Bristol, PA: what USGS's seismic model says

Bristol carries Seismic Design Category B under USGS's ASCE 7-16 model. Low seismic hazard. Code requires basic seismic detailing (bracing, connections) but no special structural system restrictions. Nationally, Bristol ranks above 58% of the 4,875 cities in this dataset for seismic hazard - the 58th percentile.

Bristol by the numbers

USGS's underlying values for Bristol: 0.11g peak ground acceleration, 0.194g at short period, 0.049g at 1 second. Within Pennsylvania alone, Bristol ranks 3 of 193 cities by seismic hazard - the 99th percentile in-state. Bristol has a population of about 9,982.

Retrofit economics for Bristol

A full earthquake retrofit typically runs $5,000-$10,000 nationally (around $7,000 typical), driven mainly by house size and foundation type, not by Pennsylvania specifically. California's Earthquake Brace + Bolt grant, which covers a large share of this cost, is a California-only program and does not apply in Pennsylvania.

Insuring against this, not just retrofitting

A Bristol homeowner cannot buy a standalone earthquake policy in most cases - it is added to an existing homeowners policy as an endorsement, so the place to start is a regular home-insurance quote.

Where Bristol's figures come from

Bristol's Category B and every number above trace to USGS's own ASCE 7-16 Design Maps service - see the methodology guide. See the category explainer for what Category B does and doesn't tell you about Bristol.