Air Scrubber vs Negative Air Machine: What You Need to Know

Air Scrubber vs Negative Air Machine: What You Need to Know

In the quest for clean, healthy air, two devices often come to the fore: air scrubbers and negative air machines. Air scrubbers and negative pressure air machines are essential in maintaining air quality, especially in contexts such as post-fire restoration, construction work, or even in homes where air quality is a significant concern. With their high-efficiency filters and powerful motors, these devices are designed to remove contaminants and ensure the air we breathe is as clean and safe as possible.

Due to the increase of allergens, VOCs, molds, and other air pollutants, these air purification tools have become necessary for homeowners and even industrial or office complexes.

But which should you go for? An Air Scrubber or a Negative Air Machine? This content will compare both devices to help you make an informed decision. But first, let's get to know them.


What is an Air Scrubber?

Air Scrubbers

An air scrubber is a portable filtration system that removes particles, gases, and/or chemicals from the air in an area like your office or home. Air scrubbers work by filtering air through high-efficiency particulate air (HEPA) filters and multi-function filtration system. They are particularly effective at removing air pollution, volatile organic compounds (VOCs), surface contaminants, pet dander, and odors.


The primary function of an air scrubber is to improve air quality by filtering out pollutants such as dust, mold spores, pollen, and odors. They are commonly used in construction sites, mold remediation, and homes or businesses to improve indoor air quality.


What is a Negative Air Machine?

Negative Air Machine

A negative air machine, also known as an air mover, is designed to create negative pressure within a specific area. This machine effectively contains airborne contaminants within a designated area, preventing them from spreading to other locations. It does this by creating a 'negative pressure' environment, where the air pressure inside a room or containment is lower than the pressure outside. This pressure difference allows clean air to flow into the containment while the contaminated air is safely vented outside.


It works by drawing in dirty air, filtering it through HEPA filters to remove contaminants, and then exhausting the clean air outside the containment area. Negative air machines are essential in environments where containment of hazardous particles like mold, asbestos, or dust is critical, such as in hospitals, construction sites, and mold remediation projects.


What Differentiates the Two?

The main difference between an air scrubber and a negative air machine lies in their primary function and application. An air scrubber primarily cleans and purifies the air within a space, focusing on removing airborne pollutants. In contrast, a negative air machine creates a negative pressure environment that prevents the spread of contaminants to other areas, filtering the air as it is exhausted out of the space.


Air scrubbers can be used as negative air machines when connected to ventilation ducts. This method focuses on creating a negative pressure environment where air is forced to flow from inside the room to the outside while filtering out various pollutants from the air. When air scrubbers are connected to ventilation ducts, this process can be applied to an entire room or building.


The Purisystems HEPA 600 UVIG commercial Air scrubber is an example of a powerful unit with a three-stage filtration system that includes an activated carbon filter and a HEPA filter that effectively removes 99.97% of particles, gases and odors. With their rugged construction and high airflow capabilities, Purisystems air scrubbers are often used to create healthy, safe environments for manufacturing plants, schools and home basements. (Residence: Each air scrubber can be connected to different duct diameters.)

HEPA 600 UVIG Air Scrubber With Duct Pipe


How does an Air Scrubber Work?

An air scrubber pulls in air from the surrounding environment and passes it through a series of filters to remove contaminants. The core components of an air scrubber include a fan, filters, and sometimes additional technology for more advanced purification. Here's a step-by-step breakdown of the process:


Air Intake: The fan draws air from the surrounding area into the unit.

Pre-Filtration: The air first passes through a pre-filter designed to capture large particles, such as dust and hair, to extend the life downstream of the more refined filters.

Primary Filtration: After the pre-filter, the air moves through a primary filter. High-efficiency particulate air (HEPA) filters are commonly used at this stage, capable of capturing 99.97% of particles as small as 0.3 microns, including pollen, mold spores, and certain bacteria.

Secondary Filtration or Treatment: Some air scrubbers are equipped with additional filtration or treatment stages, such as activated carbon filters for removing gases and odors or UV-C light to kill bacteria and viruses.

Air Exhaust: The cleaned air is then released back into the room or area, significantly improving the indoor air quality.


This process continuously cycles the air in a room through the scrubber, progressively reducing the concentration of airborne contaminants.


How Does a Negative Air Machine Work?

A negative air machine operates by creating a negative pressure environment, which is essential in preventing the spread of contaminated air to adjacent spaces. Here's how it achieves this:


Air Intake: Similar to an air scrubber, the machine draws contaminated air from the room through a powerful fan system.

HEPA Filtration: The air is then forced through HEPA filters, which capture particles as small as 0.3 microns with a 99.97% efficiency rate. This includes dust, mold spores, asbestos fibers, and other hazardous particles.

Negative Pressure Creation: By continuously extracting air from the room and not allowing it to circulate back, the machine creates a lower pressure inside the room compared to the surrounding areas. This negative pressure ensures that when doors or other openings are used, air flows into the room rather than out of it, preventing the escape of contaminants.

Clean Air Exhaust: The filtered air is then exhausted outside the containment area or building through ducting. This ensures the contaminated air does not re-enter the space or spread to other areas.


What are the Air Scrubbers Advantages?

Improved Air Quality: Air scrubbers effectively remove a wide range of airborne contaminants, including VOCs, dust, pollen, and odors, significantly improving indoor air quality.

Versatility: They can be used in various settings, from residential homes to commercial and industrial sites.

Health Benefits: By removing harmful pollutants, air scrubbers can reduce the risk of respiratory problems and other health issues related to poor air quality.

Odor Elimination: Besides removing particles, they can also neutralize odors, making them ideal for use in areas affected by smoke, pets, or chemical smells.


What are the Negative Air Machine Advantages?

Containment of Contaminants: By creating negative pressure, these machines prevent the spread of hazardous particles to other areas, ensuring a safer environment.

Compliance with Regulations: Health and safety regulations often require negative air machines in settings where contamination control is critical, such as in asbestos abatement.

Versatility in High-Risk Environments: They are essential in hospitals, construction sites, and during mold remediation, where controlling the spread of contaminants is crucial.

High-Efficiency Filtration: Equipped with HEPA filters, they can capture 99.97% of particles as small as 0.3 microns, ensuring thorough air purification.


Which is Best for You?

Choosing between an air scrubber and a negative air machine depends on your specific needs:


For Improving Indoor Air Quality: If your primary goal is to purify the air by removing pollutants and odors, an air scrubber is the better choice.

For Contaminant Containment: If you need to prevent the spread of hazardous materials during renovation, construction, or in a healthcare setting, a negative air machine is more suitable.



Both air scrubbers and negative air machines play vital roles in maintaining clean and safe air quality in various environments, but they do so in fundamentally different ways. Air scrubbers focus on purifying the air within a space by removing airborne pollutants through a series of filters, making them ideal for improving indoor air quality and protecting the health of occupants. On the other hand, negative air machines are designed to create a negative pressure environment that prevents the spread of hazardous particles to adjacent areas, ensuring that contaminated air is contained and safely removed from the premises.


Choosing between an air scrubber and a negative air machine—or deciding to use them in conjunction—depends on the situation's specific needs, including the type of contaminants present, the goal of air purification versus containment, and the environmental regulations that may apply. 


Understanding how each device works allows individuals and professionals to make informed decisions to ensure the health and safety of indoor environments, whether in residential settings, construction sites, healthcare facilities, or any area where air quality is a concern.

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