TL;DR
A shutdown survey is precision dimensional and as-built measurement carried out while a plant is offline during a planned shutdown, turnaround or outage, capturing the exact position, alignment and geometry of equipment so replacement parts, modifications and tie-ins fit first time when the plant restarts. It is the survey that protects the critical path of a multi-million-dollar outage.
Key takeaways
- A shutdown survey is dimensional, alignment and as-built measurement performed inside a maintenance outage window, typically to ±0.5–2 mm, so that new spools, equipment and structural steel fit on first installation rather than being re-worked on the critical path.
- It is time-critical work: an Australian processing-plant shutdown can cost AUD $500,000–$2 million per day in lost production, so surveys are scheduled to the hour and crews routinely work 12-hour day and night shifts to fit the window.
- Core deliverables are captured with survey-grade total stations (Leica TS16/TS60, Trimble S9) and laser scanners (Leica RTC360, FARO Focus, Trimble X7), producing point clouds, as-built CAD and clearance reports referenced to a stable local plant grid rather than GDA2020/MGA2020.
- Australian operations from the Pilbara iron-ore plants and Worsley/Pinjarra alumina refineries to Hunter Valley and Bowen Basin coal handling rely on shutdown surveys for equipment replacement, brownfield tie-ins and clash detection.
- A typical shutdown survey scope costs AUD $8,000–$40,000 depending on duration, shift pattern and deliverables — a fraction of the cost of a single day of slipped restart.
What is a shutdown survey?
A shutdown survey is a specialist industrial surveying service delivered during a plant shutdown — also called a turnaround (TAR) or outage — when equipment is stopped, isolated and made safe so it can be inspected, repaired, replaced or modified. The surveyor captures the precise geometry of the plant while it is accessible and cold, producing the dimensional data that maintenance, engineering and fabrication teams need to complete the work correctly within the outage window.
Definition: shutdown survey A shutdown survey is the dimensional control, alignment and as-built measurement of plant and equipment carried out during a planned or unplanned outage, capturing exact positions, levels and clearances to engineering tolerance so that replacement components, structural modifications and tie-ins are manufactured and installed to fit first time.
The defining constraint of a shutdown survey is not accuracy — most ISS work is accurate by default — it is time. A shutdown is a window measured in hours and days, during which a plant earning hundreds of thousands of dollars a day sits idle. Every survey task competes for the same access, the same isolations and the same critical path as mechanical, refractory and structural trades. The surveyor's job is to extract complete, correct data fast, often at night, in a confined and congested plant, and turn it around quickly enough that fabrication or installation can proceed before the window closes.
That is what separates shutdown surveying from ordinary as-built work: the same instruments and the same tolerances, but executed against an unforgiving clock and an environment that exists for only a few days a year.
Key facts about shutdown surveys
- Shutdown surveys are commonly executed in 12-hour shifts around the clock, because the outage window is fixed and survey access often opens only once isolations and scaffolding are complete.
- Typical positional accuracy is ±0.5–2 mm for equipment alignment and as-built tie-ins, captured against a stable local plant grid so that relative geometry — not earth position — governs the fit.
- Laser scanning has become the default capture method for congested plant, with a Leica RTC360 recording up to 2 million points per second to document an entire process area in a single shift (Leica Geosystems, 2023).
- The single most valuable shutdown deliverable is often a clearance and clash check: confirming that a new vessel, conveyor or pipe spool will physically fit the existing steel before it is fabricated.
- Shutdown surveys integrate with dimensional control and as-built survey work, because the same outage that exposes equipment for measurement is also when alignment and as-built records are most easily updated.
How a shutdown survey works
A shutdown survey is planned weeks ahead and executed in a compressed window, frequently overnight. The five-step process below is the standard methodology ISS uses on Australian mining, processing and heavy-industry outages.
The shutdown survey process
Pre-shutdown scoping and control: Before the outage, the surveyor walks the scope with the shutdown planner, establishes a stable local control network of permanent reference marks around the work area, and ties it to the existing plant grid. This network is the fixed framework every measurement during the outage refers back to, and it must survive scaffolding, crane lifts and trade traffic.
Baseline and demolition capture: As soon as access opens, the surveyor records the as-found condition — the exact positions, levels and clearances of equipment to be removed or modified — often by laser scanning the whole area so nothing is lost once components come out.
Setout and installation control: Replacement equipment, structural steel and tie-in points are set out from the control network so that fitters and riggers install to design position. New baseplates, anchor bolts and flange faces are checked against tolerance before the load is dropped or grouted.
As-built and clearance verification: Once installed, the new work is measured back to confirm it sits where it should and that all clearances are met. A point-cloud or total-station as-built becomes the permanent record of what was actually built during the outage.
Rapid reporting: Deliverables — alignment results, clearance reports, as-built CAD, point clouds — are issued fast, often shift-by-shift, so the next decision on the critical path can be made without waiting for the plant to restart.
Key point: The most expensive moment in any shutdown is a part that does not fit. A shutdown survey earns its fee by catching that on the screen — in a clash check or a clearance report — instead of on the critical path, with a crane hanging and the restart slipping.
