Engineering English
Factor of Safety
Civil Engineering · Mechanical Engineering · Last updated: July 30, 2026 · How this entry was written
Definition: A ratio that compares the available strength of a soil or structure to the applied load or stress. In geotechnical engineering, it is used to ensure stability in slopes, foundations, and retaining walls.
Example in context
“A minimum factor of safety of 1.5 is often required for slope stability analysis under static loading conditions.”
“Statik yükleme koşullarında şev stabilite analizi için genellikle en az 1.5 güvenlik faktörü gerekir.”
Where engineers use it
The factor of safety is determined in slope stability, bearing capacity, and earth pressure calculations. Engineers apply it to account for uncertainties in soil properties and loading.
Synonyms: safety factor, FoS
In Mechanical Engineering
The ratio of a component's failure strength to the maximum expected working stress, used to cover uncertainties in loads, materials, and analysis.
“The lifting hook was designed with a factor of safety of five because the actual service loads and impacts are hard to predict.”
Practice: can you use “Factor of Safety” at work?
A proposed cut slope in a highway project shows a factor of safety of 1.2 from limit equilibrium analysis. The client wants to reduce costs by accepting a lower value. Justify the required minimum factor of safety.
Show a model answer
“What factor of safety would you recommend for this embankment and why?”
“Factor of Safety” in 21 languages
| English | Factor of Safety |
|---|---|
| Turkish | güvenlik faktörü |
| French | facteur de sécurité |
| German | Sicherheitsfaktor |
| Spanish | factor de seguridad |
| Chinese | 安全系数 |
| Arabic | عامل الأمان |
| Portuguese | fator de segurança |
| Russian | коэффициент запаса |
| Japanese | 安全率 |
| Italian | fattore di sicurezza |
| Vietnamese | hệ số an toàn |
| Hindi | सुरक्षा का गुणांक |
| Thai | ค่าความปลอดภัย |
| Indonesian | faktor keamanan |
| Korean | 안전율 |
| Bengali | নিরাপত্তার গুণক |
| Dutch | veiligheidsfactor |
| Swedish | säkerhetsfaktor |
| Finnish | varmuuskerroin |
| Ukrainian | коефіцієнт запасу |
Frequently asked questions
What does Factor of Safety mean in engineering?
A ratio that compares the available strength of a soil or structure to the applied load or stress. In geotechnical engineering, it is used to ensure stability in slopes, foundations, and retaining walls. In Civil Engineering, the term carries a usage-frequency rating of 10/10 in the Engineering English library.
How do you pronounce Factor of Safety?
Factor of Safety is pronounced /ˈfæktər əv ˈseɪfti/ (IPA). The Engineering English app plays audio for the term and checks your pronunciation with speech recognition.
How is Factor of Safety used in a sentence?
Example from an engineering context: “A minimum factor of safety of 1.5 is often required for slope stability analysis under static loading conditions.”
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