RENGASREPOPractical tyre intelligence
Open Research DatasetCC BY 4.0DOI: Pending (Zenodo)AI-assisted

Road safety dataset.
Open statistics 2015–2026.

Municipal collision severity, vehicle fleet normalization, and wildlife impact across 307 Finnish municipalities. Based on 39,594 verified injury collisions and 11 years of Open-Meteo & FMI climate time series.

Open Data Package & Replication

Full 307 municipality master dataset precomputed with Koneisto Core Go Turbine.

Download JSON (403 kB)DOI pending (Zenodo)
BibTeX Citation
@dataset{pelkonen_2026_road_weather,
  author       = {Pelkonen, Tommi},
  title        = {{Finnish Road Weather and Traffic Safety Index 2015--2026: Municipal Collision Severity, Vehicle Fleet Normalization, and Wildlife Impact Dataset}},
  year         = 2026,
  month        = sep,
  publisher    = {Zenodo},
  version      = {1.0.0},
  url          = {https://rengasrepo.fi/tutkimus},
  note         = {DOI pending (Zenodo) / Open Science Dataset (CC BY 4.0)}
}
Python Replication Script
# Suomen tiesää- ja onnettomuusdatan toistettavuusanalyysi (Python)
import pandas as pd
import json, urllib.request

# 1. Haetaan 307 kunnan master-aineisto
url = "https://rengasrepo.fi/data/rengaskeli_kuntatilastot_master.json"
req = urllib.request.urlopen(url)
data = json.loads(req.read().decode('utf-8'))

# 2. Muunnetaan kunnat dataframeksi
kunnat = pd.DataFrame.from_dict(data['kunnat'], orient='index')

# 3. Tarkastellaan kolaritiheyttä suhteutettuna 1 000 rekisteröityyn autoon
karkikunnat = kunnat.sort_values(by='kolarit_per_1k_autoa', ascending=False)
print("Top 10 kuntaa - henkilövahinkokolarit per 1 000 autoa (11 v keskiarvo):")
print(karkikunnat[['kunta', 'henkiloautot_liikenteessa', 'kolarit_per_1k_autoa', 'kolarit_per_10k_asukasta', 'kuolemanriski_pct']].head(10))

# 4. Koko maan keliolosuhteet
print("\nKoko maan kelijakauma henkilövahinkokolareissa:")
for keli, pct in data['koko_maa_yhteenveto']['keli_jakauma'].items():
    print(f"  {keli}: {pct} %")

Five Municipal Risk Archetypes in Finland

When collision figures are normalized per 1,000 cars and per capita, municipal traffic risks diverge sharply.

Highest Collision Ratio / Car · Highway 4

1. Transit Highway Hubs

Representative municipalities: Heinola, Joutsa, Ii, Lapua

Collisions / 1k cars
1,60 – 2,10
Fatality rate
6,5 – 8,0 %

Traffic Risk Anatomy

Heavy transit logistics, highway speeds and narrow passing zones relative to small local vehicle fleet.

Statistical Precaution & Fitting Week

High-speed directional stability and a 10-meter shorter stopping distance save lives. Never enter highway autumn on under 4 mm tread.

Statistical winter fitting: Week 43 (late October)

National Road Weather & Road Type Evidence (11 Years)

All 39,594 injury collisions recorded by police in Finland (2015–2025) categorized by surface condition and road classification.

Road Surface Conditions (All Finland)

ConditionAccidentsShare
Bare, dry23 60559,6 %
Bare, wet (rain)7 41718,7 %
Icy (black ice / pack)4 25310,7 %
Snowy2 3746,0 %
Slushy (slush-planing)1 0492,6 %
Winter ruts bare6631,7 %

Icy roads cause almost twice as many injury collisions as snowy roads (10.7% vs 6.0%).

Road Classification & Fatality Rate

Road ClassInjuriesDeathsFatality %
Private / Lake cottage roads1 8871799,5 %
State highways18 9721 4367,6 %
Urban municipal streets13 8353572,6 %

⚠️ Private rural roads carry nearly four times higher fatality probability per collision than urban streets.

2020 Road Traffic Act Impact

Oct–Nov Early Winter Collisions: -33.3%

Transitioning from fixed calendar enforcement (1 Dec) to weather-dependent requirement (1 Nov) coincided with modern vehicle safety tech (ADAS, AEB) dropping autumn injuries from 769.0 to 512.6/yr. However, peak day collision spikes on the exact first icy morning have sharpened.

Natural Experiment: WRC Rally Finland

Jyväskylä August Collisions (2018–2024)

When Rally Finland was cancelled in August 2020 due to Covid, Jyväskylä recorded a record-low 6 injury accidents (vs. 15 in August 2018). Normal rally years see an 80–114% surge in August collisions compared to July due to massive regional spectator traffic.

Municipal Comparison

307 Municipalities Safety Ranking 2026

Search any Finnish municipality, explore top lists of safest towns, highway hubs, and cottage road fatality risks.

Open Municipal Ranking
Knowledge Hub

Thematic Evidence Articles

Detailed investigations on first snow physics, lake cottage gravel dangers, and driver risk homeostasis.

Browse All Articles