A laboratory decoration purification system is not a single product - it's a set of methods, each with different strengths, limitations, and cost profiles. Facility managers and lab planners generally choose among electrostatic, physical (mechanical/adsorption), chemical, and other purification approaches depending on the pollutant type, room size, and compliance requirements.
1. Electrostatic Purification Method
Working principle: Electrostatic purification relies on high-voltage static adsorption to remove dust. Under high-voltage static electricity, the cathode line in the electrostatic field generates corona discharge, producing a large volume of negative ions in the corona layer. Driven by the electrostatic field, these negative ions move continuously toward the anode. As dust in the air passes through the field, collisions with negative ions charge the dust particles. The charged dust is then pulled toward the anode (the dust collector) by the same electrostatic field and releases its charge once it reaches the anode.
Limitations: Electrostatic units can capture airborne dust, but they generally cannot remove toxic gases. Performance and response speed also tend to lag behind mechanical filtration, and the process can generate ozone as a byproduct. Partly for this reason, this category is often rated among the weaker options in independent purifier testing in the US market.
In practice: If a lab's main concern is particulate load rather than VOCs or gases, electrostatic purification can still play a supporting role - but it's rarely sufficient as a standalone solution in a space where chemical fume control matters.
2. Physical Purification Methods
2.1 Adsorption Filtration - Activated Carbon
Activated carbon is a porous, carbon-based material with a highly developed pore structure. This structure gives it a large internal surface area, allowing extensive contact with gas-phase impurities and, as a result, strong adsorption performance. In much the same way magnetic materials attract metal particles, activated carbon molecules have a natural attraction to many airborne pollutants, which makes it well suited to absorbing and collecting impurities.
Limitations: Standard activated carbon does not adsorb every toxic gas equally well. Efficiency tends to decline over time, and desorption - where previously captured pollutants are released back into the air - is a known failure mode, especially once the carbon bed nears saturation.
In practice: Carbon media should generally be treated as a consumable with a defined replacement schedule, not a one-time install. Buyers should ask suppliers for expected saturation timelines under their specific pollutant load.
2.2 Mechanical Filtration - HEPA
HEPA (High Efficiency Particulate Air) filters meet a defined efficiency standard: capturing 99.998% of particles at 0.3 microns, the particle size considered most difficult to filter (the "most penetrating particle size"). The defining feature of a HEPA filter is that it allows airflow through while blocking small particles from passing. Structurally, a HEPA filter is built from a stack of continuous sub-micron glass fiber membranes, folded back and forth into a wavy pleated gasket that both supports the filter media and maximizes surface area within a compact footprint.
In practice: HEPA filtration is a common baseline in cleanroom and lab HVAC design, but efficiency claims should be backed by test reports (typically DOP or PAO testing) rather than taken at face value - this is worth requesting during vendor evaluation.
3. Chemical Purification Methods
3.1 Photocatalyst Method
Working principle: Under ultraviolet light, a photocatalyst material promotes a chemical reaction that breaks down harmful substances. Airborne pollutants such as formaldehyde and benzene degrade under photocatalysis into non-toxic, harmless byproducts, while UV exposure also helps eliminate airborne bacteria - purifying the air through a combination of chemical breakdown and disinfection.
Limitations: This method is broad-spectrum in what it can target, but it generally requires a low airflow rate to be effective, which slows overall purification speed. It also introduces some level of radiation exposure to occupants, which is a key reason this approach has largely been phased out in Europe and the United States.
3.2 Formaldehyde Scavenger
Working principle: Formaldehyde scavengers use chemical substances that react directly with formaldehyde to neutralize it. They generally fall into four categories:
- Chemical reaction type: Reacts with formaldehyde to produce carbon dioxide and water - ammonia-based compounds are a common example.
- Biological type: Made from biological agents that react with formaldehyde, such as urea, soy protein, or amino acids.
- Plant-based type: Derived from plant extracts, such as aloe vera or tea extracts.
- Sealant type: Film-forming substances - like chitosan or liquid paraffin - that create a barrier to prevent formaldehyde release rather than breaking it down.
Limitations: Two issues come up regularly in practice. First, byproducts from the chemical reaction can introduce secondary pollution, and re-testing after treatment sometimes shows levels exceeding standards again. Second, methods that only absorb formaldehyde without altering its chemical structure reduce airborne concentration temporarily but don't address the source - formaldehyde tends to be released again over time.
