41074

The annual rate of fatal road crashes per 100,000 residents, pooled over a ten-year window.

A rate per resident population. Where a ZIP has too few residents for the rate to be reliable — about 30% of US ZIPs — no value is published rather than an unstable one; those ZIPs are absent from this comparison, not counted as crash-free.

The lead level at the 90th percentile of tap-water samples reported by the public water systems serving this ZIP, in parts per billion — the EPA requires action above 15 ppb.

Measured from EPA records for the public water systems that serve this ZIP. Households on private wells — roughly 30% of the US population — are not covered by this measure, and this figure says nothing about their water.

The share of residents served by public water systems where PFAS — man-made “forever chemicals” that build up in the body and environment instead of breaking down — were detected in EPA testing.

Measured from EPA records for the public water systems that serve this ZIP. Households on private wells — roughly 30% of the US population — are not covered by this measure, and this figure says nothing about their water.

The number of public-transit stops inside this ZIP’s boundary, per 1,000 residents.

Counted from establishments located inside this ZIP’s boundary, so one just across the line is not counted. Where a ZIP has too few residents for the density to be reliable, no value is published rather than an unreliable one.

The EPA’s modeled screening score for industrial chemical releases, weighting the amounts released by their toxicity and how many people live nearby — a relative comparison score, not a measured exposure.

The share of this ZIP’s land area inside FEMA’s 1%-annual-chance floodplain — the “100-year” flood zone, where flooding has about a 1-in-100 chance in any given year.

Measured from FEMA’s mapped flood panels. Where a panel has not been mapped, no value is published for that ZIP — those ZIPs are absent from this comparison rather than counted as unexposed.

The modeled share of residents exposed to average road, rail, and aviation noise at or above 55 decibels — a noticeable background presence.

The EPA’s modeled estimate of added lifetime cancer risk from breathing outdoor air toxics, in cases per million people exposed over a lifetime.

The number of full supermarkets inside this ZIP’s boundary, per 1,000 residents.

Counted from establishments located inside this ZIP’s boundary, so one just across the line is not counted. Where a ZIP has too few residents for the density to be reliable, no value is published rather than an unreliable one. ZipVitals’s food-access signal is derived from these in-ZIP densities — it is not USDA’s food-desert designation, which measures distance to the nearest supermarket. Where a leg is missing, a ZIP reads “not determinable,” never “not a food desert.”

The number of street intersections per square mile — a standard street-connectivity measure; denser networks correlate with more walkable neighborhoods.