Steel trench sheeting is positioned and driven pneumatically to final depth, with toms and walings placed as soil is removed; adjustable jacks or struts are more efficient than timber (Figure 14). It is lighter than sheet piling and may be driven with hand-held pneumatic or electric vibrating hammers, which carries a very high risk of manual handling injury and of cuts from sharp metal, and these risks should be dealt with before driving begins. Projections under the jackhammer anvil should be removed to protect the driving cap and operator. If workers may be exposed to noise above the exposure standard while driving, noise exposure must be controlled. A competent person should design steel shoring and trench lining gear (see AS 4744.1-2000).
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.