Air Purifier CADR Rating Guide: How to Choose for Room Size
Air Purifier CADR Rating Guide: How to Choose for Room Size
Pain Points / Background
Buying air purifier without understanding CADR leads to underpowered units. People buy based on brand not room coverage. CADR is key metric.
Decision Framework
CADR = Clean Air Delivery Rate. Need CADR >= room area x 2 for good performance. Dust CADR most important, pollen and smoke follow.
Test Comparison Table
| Room size | Required CADR | Purifier type |
|---|---|---|
| <150 sq ft | 150+ | Small |
| 150-300 sq ft | 200-300 | Medium |
| 300-500 sq ft | 350+ | Large |
Pitfalls to Avoid
- Ignoring CADR rating
- Buying based on HEPA filter only
- Not considering noise levels
- Oversized unit for room
- Not replacing filters on schedule
- Hiding unit in corner
Pro Tips
Check AHAM verified CADR. Place unit 3-5 feet from bed. Clean pre-filters monthly. HEPA lasts 6-12 months. Look for auto mode.
FAQ
Q1 What is good CADR? 200+ for bedrooms. Q2 Can one unit cover whole house? No, need per room. Q3 Noise levels? <45dB for bedroom. Q4 HEPA 13 vs 11? 13 better for allergens. Q5 How often replace filters? Every 6-12 months. Q6 CADR vs room size formula? CADR >= room sq ft * 2.
Declaration: Based on public product specs and user reviews