3.3 Cold Catalyst Method
Working principle: Cold catalyst - also known as natural catalyst - is a newer air purification material developed after photocatalyst technology, and it can initiate a catalytic reaction at normal temperature and pressure. This lets it decompose a range of odorous, harmful gases into harmless, odorless byproducts without needing added heat or UV. Rather than relying on simple physical adsorption, cold catalyst combines adsorption with decomposition - breaking down formaldehyde, benzene, xylene, toluene, and total volatile organic compounds (TVOC) into water and carbon dioxide.
The catalyst itself does not get consumed in the reaction: it doesn't change chemically or degrade over repeated cycles, which allows it to provide a long service life. It's also non-toxic, non-corrosive, and non-combustible, and because the reaction products are water and carbon dioxide, it avoids the secondary pollution risk seen in some chemical scavenger approaches.
In practice: Because cold catalyst doesn't rely on UV or high airflow, it tends to suit labs where continuous, low-maintenance VOC control matters more than rapid particulate removal - though it's generally deployed alongside HEPA or activated carbon rather than as a complete replacement.
4. Other Purification Methods
4.1 Water Washing Method
This method applies siphon and centrifugal principles together. A motor-driven coaxial centrifugal turbine draws purifying agent mixed with water into a suction pipe at its base via siphon action. An AC shaded-pole motor spins the assembly at high speed, spraying water inside the unit's housing to form a water film. This film captures dust and bacteria from the air as it passes through, while purified air is released back into the room. The process is generally effective at removing dust, smoke, odor, and some airborne pathogens, and it has the side benefit of increasing humidity and oxygen levels in the space.
4.2 Negative Ion Method
Hydroxyl negative ions can reduce the reactive oxygen species (oxygen free radicals) generated when atmospheric pollutants, nitrogen oxides, and cigarette smoke interact with air - lowering the potential harm reactive oxygen poses to occupants. Negative ions also neutralize positively charged particles in the air; once neutralized, these particles settle out of suspension, which helps purify the air.
Choosing the Right Purification System for Your Lab
No single method covers every pollutant type, which is why most lab decoration projects end up combining two or more approaches - commonly HEPA filtration for particulates paired with activated carbon or cold catalyst for gas-phase pollutants. Before finalizing a system, it's worth confirming a few things with your supplier:
Test data, not just claims. Ask for third-party efficiency reports (e.g., 0.3-micron DOP/PAO testing for HEPA units) and ozone emission data for electrostatic components.
Consumable costs and availability. Activated carbon and HEPA media need periodic replacement - get expected service intervals and part lead times up front.
Airflow and HVAC compatibility. Some methods (photocatalyst, water washing) require specific airflow ranges to perform as rated; confirm compatibility with your existing or planned HVAC design.
Compliance requirements. Depending on your lab classification, you may need to meet ISO 14644 cleanroom standards, local building codes, or occupational exposure limits - confirm the system's certifications match your jurisdiction.
Integration with fume hoods and exhaust. For labs handling volatile chemicals, purification should be planned alongside - not instead of - proper fume hood exhaust design.
These are the kinds of specification details that tend to separate a purification system that performs as expected from one that underdelivers once installed.
Everything You Need to Know
What is the best purification method for a laboratory decoration project?
There's generally no single "best" method - most labs combine HEPA filtration for particulates with activated carbon or cold catalyst for gas-phase pollutants like formaldehyde and benzene, based on the specific chemicals and processes used in the space.
Is electrostatic air purification suitable for laboratories?
Electrostatic purification can help with airborne dust, but it typically can't remove toxic gases and may generate ozone as a byproduct, so it's rarely used as a standalone system in labs handling chemical fumes.
How often does HEPA filter media need to be replaced in a lab setting?
Replacement intervals depend on airflow, particulate load, and lab activity level - suppliers should provide expected service life based on testing data rather than a generic estimate.
What's the difference between a cold catalyst and a photocatalyst purification system?
Cold catalyst works at normal temperature and pressure without UV light, offering longer-term, low-maintenance VOC breakdown, while photocatalyst requires UV exposure and low airflow to be effective and has largely been phased out in Europe and the US due to radiation concerns.
If you're planning a laboratory decoration or renovation project and need help matching purification methods to your space, ventilation load, and compliance requirements, BOKA's project team can walk through your specifications and recommend a system configuration suited to your lab. Get in touch with our team to discuss your project.