EXCAVATION

BACKGROUND INFORMATION

Every year pople are killed or seriously injured while working in excavations. Many are killed or injured by collapses and falling materials, some are killed or injured when they contact buried underground services. Excavations need to be properly planned and carried out in accordance with a Permit to Excavate/Risk Assessment/Method Statement as appropriate.

---

HAZARDS

• Collapse of excavation sides.
• Materials falling onto persons in the excavation.
• People and vehicles falling into the excavation.
• Undermining nearby structures.
• Striking underground services.
• Hazardous atmosphere in the excavation.
• Flooding of excavation.

---

HEALTH AND SAFETY POINTS

• You must have the relevant Risk Assessment/Method Statement and Permit to Excavate.
• You must ensure that adequate support materials, access ladders, barriers (and traffic notices where appropriate) and readily available and used.
• Ensure tha tpublic services are marked and/or disconnected.
• If the excavation will undermine existing foundations then shoring (eg raking as flying shores) will probably be required.
• Barrier off the excavation zone to prevent access by chilren, consider blind people while excavating.
• Only use sound material for support work.
• A competent person should be in attendance at all times.
• Install timber as soon as excavation sides are trimmed. Do this only from ground level or from within supported ground.
• Never enter an unsupported excavation.
• Always ensure that supports are secure and props/wedges are tight.
• Look out for signs of over-stress in support work, damage from plant etc. When timber is used check for disease and defects such as dry rot and shakes.
• Check for water or soil creeping through support work.
• Ensure that pumping facilities are adequate.
• The atmosphere in some excavations may become contaminated or low in oxygen. Use a gas detector to monitor where this can occur.
• Keep spoil and materials back at least 1 meter from the edge of the excavation.
• Where persons may fall 2 meters or more into an excavation, guardrails must be placed around the edges. Bridges and gangways should be protected with guardrails and toeboards.
• Keep  vehicles away form the excavation with barriers, timber baulks etc.
• Ensure that there are adequate barriers/notices/warning lights in place.
• Use well anchored stops-blocks for dumpers, tipping wagons depositing fill material into an excavation.
• Only withdraw supports from a position of safety eg above ground or from supported ground.
• Give machine operators the best positive vision of work in progress.
• Mark, protect and support services exposed in excavation.
• The excavation must be inspected by a competent person before the start of each shift.
• Ensure that a record of all examinations is recorded in a register and signed by a competent person.

---

QUSTION TIME

• What things do you need to do before starting to dig?
• What problems can occur when digging close to buildings or roads?
• Where must excavation supports be installed from?

---

SAFETY REMINDER

Always excavate in accordance with the Permit to Dig, Risk Assessment or Method Statement. Support excavations from positions of safety. Ensure that excavations have been inspected prior to entry.