Primary definition
The phenomenon by which paper BALLOTS, such as optical scan and punched DOCUMENT cards, physically expand in conditions of high humidity, interfering with the ability of machines to read and feed them properly.
Also known asballot swelling · ballot card swelling · paper swelling · humidity-induced swelling · card swelling · ballot expansion · paper expansion
1 sources cited4 related termsReviewed Aug 9, 2026
— Electronic Voting GlossaryView source
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EVG
Carnegie Mellon University
The phenomenon by which paper BALLOTS, such as optical scan and punched DOCUMENT cards, physically expand in conditions of high humidity, interfering with the ability of machines to read and feed them properly.
Electronic Voting Glossary · 2024
Cite this term
Permanent URL · stable across revisions
Election Security Glossary. (2026). Swelling. In Election Security Glossary. Retrieved August 20, 2026, from https://electionsecurityglossary.com/glossary/swelling
Sources
1 cited · last checked Aug 9, 2026
01
Electronic Voting Glossary
Electronic Voting Glossary
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