How Long Should an Air Scrubber Run?

How Long Should an Air Scrubber Run?

Air scrubbers are essential tools for improving indoor air filtration and protecting human health. Their function is to remove particles, gases, airborne pollutants, and other contaminants from the air, making it cleaner and healthier to breathe.

But how long should you run your air scrubber? The answer depends on a number of factors, including the level of air pollution in your home, the size of your space, and the type of air purifier you have.

In this blog post, we'll discuss how to determine the operating time of your air scrubber and give you tips for getting the most out of your appliance.


How does an air scrubber work?

Here are the three key processes in the operation of air scrubbers:

Filtration: Air scrubbers often use filters to trap and remove solid particles from the air. Different types of filters may be used depending on the size and nature of the particles to be removed. Common filter types include High-Efficiency Particulate Air (HEPA) filters, activated carbon filters, and electrostatic precipitators.

Chemical treatment: Some industrial-strength air scrubbers employ chemical reactions to neutralize or remove harmful gases and odors from the air. These systems typically use substances such as activated carbon, potassium permanganate, or other specialized chemicals to absorb or chemically react with the pollutants.

Ventilation: Once the air has been purified, it is released back into the environment. Proper ventilation is essential to ensure that the purified air circulates effectively throughout the space, maintaining a clean and healthy atmosphere. 


Factors affecting the operating time of air scrubbers


While negative air machine offer numerous benefits for improving indoor air quality. Determining the appropriate time to run an air scrubber is crucial for optimal performance and efficiency.


Industry Standard Run Time

The industry standard for air scrubber operation is between 24 to 48 hours. This recommendation is based on the assumption that commercial air scrubbers or portable air scrubbers have a clean air delivery rate (CADR) of 400 to 600 cubic feet per minute (CFM) and can achieve four air changes per hour (ACH). ACH refers to the number of times the air volume in a room is filtered within an hour.


Factors Influencing Run Time

Several factors can influence the time to run an air scrubber, including:

Air Quality and Pollution Levels: Higher levels of pollutants, such as particulate matter (PM), volatile organic compounds (VOCs), and harmful gases, necessitate longer operating times to effectively purify the air. In severely polluted environments, continuous operation or frequent cycles may be required to maintain desirable air quality.

Size and Layout of the Space: The size and layout of the area where the air scrubber is being used also affect its operating time. Larger spaces or those with complex layouts may require longer operating times to ensure that purified, clean air circulates effectively throughout the space.

Type and Performance of the Air Scrubber: Different types of air scrubbers have varying levels of effectiveness in removing specific pollutants. High-performance air scrubbers may require less operating time to achieve the desired air filtration compared to models with less efficient air scrubber filters.

Energy Consumption and Cost: Energy consumption and operating costs can also limit the feasible operating time of an air scrubbers. Some air purifiers may consume more energy during operation, leading to higher operational costs and potentially limiting the feasible operating time based on budget constraints.


Additional Considerations

Filter Maintenance: Regularly changing filters is essential to maintaining the efficacy of an air purifier. A clogged filter reduces airflow, diminishing the number of air changes per hour the unit can achieve.

Space Containment: In cases of mold remediation or renovation projects, it may be necessary to isolate the affected area using plastic sheeting or barriers. This containment strategy enhances the effectiveness of the air scrubber in mold remediation by preventing contaminants from escaping the area.

Professional Consultation: For complex air filtration issues or situations involving extensive contamination, consulting with a mold remediation or renovation professional is highly recommended. They can assess the specific conditions and provide guidance on the appropriate air filtration devices, air scrubber selection, placement, and operating schedule.


Comparison of continuous operation and intermittent operation of air scrubbers

Advantages of Continuous Operation

1. Consistent air quality: Continuous operation of the air purifier ensures a steady purification process, maintaining a consistently high level of air quality without fluctuations.

2. Efficient removal of contaminants: Continuous operation effectively removes and prevents the buildup of pollutants, ensuring that the air remains clean and safe at all times. 

3. Ideal for high-pollution environments: In settings with consistently high levels of contaminants such as airborne pollutants, continuous operation is essential for maintaining a healthy indoor environment.


Disadvantages of Continuous Operation

1. Higher energy consumption: Continuous operation can lead to increased energy consumption, resulting in higher operational costs and potential environmental impacts.

 2. Wear and tear: Continuous operation may lead to more frequent wear and tear of the air scrubber components, potentially reducing its lifespan and requiring more frequent maintenance.

