Trench shoring guidelines for New Zealand
In New Zealand, Health & Safety Regulations require notification be given to the HSE inspector if trenches are deeper than 1.5m.
Requirements and options for safe trenching are given in the Department of Labour Approved Code of Practice for Safety in Excavation and Shafts for Foundations.
Excavations greater than or equal to 1.5m deep must be shored unless:
(a) The face is cut back to a suitable slope or benched or
(b) A registered engineer certifies that safety precautions taken are adequate
More information can be found on the Trench Shoring NZ’s website.