# Armstrong limit

> altitude above which water boils at human body temperature, making it absolutely impossible for humans to survive unpressurized; approx. 18–19 km above sea level

**Wikidata**: [Q2739914](https://www.wikidata.org/wiki/Q2739914)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Armstrong_limit)  
**Source**: https://4ort.xyz/entity/armstrong-limit


## References

1. Freebase Data Dumps. 2013
2. Quora