An excavation is any hole or trench dug into the ground as part of construction or utility work. Some excavations are knee deep, but many are deeper. They do not need to be deep before becoming a serious risk or a confined space.
Every year deaths and injuries occur due to excavations collapsing, or workers being overcome by poisonous gases or striking live services.
Many accidents happen when the excavation appears to be in good condition, with no obvious hazards.
A cubic metre of soil can weigh over a tonne (1,000 kg). A human body cannot support that much weight.
Even a shallow excavation can easily collapse onto you.
It can crush your legs, hips or chest and prevent you breathing, within seconds.
Collapse is silent and without warning.