PM2.5 is 4.7 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 4.7/22 × 0.5 = 0.1 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 22.5 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 4.9 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 4.9/22 × 0.5 = 0.1 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 22.3 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 5.1 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 5.1/22 × 0.5 = 0.1 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 22.1 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 5.1 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 5.1/22 × 0.5 = 0.1 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 22.1 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 6.5 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 6.5/22 × 0.5 = 0.1 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 20.7 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 6.8 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 6.8/22 × 0.5 = 0.2 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 20.4 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 6.8 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 6.8/22 × 0.5 = 0.2 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 20.4 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 8.5 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 8.5/22 × 0.5 = 0.2 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 18.7 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 8.5 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 8.5/22 × 0.5 = 0.2 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 18.7 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 8.5 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 8.5/22 × 0.5 = 0.2 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 18.7 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 9.4 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 9.4/22 × 0.5 = 0.2 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 17.8 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 9.5 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 9.5/22 × 0.5 = 0.2 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 17.7 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 9.5 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 9.5/22 × 0.5 = 0.2 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 17.7 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 9.7 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 9.7/22 × 0.5 = 0.2 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 17.5 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 10.6 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 10.6/22 × 0.5 = 0.2 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 16.6 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 11.1 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 11.1/22 × 0.5 = 0.3 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 16.1 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 13.6 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 13.6/22 × 0.5 = 0.3 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 13.6 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 16.5 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 16.5/22 × 0.5 = 0.4 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 10.7 µg/m³ less fine-particle pollution than Philadelphia right now
PM2.5 is 19.8 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 19.8/22 × 0.5 = 0.5 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 7.4 µg/m³ less fine-particle pollution than Philadelphia right now
Checking road route/District of Columbia/Some particle pollution/ PM2.5 21.1 µg/m³
PM2.5 is 21.1 µg/m³ here vs 27.2 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h out ≈ 21.1/22 × 0.5 = 0.5 here; 27.2/22 × 0.5 = 0.6 at home.A health-impact equivalence, not literal smoking.See how we work it out →
▼ 6.1 µg/m³ less fine-particle pollution than Philadelphia right now
Some particle pollutionLatest observation Jul 18, 5:00 p.m. EDT
Build-time readings shown
Air quality · Philadelphia
Phew. Twelve hours out here is roughlyPM2.5 here is 27.2 µg/m³.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.12 h outside ≈ 27.2/22 × 0.5 = 0.6 cigarettes.A health-impact equivalence, not literal smoking.See how we work it out →
That is the fine-particle pollution you'd breathe standing outside all day inPhiladelphia right now, turned into a number your body already understands.
A health-impact equivalence, not literal smoking: Berkeley Earth puts a full day at 22 µg/m³ of PM2.5 at about one cigarette.How we work this out
Why live rankings?
Smoke plumes are patchy and move with changing winds, terrain and weather. Nearby lakefront, coastal and higher-elevation places can be much clearer than Philadelphia, but no direction is reliably cleaner. That is why this list is recalculated from live PM2.5 readings every hour instead of publishing a fixed escape route. If everything within three hours is smoky, the rankings will say so. Sometimes the honest answer is to stay inside with a filter running.