HEPA Vacuum - Guide to Selecting a Top Quality HEPA Vacuum

HEPA Vacuum History

The need for absolute filtration arose during World War II and was developed by the Atomic Energy Commission as part of the Manhattan Project to produce the first atomic bomb. There was a pressing need to address the health and safety issues raised by radioactive dust handling. Research and development produced the first HEPA (High-Efficiency Particulate Air) filters for the ventilation systems used to deliver ultra-clean air to clean rooms.

Certification of filtration

A filter to be certified HEPA must be tested and proven to filter particles as small as 0.3 microns to 99.97% efficiency at its designed airflow. To understand what this type of filter does, it helps to understand what a micron is. A micron is 1 millionth of a meter. A human hair is approximately 100 microns wide. Particles smaller than 10 microns are not visible to the human eye—a particle of tobacco smoke averages 0.01 to 1 micron. Most bacteria range from 0.35 to 10 microns. However, almost all viruses are smaller than 0.03 microns, and HEPA filters are not effective at trapping them.

Features of a High Quality HEPA Vacuum

Not all HEPA vacuums are of equal quality. Here are some guidelines to follow to help get the best quality vacuum for the price. Much of this applies to getting good value in a vacuum generally. Starting from the ground up, look for high-quality ball bearing wheels and casters of sufficient size to be easily moved over irregular floors and up and downstairs. Next, examine the construction of the collection devices for ease of cleaning and disposal of contaminants. Look for smooth, easily wiped surfaces like stainless steel and aluminum. Plastic surfaces should be smooth and free of texture.

High-Quality HEPA Vacuums use Bypass Motors

Next, examine the power source – the motors. Better quality electric vacuums utilize bypass motors. Lesser quality vacuums use flow-through motors. Here’s the difference; a bypass motor is made, so the motor chamber is isolated from the impeller chamber. The impeller is the fan that creates the lift and suction that the vacuum produces. The motor chamber has its own cooling fan that uses clean air from outside the vacuum head to keep the motor and its carbon brushes cool. A flow-through motor uses the airflow generated by the impeller to cool the motor. In a flow-through motor, any particles that escape the filter media are actually blown into the motor chamber, reducing the motor's life.

Multiple Layers Pre-Filtration

Finally, check the prefilters used on the vacuum. There should be multiple prefiltration layers to remove as much contaminant as possible before they reach the HEPA filter. Effective prefilters extend the life of the HEPA filter and help reduce operating costs. Good quality HEPA vacuums utilize three and even four prefilters in some cases.

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Common Applications

HEPA filtration for cleanroom applications soon found its way into other industries such as microelectronics, pharmaceuticals, chemicals, and the nuclear power industries. Soon other uses were realized for this technology – central and portable vacuum cleaners.

One of the earliest successful uses was their deployment in the asbestos abatement industry from the late 1950s to the present day. Portable HEPA vacuums also proved useful for asbestos brake removal at auto repair shops.

Next came lead paint abatement projects in public housing and government buildings. New York City recognized the dangers of improper lead paint abatement practices and the hazard of lead paint poisoning to children. It passed a law regulating abatement in public buildings. The following comes from the City Council of the City of New York:

The Council finds that lead poisoning from paint-containing lead is a preventable childhood disease and a public health crisis. The Council further finds that the hazard in dwellings from paint containing lead is subject to many factors, such as building age and maintenance level. The council also finds and declares that the City government must focus on primary prevention as the essential tool to combat childhood lead poisoning and prevent children from suffering the adverse health and other effects of exposure to lead-based paint. The pursuit of primary prevention, which means eliminating lead hazards before children are exposed, has been recommended by the United States Centers for Disease Control and Prevention and promoted by leading experts in the field as a critical course of action to protect young children's health. The Council, therefore, declares that resources must be directed to primary prevention, including identifying children who are most at risk.

So begins the New York City Childhood Lead Poisoning Prevention Act of 2003, which finally rests the 20-plus year debate over lead paint abatement versus lead paint containment. The new law stands solidly on the side of abatement and makes owners of most multi-dwelling buildings responsible for identifying dwellings where children under the age of seven live. It also holds owners responsible for inspecting dwellings with young children and public areas to promptly determine if a lead paint hazard exists and promptly remove the lead paint. Building owners are required to check their buildings annually for apartments with children under seven. It is currently estimated that 35,000 New York City children have elevated lead levels in their blood. Each year at least 4,000 new lead poisoning victims are identified in New York City. Building owners that fail to comply with the law face fines and possible incarceration. The new law also applies to most daycare facilities in the city.