Advantages of Intermittent Operation

1. Energy efficiency: Intermittent operation reduces overall energy consumption, leading to lower operational costs and a reduced environmental footprint.

2. Extended lifespan: Intermittent operation can help prolong the lifespan of the air scrubber by reducing wear and tear on its components during periods of lower demand.

 3. Cost-effective: In environments with moderate air quality fluctuations, intermittent operation of air scrubbers proves more cost-effective and energy-efficient.


Disadvantages of Intermittent Operation:

1. Fluctuating air quality: Intermittent operation may lead to fluctuations in air quality, especially during periods when the air scrubber is not actively purifying the air, potentially allowing pollutants to accumulate. 

2. Reduced effectiveness in high-pollution environments: In settings with consistently high levels of contaminants, intermittent operation may not be sufficient to maintain a consistently healthy indoor environment.


Selecting The Appropriate Mode of Operation Based On Demand

Selecting The Appropriate Mode

In seasons or weather conditions with heavy pollution, such as haze weather and environments where the concentration of pollutants remains high, consider increasing the running time of the air scrubber to keep the indoor air fresh.

If a family member has allergies or respiratory problems, run the air scrubber continuously to ensure the level of air purification. For rooms with fluctuating air quality and rooms that are only used occasionally, such as storage or guest rooms, choose intermittent operation to reduce energy consumption.

Use an air scrubber equipped with an air quality monitoring function to monitor air conditions in real-time. Based on the monitoring results, the operating mode is adjusted to ensure that the purification effect is improved when necessary.


Air scrubber maintenance and filter replacement

Regular cleaning and maintenance of the air purifier is essential to ensuring their optimal performance and longevity.  

1. Prevents contamination buildup: Regular cleaning prevents the buildup of contaminants within the system, ensuring that the air scrubber operates efficiently and effectively.

2. Sustaining air quality: Proper maintenance helps maintain the desired air quality levels by ensuring that the air scrubber functions at its best capacity, removing pollutants, and maintaining a healthy indoor environment. 

3. Extends lifespan: Routine maintenance can extend the lifespan of the air scrubber by reducing wear and tear and preventing potential damages that could result from neglect or inadequate care.

4. Reduces energy consumption: A well-maintained air scrubber operates more efficiently, leading to reduced energy consumption and lower operational costs.


When and How to Change Filters

To maintain the effectiveness of your air scrubber, it's crucial to know when and how to replace its filters. Air scrubbers typically have three layers of filters: a pre-filter, an activated carbon filter, and a HEPA filter.


Pre-filter Replacement

The pre-filter, which captures larger particles like dust and pet hair, should be replaced every 2-3 months, depending on the frequency of air scrubber use.


Activated Carbon and HEPA Filter Replacement

Purisystems' activated carbon and HEPA filters are combined into a single 2-in-1 filter. This filter, which removes odors, gases, and airborne particles, should be replaced every 6-8 months.


General Filter Replacement Guidelines

In addition to the specific replacement intervals mentioned above, follow these general guidelines for maintaining your air scrubber's filters:

Monitor filter condition regularly: Regularly check the filters for signs of clogging or damage. Dirty or damaged filters can compromise the air scrubber's effectiveness.

Consider air quality: If you notice a decline in indoor air quality or a decrease in the air scrubber's performance, check the filters even if they haven't reached their maximum recommended lifespan.

Refer to manufacturer's recommendations: Always consult the manufacturer's instructions for the specific type of filters used in your air scrubber. The manufacturer will provide guidelines on recommended filter lifespans based on usage and pollutant levels.



Air scrubbers are an effective and efficient way to improve indoor air quality and reduce the risk of respiratory problems and other health conditions. By carefully considering the factors discussed in this blog post, you can determine how long to run your air scrubber to get the most out of your device.

 Here are a few key takeaways:

● Air scrubbers should be run for as long as necessary to maintain a healthy air quality level.

● The operating time of an air scrubber will vary depending on the level of air pollution, the size of the space, and the type of air scrubber being used.

● It is important to consult with the manufacturer of your air scrubber to get specific instructions on how long and how often to run it.

● Regular maintenance of your air scrubber is also essential to ensure that it is operating efficiently and effectively. This includes replacing filters on a regular basis and cleaning the unit as needed.

By following these tips, you can ensure that your air scrubber from Purisystems is providing you with clean and healthy air for many years to come.

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