Air Scrubbing and HEPA Filtration — Utah County

Air scrubbing is the process of removing airborne particulates from a defined work area using high-efficiency filtration equipment. In restoration contexts, air scrubbers serve two functions: capturing airborne particulates that get generated by cleaning, demolition, or drying work, and maintaining negative pressure within containment to prevent cross-contamination to unaffected areas. Vault Mold Removal deploys HEPA air scrubbers — specifically Novatek NA-1500 units — across every containment project in Utah County, scaled to the volume of the containment and the specific work being performed. This page describes what HEPA air scrubbing actually does, how equipment sizing decisions are made, and what property owners should understand about the technology.

What HEPA Actually Means

HEPA (High-Efficiency Particulate Air) is a filtration standard defined by capturing particles down to 0.3 microns at 99.97% efficiency. The 0.3 micron figure is important because that’s the “most penetrating particle size” (MPPS) — particles smaller than 0.3 microns are captured through diffusion, particles larger than 0.3 microns are captured through impaction and interception, and 0.3 microns is the size that’s hardest to capture. Filters that meet the HEPA standard at 0.3 microns capture other particle sizes at higher efficiency.

For context, particle sizes relevant to restoration work:

• Mold spores: typically 2–20 microns depending on species (well above HEPA’s most-difficult size)
• Smoke particles: 0.4–1 microns (larger fraction) and much smaller submicron particles (harder to capture)
• Bacteria: 0.5–5 microns
• Viruses: 0.02–0.3 microns
• Dust: 1–100+ microns
• PM2.5 particulate matter: 2.5 microns (well within HEPA capture range)

Standard consumer air purifiers and residential HVAC filters typically don’t meet HEPA standards. MERV 13–16 HVAC filters approach but don’t quite reach HEPA performance. True HEPA filtration requires industrial-grade equipment specifically designed and tested to the HEPA standard.

Novatek NA-1500 Specifications

Our standard air scrubber is the Novatek NA-1500 unit, chosen for airflow capacity, filtration performance, and reliability in restoration work environments. Specifications:

• Airflow capacity: 1,500 CFM (cubic feet per minute) at nominal operation, adjustable through multi-speed operation
• Primary filtration: HEPA filter meeting the 0.3 micron / 99.97% standard
• Pre-filter: MERV 8 pre-filter that extends primary HEPA filter life by capturing larger particulates
• Optional activated carbon filter for VOC and odor absorption (deployed for smoke odor and other chemical situations)
• Portability: wheel-mounted for easy positioning
• Ducting compatibility: 12-inch or 16-inch flexible ducting for directional airflow to exterior or between spaces
• Power: standard 15-amp/120V household circuit

Multiple units can be deployed in parallel for larger containment volumes, scaled to meet the required air changes per hour (ACH) for the specific work being performed.

Air Changes Per Hour (ACH) Calculations

ACH is the fundamental unit for air scrubbing scope calculation. It’s the number of times the total air volume in a containment area is filtered per hour. Higher ACH means faster air cleaning and more effective particulate capture.

Standard ACH Targets by Work Type

• General work areas during cleaning: 4–6 ACH
• Mold remediation containment: 6–12 ACH depending on colony size and disturbance
• Category 3 sewage containment: 8–12 ACH
• Asbestos or lead abatement: 12+ ACH per specific regulations
• Fire restoration active cleaning: 6–10 ACH
• Post-work spore reduction before verification: 8–12 ACH for extended period

Sizing Example

A 15′ × 20′ room with 9′ ceilings has volume of 2,700 cubic feet. Achieving 8 ACH requires 21,600 cubic feet per hour of air movement, or 360 CFM. A single Novatek NA-1500 at 1,500 CFM easily exceeds this, so one unit is adequate for the space. For a larger containment (say 30′ × 40′ with 12′ ceilings = 14,400 cubic feet), achieving 8 ACH requires 1,920 CFM — two units running in parallel meet the requirement.

Positive vs. Negative Pressure Applications

Negative Pressure Operation

Most restoration containment uses negative pressure — the air scrubber exhausts air to exterior (or to an area that’s already contaminated), pulling air into the containment through controlled openings. This creates slight negative pressure inside the containment relative to surrounding spaces, ensuring that any containment breach results in air flowing INTO the work area rather than contaminated air escaping OUT of the work area.

Negative pressure verification uses a manometer measuring pressure differential between containment interior and adjacent spaces. Target: -0.02 to -0.05 inches water column. Continuous monitoring during work ensures containment integrity is maintained.

Applications: mold remediation, Category 3 sewage cleanup, asbestos abatement, lead work, and any situation where contamination inside containment must not escape.

Positive Pressure Operation

Positive pressure operation blows filtered air into a defined space, creating slight positive pressure that pushes air outward through controlled openings. This prevents contaminated air from external sources from entering the pressurized space.

Applications: preventing dust migration into unaffected areas during construction, protecting clean rooms or occupied areas adjacent to work zones, and creating temporary clean environments for sensitive activities.

General Filtration Without Pressure Control

Some applications just need air cleaning without pressure differential requirements — general dust reduction during cleaning, allergen removal for occupant comfort, or ongoing particulate reduction in a treated space. Air scrubbers can operate in recirculating mode (filtering air within a space rather than exhausting to exterior) for these applications.

Deployment During Specific Restoration Work

Water Damage Structural Drying

Structural drying doesn’t require containment or negative pressure in most residential situations — the “contamination” is just moisture that the equipment is removing. Air scrubbers are deployed in some situations: Category 2 or 3 water damage where microbial amplification is a concern, drying areas that will re-open to occupied space frequently (allergen and dust control), and any situation where post-cleaning particulate is elevated.