Even as recently as 2018, the issue with lead in paint continues in New York City and other areas. Continued focus on this issue is required by law. 

The recommended method for lead paint abatement calls for sealing the work area and the wet scraping method of removal. On completion of the scraping, all surfaces must be HEPA-vacuumed or washed with detergent before repainting.

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HEPA Vacuums Today

Today, these vacuums are employed in a wide variety of industries to address the safety and health of workers and residents in any environment where the inhalation of microscopic particles can pose a health risk. One of the most widespread uses of HEPA vacuums today is in the duct cleaning service industry, where the recovery of mold spores and other dangerous particles is critical. See for more HEPA vacuum uses.

The National Air Duct Cleaners Association (NADCA) has been developing standards to regulate the proper cleaning of ventilation systems. In their document entitled “NADCA General Specifications for the Cleaning of Commercial Heating, Ventilating and Air Conditioning Systems,” NADCA states, “Particulate Collection: Where the Particulate Collection Equipment is exhausting inside the building, HEPA filtration with 99.97% collection efficiency for 0.3-micron size (or greater) particles shall be used.” Currently, NADCA is working on a draft for a standard requiring scheduled recertification of HEPA vacuums used for a ventilation system cleaning by contractors. It’s easy to see how NADCA takes the health risks of exposure to contaminants seriously.

HEPA filter vacuums have proven invaluable for persons suffering from allergies, asthma, and other respiratory illnesses. Conventional vacuums pick up dust, dander, pollen, and whatever else is in or on the surface being cleaned and discharge the finer particles back into the air stream where the inhabitants can breathe them. HEPA vacuums recover and trap small particles, so they are permanently removed from the environment.

The filters are certified to capture particles 0.3 microns in size is that it is the particle size that mechanical filters are least efficient at collecting. Particles measuring 0.3 microns in size are the most difficult to remove from the air and can easily get deep into the respiration system, where they can cause or aggravate lung problems.

HEPA filters are so efficient that only 3 out of every 10,000 particles that enter the filter will get through. Interestingly enough, these filters actually become more efficient with age as the trapped particles make the air passages in the filter even smaller and more difficult for particles to navigate.

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Industrial quality Vacuums

Industrial HEPA vacuums are a critical element of any comprehensive cleaning and maintenance program for industries ranging from food production to biotechnology. Industrial HEPA vacuums serve several purposes in these environments, including improving indoor air quality (IAQ), removing debris, and controlling harmful contaminants' build-up. These vacuums ensure that harmful particles are not released back into the air to be breathed in by employees or to taint research or production results through their unique filtration abilities.

Industrial HEPA Vacuums and Sick Building Syndrome

These vacuums can dramatically reduce the biological and chemical pollutants that contribute to what is known as "sick building syndrome." This causes a building's inhabitants to feel sick when they are in the building. Such contaminants cause biological pollution as toxic black mold, viruses and bacteria, dust mites, pollen, and insect body parts. To avoid sick building syndrome, comprehensive cleaning maintenance programs must be followed, including using an industrial HEPA vacuum cleaner.

Industrial HEPA vacuums play a large part in mold prevention and remediation because they trap 99.7% of all mold and bacteria. Mold has a huge negative impact on humans' health and on the buildings, they work in. According to the Environmental Protection Agency, mold can cause eye irritation, nasal stuffiness, skin irritation, and even fever or breathing problems. Sick building syndrome sufferers may even contract infections and even toxicosis.

Commercial HEPA Vacuums

Commercial HEPA vacuums dramatically reduce dust and dirt in a building's interior by trapping small particles like mold and dust. Goodway Electric-Powered Dry HEPA Vacuum Because clean environments have a positive physical and psychological impact, it is recommended that a commercial HEPA vacuum be used in cleaning surfaces likely to be encountered by employees and customers. This will improve the building's sanitation and minimize the risk of airborne particles and their related symptoms.

Commercial HEPA vacuums are also an important element in keeping air ducts free of dust and debris. Because the vacuum reduces the number of particles in the air, the air ducts become blocked much less often.

Commercial HEPA Vacuums Control Bacteria, Fungus, and Parasites

Commercial HEPA Vacuums are often used to clean buildings susceptible to contaminants like those that accompany rodent and pest infestation. A build-up of fecal matter, and the bacteria, fungus, and parasites that accompany it, can cause serious harm to employees and customers. These infestations can also harm a building's machinery, materials, and reputation. HEPA vacuums are the only vacuum cleaners recommended as part of the remediation of infestation as they minimize the occurrence of these hazardous particles in the air.

