Standards

Verified

Non User Serviceable Failure

Primary definition

Functional failure that requires the manufacturer or highly trained personnel to repair.

Also known asnon-user-serviceable fault · non-user-serviceable malfunction · non-user-serviceable error · NUF · non-serviceable failure · factory-serviceable failure · manufacturer-serviceable failure · non-user-repairable failure · non-user-repairable fault
1 sources cited4 related termsReviewed Aug 10, 2026
NIST Election GlossaryView source
People also ask

What is non user serviceable failure?

The term Non User Serviceable Failure refers to a failure that cannot be repaired or serviced by ordinary users or election workers and therefore requires authorized technical maintenance, replacement, or vendor support. It gives election, security, legal, or technical readers a specific label for the concept rather than a broader everyday meaning.

How does non user serviceable failure work in a voting system?

In practice, Non User Serviceable Failure is applied to the technical or security purpose captured by its definition: a failure that cannot be repaired or serviced by ordinary users or election workers and therefore requires authorized technical maintenance, replacement, or vendor support. Organizations combine that function with documented procedures, authorized access, testing, monitoring, and controls appropriate to the system.

Why does non user serviceable failure matter for election verification?

Understanding Non User Serviceable Failure matters because the concept can affect security, reliability, auditability, or trusted operation. In this glossary context, it refers to a failure that cannot be repaired or serviced by ordinary users or election workers and therefore requires authorized technical maintenance, replacement, or vendor support.

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NIST

Functional failure that requires the manufacturer or highly trained personnel to repair.

NIST Election Glossary · 2024

Cite this term

Permanent URL · stable across revisions
Election Security Glossary. (2026). Non User Serviceable Failure. In Election Security Glossary. Retrieved August 21, 2026, from https://electionsecurityglossary.com/glossary/non-user-serviceable-failure

Sources

1 cited · last checked Aug 10, 2026

01

NIST Election Glossary
NIST Election Glossary

Single-source

View source

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