---
title: "Blast Radius — Definition | FourSight Glossary"
url: https://foursight.cloud/glossary/blast-radius
description: "The scope of users, systems, or data affected by an incident. \"Limit the blast radius\" means contain the failure to as small a group as possible."
lang: en
---

Back to glossary: https://foursight.cloud/glossary

Incidents & On-Call

# Blast Radius

The scope of users, systems, or data affected by an incident. "Limit the blast radius" means contain the failure to as small a group as possible.

Source

- AWS Well-Architected — Reliability Pillar — Limit the scope of impact (https://docs.aws.amazon.com/wellarchitected/latest/reliability-pillar/welcome.html)

## Related terms

Incident

An unplanned event that disrupts service or threatens to.
https://foursight.cloud/glossary/incident

Severity (SEV-1 to SEV-4)

A standardized scale for how serious an incident is.
https://foursight.cloud/glossary/severity

Incident Commander (IC)

The single person who owns coordination of an incident end-to-end.
https://foursight.cloud/glossary/incident-commander

Tech Lead (during incident)

The engineer actively diagnosing and fixing the problem during an incident.
https://foursight.cloud/glossary/tech-lead

Comms Lead

Owns customer-facing communication during an incident — status page updates, in-product banners, support te…
https://foursight.cloud/glossary/comms-lead

On-Call Rotation

A scheduled rotation of engineers who are responsible for responding to alerts outside business hours.
https://foursight.cloud/glossary/on-call-rotation

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