Goodway HEPA vacuums have been proving themselves in difficult environments ranging from nuclear power plants to laboratory clean rooms to pharmaceutical companies where processing equipment must be completely cleaned between product batches.

Cross-contamination is a real issue for many companies involved in the production of consumable goods. HEPA vacuums are a necessity in production environments where cleanliness is a must. Businesses that don't take necessary precautions to stabilize the environment in which their product is created often face negative consequences, including the financial fallout and negative reputation that results from product recalls.

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HEPA Vacuum Performance Ratings

When comparing vacuums, two performance ratings should be evaluated – static lift and air displacement. Many buyers make the mistake of comparing horsepower or wattage when shopping for a good vacuum. The motor's speed, the number of motors, and the impeller's design have more to do with the performance of a vacuum than horsepower or wattage. Some vacuums are designed to produce high static lift - the machine's ability to get heavier materials like liquids or metals in motion. Static lift is measured in inches of water or mercury. Others are designed to displace large amounts of air, measured in cubic feet per minute (CFM). These machines are best for the recovery of light particles such as bacteria, pharmaceutical dust, lead paint sanding dust, asbestos fibers, and so on. Electric vacuums are usually designed for either high lift or high flow. Pneumatically powered vacuums, however, can be made to produce a high level of both performance characteristics.

The Proof is in the HEPA Filters

Here is the area where, perhaps, the clearest distinctions can be made between HEPA vacuums. Early in incorporating HEPA filters in portable vacuums, the HEPA filter was attached to a conventional vacuum's exhaust port. In many cases, the HEPA filter was necessarily undersized for its intended purpose. As the vacuum industry matured in its use of HEPA filtration, some manufacturers selected positioning the HEPA filter on the power source's inlet side. At the same time, some chose to stay with the filter positioned at the exhaust side.

What is best? The debate on this is inconclusive. Positioning the HEPA filter on the exhaust of the power source on an electric vacuum provides the ability to filter the carbon dust expelled by the motor brushes and allows contaminated air to contact the motors. Also, filter leaks are more critical when the filter is positioned on the exhaust as the filter is always in a positive pressure mode. When the HEPA filter is installed on the motors' intake side, the motors are better protected from contamination. The filter leaks issue is lessened due to the filter being in a negative pressure mode during operation.

It is also important to compare the size of the HEPA filter used in each machine. It stands to reason that the larger the filter, the longer it will perform between filter changes.

Make sure the HEPA filter is certified at the air displacement that the vacuum generates. If the filter is certified at a lower CFM air displacement than the vacuum generates, it will not perform at 99.97% efficiency.

Interestingly, HEPA filters actually become more efficient during their life span because the passages between the glass fiber filter medium reduce in size as the filter captures particles.

What's the difference in Filters? 

“True” HEPA filters must be individually tested and certified to meet the 99.97% efficiency at a 0.3-micron performance level. Each filter is subjected to a DOP test following Military Standard MIL-STD-282. DOP (dioctyl phthalate) is an oil that is used to create smoke with a very narrow particle size distribution. The particle size selected is 0.3 microns in diameter. Following the test, each filter that has passed is assigned a serial number, and the test results are recorded on the filter itself. If you are looking at a vacuum without this information on the filter, it is not a true HEPA vacuum.

HEPA-type filters are not subjected to the same rigorous testing as true HEPA filters and range in efficiency from 85% to 95%. Obviously, these units are less expensive than true HEPA units, but their filtering capability is unknown. Spending a few dollars more is easily justifiable when health and safety concerns are factored in.

Another Important Feature

Lower tier vacuums do not provide a means to determine when to replace the HEPA filter, causing the user to rely on guesswork. Unfortunately, this too often leads to too frequent or too infrequent filter replacement. Too frequent replacement is just a waste of money, while too infrequent replacement results in a period of time where the vacuum is used at less than ideal efficiency.

Look for machines that incorporate a device that tells the operator when to change the filter. Some models use a manometer to monitor the HEPA filter’s performance. In contrast, others use pressure differential devices that measure the pressure drop across the filter and give the operator a signal, such as a light, when it is time to replace the filter. These features may add a little to the machine's initial cost but usually result in a lower long-term ownership cost.

Conclusion

As you can see, purchasing a HEPA vacuum cleaner is not a decision to be taken lightly. Many factors must be weighed and features compared but armed with the right knowledge, it is a decision that can be made with confidence.