How to evaluate the quality of an air filter

1. Filtering efficiency (core within the core)

• Key parameters: filtration efficiency for particles of different sizes, especially PM0.3 (diameter approximately 0.3 micrometers). Because PM0.3 is the most difficult particle size to filter, it can efficiently filter PM0.3, which means it also has excellent effects on larger (such as PM2.5, pollen) or smaller (some viruses) particles.
• Standards and grades:
• International: HEPA standard (European EN 1822 or American DOE/IEST). The true HEPA (H13 and above grade) has a filtration efficiency of ≥ 99.95% for PM0.3. Pay attention to distinguishing marketing terms such as "HEPA type" and "HEPA style".
• China: GB/T 6165 "Performance Test Methods for High Efficiency Air Filters". H13/H14 levels correspond to international standards.
• American appliances: CADR value (clean air output ratio). Authorized certification by AHAM (American Association of Home Appliance Manufacturers). The higher the CADR value, the faster the purification speed. It is necessary to simultaneously check the three CADR values for smoke (small particles), dust (large particles), and pollen.

2. Dust holding capacity and service life

• Key parameter: CCM value (cumulative purification amount). The core indicator of the Chinese national standard (GB/T 18801) represents the "service life" of the filter screen. Grades range from P1 to P4 (particulate matter), F1 to F4 (formaldehyde). The higher the level (P4/F4), the longer the filter can be used and the lower the replacement cost. Prioritize selecting products with CCM reaching the highest level (P4/F4).

3. Balance between air volume and resistance (related to energy consumption and noise)

• High efficiency filters (such as HEPA) must have air resistance. A good filter design needs to strike a balance between high filtration efficiency, low air resistance, and long lifespan.
• Performance: Under the same CADR value, the lower the rated power, the higher the energy efficiency ratio and the more energy-efficient it is.

1. Types of pollutants

• Particulate matter (PM2.5, pollen, allergens, bacteria): The core depends on the HEPA filter level and CADR value.
• Gaseous pollutants (formaldehyde, TVOC, odor): Check the activated carbon filter. Focus on the weight, filling amount, and type of activated carbon (such as modified carbon and columnar carbon, which are better than crushed carbon). Is there a targeted decomposition technology (such as photocatalyst, cold catalyst), but attention should be paid to its actual effect and by-products.
• Microorganisms (viruses, fungi): HEPA filters themselves can physically trap them. Some products will add UV lamps, ion generators, etc. Attention should be paid to whether there is an authoritative sterilization report and whether the UV lamp is sealed (to prevent ozone generation).

2. Applicable area

• According to CADR value estimation: Applicable area ≈ CADR value × 0.1 (or 0.12). For example, a CADR of 500m ³/h purifier is suitable for rooms of 50-60 square meters. Better big than small.

1. Noise level

• Check the noise level (dB) of the product at different air volume levels (especially sleep/lowest level). A sleep noise level below 35 decibels usually does not affect rest. It is normal for the highest gear to produce loud noise, but the mid-range noise should be acceptable for daily use.

2. Maintenance cost and convenience

• Filter replacement cost: Check the official filter price and recommended replacement cycle, and calculate the average annual usage cost. Some brands of filters are expensive.
• Filter replacement reminder: Is there an intelligent reminder function (based on time or accumulated pollutants).
• Body cleaning: Is the design easy to wipe and clean.

3. Safety and side effects

• Ozone release: Technologies such as electrostatic dust collection, ion generators, and ultraviolet lamps (non enclosed) may generate ozone. Products that meet safety standards (such as the Chinese national standard limit of 0.1mg/m ³) and have authoritative testing reports should be selected. Especially important for sensitive populations.

1. Third party authentication

• Priority should be given to products with AHAM CADR certification, allergy friendly certification from authoritative institutions such as T Ü V Germany and ECARF, and "disinfectant product filing" from the Chinese Health Commission (if it has bactericidal function). These are reliable endorsements of performance.

2. Brand and reputation

• Choose mainstream brands with accumulated technology in the field of air purification, whose product performance data is more reliable and after-sales service is more comprehensive. View long-term evaluations from real users.