https://www.faa.gov/air_traffic/separation_standards
Separation Standards Analysis Branch | Federal Aviation Administration
Separation Standards Analysis Branch
separation standardsfederal aviationanalysisbranchadministration
https://www.gov.uk/government/publications/regulatory-article-ra-3228-separation-standards
Regulatory article (RA) 3228: separation standards - GOV.UK
RA covering separation standards which provide the means by which controllers can control safely, under differing conditions.
separation standardsregulatoryarticleuk