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
62
common PM2.5 hours out of 72 archive-eligible hours in this view
1. IIT Delhi
49 µg/m³
2. KNC
71 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
IIT Delhi
85%
of 62 archived PM2.5 hours ≤ 60 µg/m³
KNC
30%
of 63 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
Hauz Khas
Indian Institute of Technology Delhi
Current PM2.5
57 µg/m³
Average
49 µg/m³
Median
54.5 µg/m³
Lowest
30 µg/m³
6 Sept, 4:30 pm
Highest
61 µg/m³
7 Sept, 11:30 pm
Data coverage
62/71 eligible h · 87%
Denominator starts at this monitor's first archived observation in the selected archive window; later missing hours stay missing.
Reference monitor
IIT Delhi, Delhi - IITM
0.2 km from campus · IITM
Siri Fort
Kamala Nehru College
Current PM2.5
75 µg/m³
Average
70.8 µg/m³
Median
73 µg/m³
Lowest
52 µg/m³
6 Sept, 7:30 pm
Highest
91 µg/m³
7 Sept, 11:30 pm
Data coverage
63/72 eligible h · 88%
Denominator starts at this monitor's first archived observation in the selected archive window; later missing hours stay missing.
Reference monitor
Sirifort, Delhi - CPCB
0.6 km from campus · CPCB
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.