaskets. These can be removed to enable sample collection systems to be put in and also enable cleaning down the duct after testing. We can also attach air cleaning devices in to the duct. For example we are currently testing a UV disinfection device using this facility.
What is novel about the system set up of the test ducting?
What is novel about this test duct is that it is connected to our environmental test chamber. The chamber and duct can be worked independently of each other or together. This is very useful for our aerobiology research that we are doing here at the moment. It allows us to examine how microorganisms will behave in the test duct in conjunction with an air-cleaning device. It also lets us monitor what happens in the test chamber. This allows us to ask questions such as do the microorganisms pass into the chamber and how are killed by the disinfection system in the test duct?
What manufacturers would benefit from access to this facility?
I believe there are a number of industries that would find this facility of value to the testing of their products. Industries that would benefit from such testing may include air-cleaner companies who could test an air-cleaner in the duct or they could also test an air-cleaner in the chamber and look at the effect in the duct. MERV testing for filters can also be carried out in this facility given it is an ASHRAE 52.2 test rig. We can also look at disinfection systems within the duct such as UV disinfection, as well as other types of photocatalytic oxidation systems which have carbon filters and used for breaking down VOC’s. We can also measure these VOC’s in the duct as well as look at allergen removal by carbon filters.
What kind of claim verification can this system offer a prospective customer?
This test rig can be used for a number of claim verifications. We can look at the percent inactivation efficiency of UV disinfection in the test rig. This is calculated based on the number of microorganisms introduced at the proximal end as they pass by the UV light and are killed off, and then what ends up at the distal end. Also, it is possible to look at MERV testing for filters to see how efficient the filters are at trapping microorganisms and dust. In addition to proximal and distal studies in the duct, you can also determine what ends up in the chamber; so, if you pass by an air-cleaning system, do the microorganisms get carried into the room. This can tell you how efficient the air-cleaner is at removing those particles, not just in the duct but also in the chamber.
What other groups would find data from this system of value?
I think this would be particularly important for industries that are targeting hospitals, nursing homes and large office complexes, as well as department stores for controlling microorganisms circulating in their HVAC duct systems. I think such companies would definitely get ahead of the market if they are able to say that their HVAC system does not circulate microorganisms or allergenic particulates and works in the rooms that are connected to it.
How is the facility integrated into the other airmid analytical capabilities?
This facility is uniquely positioned in a hub of laboratories, run by a range of scientists with advanced levels of training. Samples coming from the test chamber and duct can go directly into our in-house testing laboratories where samples many be analysed. At Airmid, we have a mycology lab, virology lab, bacteriology lab and an allergen testing lab. So, any of those can be tested in this facility here and then analysed in the lab.
Further information on airmid‘s test chambers
Watch a video of the interview
About airmid healthgroup
airmid helps their clients across a number of sectors improve, add value and differentiate their customer offerings through a focus on bio-medical data, health impact claims and optimising indoor air quality. We have a uniquely integrated facility which combines standard microbiology testing, molecular biology and state-of-the-art air sampling with a highly developed climate controlled walk in environmental test chamber. This gives us a world class aerobiology research facility that allows us to follow airborne pathogens such as nominated viruses, bacteria, molds or other ultra-fine particles. As a world’s leading bio-medical research facility our clients describe us as a specialised extension to their research capabilities, we capture, store and manage data and most importantly convert it into tangible market value.
About Angela Southey
Head of Virology & Environmental Testing Chambers
Angela has responsibility for the running of our Virology Laboratory and Environmental Testing Chambers. Angela qualified with a BSc. in Microbiology from UCC, before going on to complete a PhD in Lung Fibrosis in UCD. She then spent two years working in Japan on Ulcerative Colitis with Tanabe Seiyaku Ltd. Returning to Ireland she took up a senior research position in the Veterinary College, UCD followed by extensive industry experience in the diagnostic area with Wyeth Biopharma and Abbott Diagnostics.