Dirty Air Report: Which 2025 F1 Races Were DRS-Trains vs Clean-Air Cruises?

If you’ve ever argued that “this race was impossible to overtake in” or “everyone was just driving alone,” this dataset finally puts numbers on that feeling.

For every driver in every 2025 Grand Prix, we measure how long they spent with a car ahead in these ranges:

• < 1.0s → “DRS range” (constant pressure / DRS-train territory)

• 1–2s → Heavy dirty air (close, but not always able to attack)

• 2–4s → Low dirty air (still in traffic, but less “stuck”)

• > 4s → Clean air (no car ahead within 4 seconds)

Important note: these totals are cumulative driver-seconds (added across all drivers), so the race totals look like “hours” because they represent the whole field combined.

The big picture (all races combined)

Across the season, the field spent roughly:

• 29.8% in <1s (DRS range)

• 17.4% in 1–2s (heavy dirty air)

• 18.8% in 2–4s (low dirty air)

• 34.0% in >4s (clean air)

So, on average, about two-thirds of the time (66%) drivers were still within 4 seconds of a car ahead — but that doesn’t mean the racing was good. A race can be “close” and still be a DRS train where nobody can pass.

1) Races with the MOST “<1 second” running (DRS-train magnets)

By total <1s time (whole field combined)

1. Bahrain GP — 11h 49m 42s total in <1s (35.5 min per driver avg)

2. Dutch GP — 11h 16m 15s (33.8 min/driver)

3. Qatar GP — 10h 38m 03s (31.9 min/driver)

4. Monaco GP — 9h 52m 44s (29.6 min/driver)

5. Emilia Romagna GP — 9h 51m 31s (29.6 min/driver)

By share of the race spent in <1s (this is the “train” indicator)

1. Qatar GP — 39.8% of all driver-time was <1s

2. Bahrain GP — 37.2%

3. Dutch GP — 36.4%

4. Emilia Romagna GP — 33.7%

5. Saudi Arabian GP — 33.6%

Conclusion: If you want to label races as “DRS-train heavy,” Qatar, Bahrain, Dutch, Imola, Saudi are your headline tracks from this dataset. High <1s share usually means constant chasing, not necessarily overtaking.

This shows hoe many seconds each driver had a car within a second ahead of him!

2) Races with the MOST clean air (>4 seconds ahead)

By clean-air share (the “spread-out” indicator)

1. Spain GP — 44.4% clean air (avg 39.6 min per driver in clean air)

2. Hungarian GP — 39.8%

3. Las Vegas GP — 39.7%

4. USA GP — 39.6%

5. Italian GP — 38.6%

Conclusion: Spain stands out massively. It’s the most “everyone got separated” race in your dataset by a clear margin.

Driver	Seconds spent in Clean Air
VER	74201
PIA	68405
NOR	66611
LEC	57191
RUS	49900
HAM	46417
TSU	41242
ANT	35850
LAW	35181
OCO	34788
ALB	34335
HUL	34128
HAD	33750
GAS	33182
STR	32201
BEA	30800
SAI	30361
ALO	30177
BOR	29073
COL	28272
DOO	4647
Total	830715

3) The “traffic index”: races where drivers spent the most time within 4 seconds (<4s)

This combines <1s + 1–2s + 2–4s, i.e. “you had someone ahead close enough to matter.”

Top 5 by traffic share:

1. Bahrain GP — 74.7% of the time in traffic

2. Japanese GP — 72.7%

3. Dutch GP — 72.5%

4. Qatar GP — 72.1%

5. Emilia Romagna GP — 71.1%

Bottom 5 (most “free air” overall):

• Spain GP — 55.6%

• Hungarian GP — 60.2%

• Las Vegas GP — 60.3%

• USA GP — 60.4%

• Italian GP — 61.4% in traffic

Conclusion: Bahrain is the king of constant proximity, while Italian GP is the king of gaps.

4) Heavy dirty air (1–2s) vs low dirty air (2–4s): what kind of “traffic” was it?

Highest 1–2s share (tight but not always attacking)

1. Australian GP — 22.1%

2. Japanese GP — 21.3%

3. Saudi Arabian GP — 20.4%

4. Emilia Romagna GP — 19.6%

5. British GP — 19.4%

Highest 2–4s share (close-ish, but more “managed gaps”)

1. Japanese GP — 23.3%

2. Mexico GP — 22.2%

3. British GP — 21.2%

4. Chinese GP — 21.0%

5. Azerbaijan GP — 21.0%

Conclusion:

• Australia/Japan/Saudi = lots of “almost attacking but not quite” running (1–2s).

• Japan/Mexico/Britain = lots of “in-range but not nose-to-tail” running (2–4s).

• Japan appears in both lists → it was “busy” at multiple distances, not just one type of traffic.

5) Fun driver-level notes

The “I saw nobody all day” club (100% clean air)

These are races where the driver recorded 0s in all traffic bins and all time in clean air:

• PIA — Dutch GP (5900.581s clean air)

• NOR — Mexico GP (5869.780s)

• VER — USA GP (5631.218s)

• VER — Azerbaijan GP (5595.321s)

That’s a perfect “dominance / isolation” storytelling hook.

Who lived in DRS trains all season?

Fernando Alonso DRS Train

Across the season totals, the biggest <1s guys are mostly midfield runners — exactly what you’d expect:

• OCO, TSU, GAS, ALB, SAI, ALO near the top for total time in <1s

Meanwhile, the clean-air kings are your front-runners:

• VER has the highest clean-air share overall (~58.9% of his time)

What this data really tells you?

• A race can be “close” in lap-time terms but still be hard to pass. High <1s share often means DRS trains (Qatar is the poster child here).

• A race can look calm because everyone is in clean air, but that usually means gaps formed early and stayed (Spain is the standout).

• The best “race type” fingerprint is the mix:

  • High <1s + high traffic → train-heavy, pressure without movement

  • High 1–2s → constant dirty-air management, strategic pace control

  • High clean air → spread-out, “drive your own race” territory