Confined space

From GAWDAwiki

A confined space is an enclosed or small space often without adequate ventilation. If it becomes filled with an inert or unreactive gas, it's an area of potential hazard from asphyxiation. It's also an area of potential explosion if filled with a flammable or explosive gas mixture. ^[1]

References

1. http://www.bocindustrial.co.uk/bocindustrial/technical/glossary/a.asp