TA-DL-05 · Drainlaying
Excavation and Trenching (incl. Near Assets) Task Analysis
Excavating trenches for sewer and stormwater drains and pit installation - service location, potholing near assets, ground support, entry and egress, dewatering, backfill and reinstatement.
What you get
One editable Word document covering excavation and trenching (incl. near assets) for Drainlaying: the task broken into steps, the hazards at each step, the controls, and a 5 by 5 risk matrix with residual ratings. Site fields and a crew sign-on are built in.
A Task Analysis is also known as a JSA (Job Safety Analysis) or JSEA. It covers each step of the job, the hazards and the controls.
The steps and hazards it covers
| Step | Hazards |
|---|---|
| Plan, prepare and confirm competency | Workers without the required training, competence or authorisation performing the task - incidents arising from lack of skill, competency or authorityDefective or unsafe plant, powered equipment, leads or attachments failing in useWorking on other people's sites, occupied premises or around the public |
| Locate services and design the excavation | Striking unidentified underground services - electrocution, gas release or floodingOverhead powerlines contacted by the excavator boom - electrocution |
| Set up exclusion zones and establish the work area | Unauthorised approach or plant interaction with the open excavation |
| Pothole and excavate near located services | Mechanical bucket strike on power, gas or water - electrocution, explosion or floodingGas struck or smelt - fire or explosionElectrical cable struck - electrocution at the machine or in the trench |
| Excavate the trench and install ground support | Trench wall collapse or engulfment - fatalityWater ingress or wet weather - wall instability, collapse or drowning |
| Operate plant near the open trench | Plant or worker falling into the trench; struck-by plant |
| Excavate near existing structures and retaining walls | Removing the ground that supports a retaining wall, footing or structure - sudden collapse of the wall and the earth it retains onto workers in the excavation |
| Enter and exit the trench | No safe access or egress - entrapmentOxygen-deficient or toxic atmosphere in deep or contaminated trenches |
| Backfill, reinstate and demobilise | Workers struck or caught during backfill; dust and noiseOpen trench left unsafe; trips and falls after hours |
Each hazard comes with its control measures, an initial and residual risk rating and the person responsible, ready to check against your job.
How to use it
Read it against the actual job. Delete the hazards that are not there, add the ones that are, fill the site fields, then brief the crew and get every name on the sign-on. A document nobody has read is a piece of paper. One the crew helped finish supports worker consultation and records the agreed work method. Engagement under HSWA ss58 to 59 is an ongoing process of seeking and considering workers’ views, so the signed page is evidence of part of it rather than the whole duty.
About Drainlaying Task Analysis
This is one of the Task Analysis documents written for Drainlaying crews. The trade covers trench excavation and shoring, foul and stormwater, connections, chambers and confined spaces, reinstatement.
See every Drainlaying document, or the whole pack for $199.99. Need 5 or more templates from this trade? The pack costs less than buying them individually, and saves $49.96 at 5.
Where it sits in the law
New Zealand does not require a document of this name. The duty is to manage risk so far as is reasonably practicable (HSWA s36) and to engage workers on it (ss58 to 59). Use a Task Analysis to plan the work, identify the hazards and communicate the controls to your crew. That is also how you evidence both duties.
WorkSafe names “a task analysis, safe work method statement (SWMS), job safety analysis or equivalent planning document” as the same thing done under different headings, and Site Safe titles one of its own SSSP forms “Task Analysis (TA) and Safe Work Method Statement (SWMS)”. So if the paperwork you have been sent asks for a TA, a SWMS or a JSA, this is the document it means, written to the Health and Safety at Work Act 2015. Only the name changes; the hazards, controls and ratings are the same either way.
Where this sits in your SSSP
A Site-Specific Safety Plan (SSSP) covers the whole job: who is on site, how hazards get reported, what happens in an emergency. A Task Analysis covers one task inside it. They are not the same document. Site Safe’s SSSP pack runs to ten forms, and the Task Analysis is Form 10, filed behind the plan itself.
So a main contractor who asks which SSSP pack you are using, and then asks for a TA covering excavation and trenching (incl. near assets), has asked you for two separate things. This is the second one. Keep it with your SSSP for the job and bring it to the pre-start briefing, because the value is in the crew having read it before the work starts.
Same task, other trades
This task exists in other trades too, and each edition is written for that crew. Compare all 3, or go straight to Electrical, Plumbing.