.map-toolbar,.map-stage,.freshness-bar,.map-side{display:none !important}

Act now — no map needed

The interactive map needs JavaScript to shade live conditions for your country. You don’t need it to act — these vetted, globally relevant organisations are one click away.

Test your home for radon (a $15-30 kit, posted) · opens who.int → A short-term radon test kit is the only way to know whether your home has a problem. Place it on the lowest lived-in level for 2 to 7 days, return it for lab analysis, and the lab posts back a value in Bq/m3 or pCi/L. The WHO recommends action above 100 Bq/m3; many national programs use 200 or 300 Bq/m3.
Read the WHO Handbook on Indoor Radon · opens who.int → The single canonical reference for indoor radon as a public-health topic. Published by the WHO with the input of every national radiation protection program; chapters cover measurement, mitigation, communication, and the dose-response evidence in plain (if formal) English.
If you draw from a private well, test it · opens who.int → Municipal water systems are tested by their operators; private wells are not. If your home draws from a private well, an annual test for the named contaminants relevant to your geology (arsenic, radon, radium, uranium, nitrates, bacteriological) is the only way to know what you are drinking. National environmental agencies maintain lab lists.
Read why radon and smoking multiply each other's risk · opens publications.iarc.fr → Among people who never smoked, radon at typical residential exposure levels is responsible for a small but measurable share of lung-cancer cases. Among people who smoke, the same radon exposure raises lung-cancer risk by roughly an order of magnitude more, because the two damage pathways multiply rather than add. The IARC, WHO, and US Surgeon General have each documented this.
If you smoke, the same kit becomes higher-leverage with cessation support · opens who.int → Radon testing and a smoking-cessation conversation belong on the same to-do list because the risks interact. Named national cessation programs are free in most countries; the WHO maintains a quit hub with country-by-country contact lines.

Want today’s single pick across every topic? See actsmall.org/today. For more sources, browse ActSmall · Ground.

Ground Map

Tap any country — see (where national surveys exist), adult smoking prevalence, drinking-water access gaps, and one concrete next step that fits the place. Refreshed once a day from World Bank Open Data and hand-authored country-level radon baselines from named national radiation protection agencies. Open data only, polite cadence, no scraping.

Opens on a country where surveyed radon and smoking prevalence both stand out. Use search or the worst-list to explore your own region.

Loading live indicators…

Act now — what you can do

These work no matter where you live. Click a country on the map and the regional sources here re-sort to match.

Top by indicator

Top 12 countries on the active indicator. Click a row to fly there and see actions.

How this map works

Country shading shows live data fetched once a day:
- Joint radon and smoking risk - a computed product of the radon classification (elevated/moderate/low/unsurveyed) and adult smoking prevalence. Higher = stronger case for the paired test-and-quit action.
- Indoor radon (national arithmetic mean) - average indoor radon concentration in /m3 from named national radiation protection agencies (UKHSA, , BfS, SURO, SSM, STUK, IRSN, Health Canada, ARPANSA, and others). Unsurveyed countries are not shaded.
- Adult tobacco use prevalence (%) - World Bank SH.PRV.SMOK, sourced from Global Health Observatory.
- Population without (%) - computed from World Bank SH.H2O.SMDW.ZS (/ Joint Monitoring Programme).
Click anywhere to see one concrete next step. The recommender derives a country profile from the indicators above and surfaces a use-case-matched action with named, citable organisations.
Freshness. Indicators are pulled on a daily schedule, normalised into a single tiny payload, and served to every visitor. Your browser only ever talks to our own server for the data. We never scrape; we only consume documented public APIs at their published cadence.
No accounts. No tracking. No upload. Outbound calls from the browser: our own server (live data + borders) and OpenFreeMap (basemap).

Sources: country borders — Natural Earth (public domain); basemap — OpenFreeMap & OpenStreetMap contributors (ODbL); adult tobacco use prevalence and drinking-water access — World Bank Open Data (CC BY 4.0; SH.PRV.SMOK from Global Health Observatory, SH.H2O.SMDW.ZS from ); indoor radon baselines — Handbook on Indoor Radon and named national radiation protection agencies (UKHSA, US , BfS, SURO, SSM, STUK, IRSN, Health Canada, ARPANSA, and equivalent bodies); arsenic-affected aquifer list — Arsenic fact sheet and named regional surveys; rendering — MapLibre GL JS (BSD-3); action catalog assembled from public materials of named organisations: the World Health Organization, the , , the US , UKHSA, the AARST, Health Canada, IRSN, BfS, the , , Image Gently, and Choosing Wisely.

National figures hide local realities. Where a country has no comprehensive national radon survey, we display “no current reading” rather than guessing - that gap itself is sometimes the action.