Methodology & data provenance
Source and capture
PureAirIndex analyzes published ENERGY STAR Certified Room Air Cleaners V3.0 certification data. We do not independently test products and are not affiliated with the EPA or AHAM. Captured at 2026-10-20T00:55:00.876Z; certification dates describe individual records, not retrieval.
The feed returned 247 rows; 247 were included and 0 excluded. Inclusion requires finite positive smoke CADR and reported room area. There is one row per ENERGY STAR ID; product families and brand variants are not deduplicated. The feed is not a census of the retail market. Pagination, source count and unique-ID checks help detect incomplete retrieval but do not provide a transactionally frozen source version.
Room sizing and model matching
Required smoke CADR (cfm) = floor area (ft²) × ceiling height (ft) × selected equivalent air changes per hour ÷ 60. Calculated area = smoke CADR × 60 ÷ (eACH × ceiling height). The default comparison uses 4.8 eACH and 8 ft; eACH is equivalent clean-air delivery from filtration, not outdoor-air ventilation or a medical recommendation.
Matches require positive, finite smoke CADR at or above the unrounded requirement. They are sorted by the lowest sufficient smoke CADR, then source ID to break ties. No retail facts, energy values or brand preferences influence the match rule. The optional brand filter narrows the displayed rows only. A blank, zero, negative or nonfinite room input produces no calculation.
Reported room area remains separate from our calculated scenarios. The study compares (calculated − reported) ÷ reported × 100 for every included row; it does not apply a pass/fail tolerance or imply that a discrepancy is a manufacturer error. The CSV retains calculation precision; study tables use one decimal, calculator CADR rounds up and its calculated areas round down.
Energy and retail facts
Derived operating watts = reported smoke CADR ÷ reported smoke CADR-per-watt, rounded to one decimal. This is not our power measurement. Annual electricity cost = ENERGY STAR-reported annual kWh × the selected $/kWh rate (default $0.16). Reported annual energy is distinct from a constant-wattage 24/7 scenario: watts × 24 × 365 ÷ 1,000.
Two-year cost = entered purchase price + annual kWh × rate × 2 + entered annual filter cost × 2. Prices, filter costs and marketing claims are not EPA fields and must not be inferred from certification. Unverified values are not product facts.
Reproduce the analysis
The source manifest includes the exact query and SHA-256 checksums of the archived, JSON-serialized source rows and normalized snapshot. Normalization trims model text, maps named fields and derives watts; the original archived rows remain separate. To reproduce the current coverage CSV using the project source:
bun scripts/export-room-coverage.tsFor a new capture, run the following first. This replaces the snapshot and archives a new source state; it does not reproduce a historical feed response.
bun scripts/fetch-energystar.tsLimitations and review
No claims about gases, noise, health outcomes, room mixing, filter life or lower-speed performance follow from these calculations. We make no verified manufacturer-claim comparison. This analysis has not received independent statistical or air-cleaner standards review; no reviewer endorsement is implied.
For an apparent source error, compare the exact ENERGY STAR ID with the live feed. For a calculation discrepancy, retain the room inputs and downloaded manifest so the result can be reproduced.