Shutdown survey vs standard as-built survey
A shutdown survey uses the same instruments and tolerances as routine survey work, but the operating constraints are entirely different. Understanding which you need governs how the work is scoped and priced.
| Aspect | Shutdown survey | Standard as-built survey | Operational alignment survey |
|---|---|---|---|
| Plant state | Offline, isolated, time-boxed | In service or under construction | Often running (hot) or briefly stopped |
| Accuracy | ±0.5–2 mm | ±2–5 mm | ±0.1–0.5 mm |
| Driving constraint | Outage window and critical path | Programme and access | Equipment health |
| Typical work pattern | 12-hour day/night shifts | Standard hours | Standard hours or campaign |
| Best for | Equipment replacement, tie-ins, modifications | Records, documentation, design input | Mill, kiln, crane, conveyor geometry |
| Primary risk managed | Restart delay from poor fit | Inaccurate records | In-service mechanical failure |
For most operators the shutdown survey is the high-stakes variant: same craft, but failure means lost production, not just a corrected drawing.
Where shutdown surveys are used
Shutdown surveys support any continuous-process operation that periodically stops for maintenance, and Australia's resources and heavy-industry sectors run these outages constantly.
Mining and mineral processing
Iron-ore, gold and base-metal processing plants across the Pilbara, Kalgoorlie Goldfields and Mount Isa stop for planned shutdowns to replace mill liners, crusher components, conveyor structure and chutes. Shutdown surveys set out and verify these replacements so the plant restarts on schedule, often alongside mill and conveyor alignment.
Alumina, cement and steel
Calciners, kilns and rotating equipment at the South32 Worsley and Alcoa Pinjarra/Wagerup alumina refineries, and at cement and steel plants, are surveyed during outages for refractory works, equipment replacement and brownfield modifications where new and existing plant must marry exactly.
Coal handling and power
Coal-handling plants in the Hunter Valley and Bowen Basin, and power-station boiler and conveyor systems, use shutdown surveys to capture as-built geometry and set out structural and mechanical changes during scheduled outages.
Ports and bulk materials handling
Ship loaders, reclaimers and conveyor systems at iron-ore and coal export ports such as Port Hedland, Gladstone and Newcastle are surveyed during maintenance windows, where access to the machine is limited to the shutdown period.
Shutdown survey equipment and deliverables
A shutdown survey relies on survey-grade instruments calibrated to ISO 17123 standards, chosen for speed of capture and reliability in a congested, time-critical plant.
| Capture method | Instruments | Accuracy | Best use |
|---|---|---|---|
| Robotic total station | Leica TS16/TS60, Trimble S9 | ±0.6 mm + 1 ppm | Setout, alignment, discrete points |
| Terrestrial laser scanning | Leica RTC360, FARO Focus, Trimble X7 | ±1–2 mm at 10 m | Whole-area as-built, clash detection |
| Digital level | Leica LS15 | ±0.3 mm/km | Foundation and baseplate levels |
| UAV / drone (external) | DJI Matrice with RTK | 20–50 mm | High structures, roofs, stockpiles |
Where drones are flown over an operating site, work is conducted under CASA Part 101 with a remote pilot licence and an operating certificate. Deliverables are referenced to the plant's local engineering grid rather than GDA2020/MGA2020 or AHD, because what matters during a shutdown is how new work fits existing plant, not its position on the national datum.
Frequently asked questions
What is a shutdown survey?
A shutdown survey is precision dimensional, alignment and as-built measurement performed while a plant is offline during a planned or unplanned outage. It captures the exact position, level and clearance of equipment so that replacement parts, modifications and tie-ins fit first time when the plant restarts, protecting the critical path of the shutdown.
How accurate is a shutdown survey?
A shutdown survey typically achieves ±0.5–2 mm for equipment setout, alignment and as-built tie-ins, using survey-grade robotic total stations and laser scanners. Accuracy depends on the stability of the local control network, the capture method, and site conditions such as vibration, dust and access. Critical alignment tasks can be tightened to ±0.1–0.5 mm where the scope requires it.
How is a shutdown survey different from a normal survey?
A shutdown survey uses the same instruments and tolerances as standard as-built work, but it is executed inside a fixed outage window, often in 12-hour day and night shifts, against a tightly managed critical path. The driving constraint is time and restart risk rather than programme convenience, which is why shutdown surveys are scoped, staffed and reported differently.
How much does a shutdown survey cost in Australia?
A shutdown survey in Australia typically costs AUD $8,000–$40,000 depending on the outage duration, shift pattern, crew size, instruments and deliverables. The cost is modest against the consequence of a restart delay: a processing-plant shutdown can lose AUD $500,000–$2 million per day, so a survey that prevents a single day's slip pays for itself many times over.
What deliverables come from a shutdown survey?
A shutdown survey produces setout data, alignment results, clearance and clash reports, as-built CAD drawings and registered point clouds, all referenced to the plant's local grid. On time-critical outages these are issued shift by shift so the next decision on the critical path can be made before the plant restarts.
What to do next
A shutdown survey is not an overhead on your outage — it is insurance against the most expensive failure in any turnaround: a component that does not fit while the clock is running and the plant is losing money by the hour. The right data, captured fast and reported faster, keeps the restart on schedule.
Industrial Spatial Solutions delivers shutdown, turnaround and outage surveys for mining, processing, alumina, cement, coal and port operations across Australia, working day and night shifts with Leica and Trimble total stations, laser scanning and rapid reporting to fit your outage window.
Call 0407 057 015 to discuss your next shutdown, or request a scope and fixed-price estimate for your turnaround survey.