Most surface preparation assumes you can close the area off. Build containment, run the blast, recover the media, clean up, hand it back. On a site that cannot stop, that assumption falls over and the job either does not happen or happens at three in the morning at considerable cost.
What makes a live site hard
Abrasive blasting throws media everywhere by design. Near production lines, food handling, pharmaceutical areas, switchrooms, data halls or anywhere with sensitive equipment, that is a serious problem. Media gets into places nobody planned for. Dust travels. The containment needed to prevent it is often a bigger build than the actual works.
Chemical stripping brings its own difficulties. Runoff has to go somewhere, fumes affect people who are still working nearby, and dwell times mean the area is out of use far longer than the labour hours suggest.
Both are why so much maintenance gets deferred on operating assets. The preparation is harder than the repair.
Why laser suits it
There is no abrasive, so there is nothing to escape and nothing to recover. There is no water and no chemical, so there is no runoff. What comes off the surface is captured at the head by extraction and filtered.
The work zone is a defined area around the head rather than a sealed enclosure around the whole work face. On a plant walkway or in an occupied basement that is the difference between a job that can proceed and one that cannot.
It is also selective. You can remove coating from a specific beam, weld or repair area without touching anything around it, which matters where the surrounding coating is sound and you have no intention of disturbing it.
The controls that still apply
Being able to work without containment does not mean working without controls, and anyone suggesting otherwise has not run one of these jobs.
This is a Class 4 laser process. That means an established controlled zone with screening, correct eyewear for the wavelength for everyone inside it, an operator trained for the equipment, and management of reflective surfaces which are common in plant environments. On an operating site it also means people who are simply walking past need to be kept out, which is a permit and supervision issue rather than a technical one.
Fume extraction is not optional. The coating leaves as particulate and fume, and whatever was in the coating is in the fume. On a lead or otherwise hazardous system that is the primary exposure control.
Hot work permits usually apply. The process produces heat and light and most operating sites will treat it accordingly. Sort that out early, because on a refinery or a food plant the permit process is often the longest lead item.
Typical work of this kind
Structural steel maintenance inside operating plants. Coating removal around welds for inspection during a short shutdown window. Cleaning down plant and equipment where dismantling is not practical. Removing coating and corrosion from services in occupied buildings. Work over water where recovering abrasive is difficult or not permitted.
The common thread is that the surrounding operation carries on, and the value is in not stopping it.
Where it does not suit
Large open areas where you can shut down and blast properly. If the plant is coming off line anyway and the area is big, blast it.
Anywhere the specification demands a new anchor profile, since the laser will not create one.
Sites where a controlled laser zone cannot be maintained because of unavoidable through traffic. That is a real constraint and it is better identified in planning than on the day.
Planning a shutdown window
If the work is tied to a short outage, the useful conversation is about sequencing rather than rates. What has to be clean before the inspection. What can be done while the plant runs. What needs the outage. A good deal of preparation work can be pulled forward out of the critical window precisely because the laser does not require the area to be shut.
That is usually where the saving is on a shutdown, not in the hourly rate.
Related reading: laser cleaning or abrasive blasting.
Talk it through
We do this work for industrial asset owners and their facility managers, infrastructure owners, principal contractors, asset managers and heritage architects, to the engineer's or heritage architect's specification. We do not take on homeowner, house, cottage, fireplace, strata, balcony, apartment or single dwelling work, or small domestic jobs.
Our laser cleaning, rust and paint removal page covers what we run and where we work. Ring 02 7912 3054 and describe the job. We will tell you straight whether the laser is right for it.
Perfect Remediation acknowledges the Aboriginal and Torres Strait Islander people as Traditional Custodians of the country on which we live and work. We pay our respects to the Traditional Custodians and Elders past, present and future, and honour their connection to the land and ongoing contribution to society.