Loading the owned archive and shared-hour comparison…
Campus comparison · owned archive
Compare two to five campus-linked reference monitors over the same archived hours. Current readings remain visible, while the historical ranking uses only PM2.5 hours shared by every selected reference monitor.
Official archive-first current layer · The page renders from Delhi Air Health's hourly CPCB-linked archive first, so a slow upstream API cannot hold the interface open. Source timestamp and monitor provenance stay attached to every value.
Owned archive · campus comparison
Ranking uses only archived hours where every selected campus reference monitor has a PM2.5 value. That keeps missing data from quietly giving one campus an easier comparison window.
Selected 2 of 5
The URL updates as you change this comparison.
Archive boundary
Archive began 6 Sept 2026, 4:00 pm. The requested 7-day period extends earlier than the dataset, so the chart and coverage denominators begin at the first archived hour instead of counting pre-archive time as missing.
Shared-hour ranking
30
common PM2.5 hours out of 72 archive-eligible hours in this view
1. LHMC
39.7 µg/m³
2. Hansraj
84.2 µg/m³
Lower here means a lower average PM2.5 at the linked reference monitor across the exact same archived hours. It is not a long-term health ranking of the campuses.
Threshold context
LHMC
100%
of 44 archived PM2.5 hours ≤ 60 µg/m³
Hansraj
27%
of 49 archived PM2.5 hours ≤ 60 µg/m³
These are concentration thresholds for exploring the archive, not official AQI categories and not exposure limits.
Side-by-side history
Connaught Place area
Lady Hardinge Medical College
Current PM2.5
32 µg/m³
Average
36.3 µg/m³
Median
33.5 µg/m³
Lowest
18 µg/m³
6 Sept, 4:30 pm
Highest
49 µg/m³
7 Sept, 11:30 pm
Data coverage
44/71 eligible h · 62%
Denominator starts at this monitor's first archived observation in the selected archive window; later missing hours stay missing.
Reference monitor
Mandir Marg, Delhi - DPCC
1.1 km from campus · DPCC
Malka Ganj / North Campus
Hansraj College
Current PM2.5
62 µg/m³
Average
75 µg/m³
Median
74 µg/m³
Lowest
53 µg/m³
6 Sept, 10:30 pm
Highest
103 µg/m³
7 Sept, 10:30 pm
Data coverage
49/72 eligible h · 68%
Denominator starts at this monitor's first archived observation in the selected archive window; later missing hours stay missing.
Reference monitor
Chandni Chowk, Delhi - IITM
3.0 km from campus · IITM
Interpretation boundary
This compares the nearby monitoring stations associated with each campus, not personal exposure and not air inside classrooms, hostels or hospitals. Campuses that share one physical reference monitor are explicitly marked; duplicated station data are not evidence of an independent campus difference. Pre-archive time is never coded as missing. Coverage is computed only over archive-eligible hours, and the ranking uses only PM2.5 hours shared by every selected reference monitor.