Mold Remediation

Mold remediation requires negative pressure containment with HEPA-filtered exhaust as standard practice under IICRC S520. Air scrubber count depends on containment volume and target ACH; typically two or more units are deployed in larger residential and commercial situations.

Sewage Cleanup

Category 3 sewage cleanup requires negative pressure containment. Air scrubbers with activated carbon filters help address odor from sewage during the cleanup phase, in addition to particulate capture.

Fire Damage Cleaning

Fire damage cleaning generates significant airborne particulate as cleaning progresses. Air scrubbers with activated carbon filters address both particulate and smoke odor throughout the cleaning phase. Deployed both in active cleaning areas and in adjacent transition spaces to prevent particulate migration.

Post-Restoration Air Quality

Some situations warrant continued air scrubbing after restoration work is complete, particularly for smoke damage where residual odor and particulate reduction continues over 1–4 weeks. Occupant comfort and health considerations often drive this decision.

Filter Maintenance and Replacement

Filter performance degrades with use. Standard maintenance schedule:

• Pre-filter (MERV 8): Inspected daily during active use, replaced when visibly loaded (typically every 3–10 days depending on particulate loading)
• Primary HEPA filter: Rated for approximately 3,000 hours of use in typical restoration conditions. Replaced when static pressure across the filter indicates loading (typically 300–1,000 hours in heavy-particulate applications like fire cleaning)
• Activated carbon filter (when installed): Rated for approximately 3–6 months of typical use before adsorption capacity is depleted. Replaced when odor breakthrough becomes noticeable

Filter costs are included in project pricing rather than billed separately — equipment operation with degraded filters wastes energy and produces poor results, so filter replacement is standard operational cost rather than customer-billable extra.

Frequently Asked Questions

Can I just use a consumer HEPA air purifier instead of professional air scrubbers?

For general residential air quality improvement, yes — a consumer HEPA purifier can help reduce particulate and allergens. For restoration work, no — the airflow capacity difference is significant. Consumer HEPA purifiers typically move 100–300 CFM of air; professional restoration air scrubbers move 1,000–2,000 CFM. For a typical residential room at 2,500–3,000 cubic feet, achieving even 4 ACH requires roughly 200 CFM, which many consumer units can achieve. But achieving the 8–12 ACH needed for mold remediation or sewage cleanup requires 400–600 CFM, which is beyond consumer equipment capability. Additionally, consumer purifiers don’t maintain negative pressure containment, don’t have exterior exhaust capability, don’t provide continuous filter loading monitoring, and don’t produce documentation for restoration project records. For general room air quality, consumer purifiers work. For restoration containment, professional equipment is required.

Do you leave the air scrubber running when nobody’s on-site?

Yes, typically. Air scrubbers operate 24/7 during containment situations to maintain negative pressure and continuous filtration. Interrupted operation would cause loss of negative pressure (allowing contamination migration), interrupted air cleaning (allowing airborne particulate accumulation), and interrupted drying acceleration (in situations where drying is ongoing). The units are designed for continuous operation, and the power draw (typically 200–400 watts on high speed, less on lower speeds) is manageable. When the property is unoccupied, we set up equipment to run safely with automatic shutdown protections and monitor operation remotely when possible. Property owners occasionally ask about turning off equipment during specific hours; this is not recommended and would compromise the restoration work.

Is the noise level from air scrubbers a problem during residential work?

It’s noticeable but generally tolerable. Novatek NA-1500 units at nominal operation produce approximately 60–65 decibels at 10 feet — comparable to normal conversation or background office noise. At close range (within 3 feet), noise level is higher, but restoration equipment is typically positioned away from occupied living spaces. Lower speeds produce less noise at the tradeoff of reduced airflow. For occupied properties where reduced noise is important (bedrooms adjacent to containment during sleeping hours, for example), we can typically adjust equipment speed and positioning to reduce impact. For unoccupied restoration work, noise isn’t a consideration.

Does air scrubbing eliminate the need for surface cleaning?

No. Air scrubbing captures airborne particulates only — particles that are actually suspended in the air at the moment they pass through the filter. Residue that has settled onto surfaces, penetrated into porous materials, or become bound to substrates isn’t captured by air scrubbing regardless of how long it runs. Surface cleaning is a separate work stream that removes settled and adherent contamination. Air scrubbing supports surface cleaning by capturing particulate that gets disturbed and airborne during the cleaning process, but it doesn’t replace surface cleaning. In practice, air scrubbing and surface cleaning happen in parallel — air scrubbers running continuously during cleaning work capture the particulate that surface cleaning inevitably disturbs.

How long does air scrubbing typically continue after visible work is complete?

Depends on the specific project. For mold remediation, air scrubbing typically continues for 24–48 hours after physical work is complete but before verification testing, to allow airborne spore levels to normalize before samples are taken. For fire and smoke damage, air scrubbing often continues for 1–2 weeks after visible cleaning is complete to address ongoing off-gassing of residual chemical contamination. For water damage, air scrubbing typically ends when structural drying is complete. Total air scrubbing duration is documented in the project scope and adjusted based on actual conditions during work.

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Contact Vault Mold Removal — Provo, UT

For projects requiring HEPA air filtration and containment, standalone air scrubbing after prior work, or questions about specific air quality scenarios, contact our office directly.

• Phone: (385) 250-2825
• Address: 1169 S 760 W, Provo, UT 84601
• Utah DOPL General Contractor License: #11876543-5501
• IICRC WRT / ASD / AMRT / OCT: #248317 / #248317-ASD / #319482 / #319482-OCT

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• Sunday: Closed