The safest way to remove asbestos is to empty the building first. It is what we price first and what we recommend first, every time.
It is also, quite often, not available. Plant rooms serve buildings that cannot go cold. Signalling and control equipment runs whether we are there or not. Wards, kitchens, production lines and care homes do not close because a contractor has arrived. When the safest option is not achievable, the answer is not to pretend the constraint away — it is to design the job around it, and to control the access properly.
Start by saying which option is which
There is a hierarchy, and it is worth writing it down before anyone starts negotiating:
- Remove the constraint. Shut down, decant, isolate, provide temporary supply. Safest, usually most disruptive, sometimes cheaper than people assume once the phasing is priced.
- Remove the asbestos around the constraint. Segregate what has to stay live, exclude it from the working enclosure, and work around it.
- Control access into the live enclosure. Where equipment inside the enclosure genuinely has to be reached during the works, entry becomes a planned, supervised, documented procedure.
Most jobs end up as a mix of 2 and 3. What matters is that option 1 was priced and offered, and that the client chose with the difference in front of them. A contractor who never offers the safest option is not saving you money, they are moving a decision you should have made.
What “live” actually means on site
It covers more than electricity:
- Live services and plant — switchgear, control panels, boilers, calorifiers, pumps, gas, steam, water.
- Live operations — a building that trades, treats, manufactures or runs trains through the works.
- Occupied premises — staff, residents, patients, pupils, tenants who are still in the building.
- 24/7 assets — infrastructure with no natural window at all.
Each of these constrains the job differently. Live plant constrains where the enclosure can go. Live operations constrain when work can happen. Occupants constrain both, and add a duty to keep them informed.
Designing the enclosure around what has to keep running
Where equipment must stay operational, the first move is to get it out of the working area rather than to work carefully near it. In practice that means:
- Sheeting and sealing the equipment, then physically excluding it from the working enclosure so removal can proceed without any risk of disturbance to it.
- Separate enclosures per room rather than one large enclosure, so a fault or an access requirement in one area does not stop the other.
- Negative pressure throughout, with controlled Class H vacuums, wetting and continuous air monitoring.
- Transit routes and waste routes planned away from occupied areas, with cones, barriers and agreed timings.
- Out-of-hours and phased working where daytime access is impossible.
- Permits to work for the non-asbestos risks that come with live plant — electrical isolation, heat, confined spaces, manual handling.
None of this is exotic. It is the ordinary way a licensed job is planned when the building cannot stop.
Planned maintenance access into a live enclosure
Sometimes exclusion is not enough — the panel that needs checking is inside the enclosure. That is not a reason to say no, and it is not a reason to wave someone through in a paper suit. It is a written procedure agreed before the works start.
The shape of it:
- Entry preconditions. A valid asbestos medical, the right category of training for what they will do, a site-specific induction and RAMS briefing, correctly fitted PPE and face-fit-tested RPE, and an air test confirming acceptable fibre levels before entry.
- A supervisor outside, permanently. One named person controls access, holds continuous radio contact with everyone inside, watches enclosure integrity and runs the emergency response. They do not have another job while that is happening.
- An escort inside, permanently. A licensed operative stays with the visiting engineers at all times, opens any sheeted equipment in a controlled way so the checks can be made, and reseals it before anyone leaves.
- A defined scope. Works are limited to the identified equipment. No other material or surface is disturbed, and movement is kept to a minimum to reduce disturbance.
- Staged decontamination on the way out — vacuum down, wipe down, remove PPE in sequence through the airlock stages, transit PPE, then the hygiene unit: shower with RPE on, filters removed in the shower, shower continued, clean end, dry, RPE stored on charge.
- A record. Entry and exit times, what was done, anything that went wrong, and a post-shift air test so the enclosure is known to be safe for the next access.
Retford Station is a straightforward example of that arrangement. The relay room and boiler room both had to be cleaned of asbestos, and both had to stay available — they are critical to rail operations and cannot be taken out of use for the duration of the works. The live relay switchboards were fully sheeted and physically excluded from the working enclosure. Two Network Rail engineers were trained, at our request, so that if urgent maintenance was needed they could enter under the supervision of our supervisor rather than the works having to stop. From the point of contact, we could attend site within two hours.
It is worth being clear about what that arrangement is not: it is not a shortcut, and it did not reduce the controls. It added a procedure, training and supervision so that the asbestos work and the railway could both carry on. Read the Retford Station case study →
When the occupants are the constraint, not the plant
Some buildings cannot be emptied for reasons that have nothing to do with engineering.
At Nazareth House, a care home, the residents are elderly and could not be left without heating. That is not a programme preference — it decides the job. Where the constraint is people rather than plant, the levers are different: phasing so that only part of the system is ever off, temporary provision where it can be arranged, working room by room or wing by wing, working out of hours, and communicating with staff and families before anything changes rather than after.
The asbestos controls do not relax because the building is occupied. If anything they tighten, because the enclosure is now surrounded by people who did not choose to be near it: sealed transit routes, agreed timings, air monitoring, and a supervisor whose job includes the boundary between the works and everyone else. Read the Nazareth House case study →
Emergency access — decide it before you need it
The question worth asking at the pre-start meeting is: what happens if something fails at two in the morning?
If the answer is worked out on the night, it will be worked out badly. Before works start, agree and write down:
- who the client calls, and on what number, out of hours;
- how quickly a supervisor can be on site;
- who is authorised to enter the enclosure, and under what conditions;
- what happens if the failure is inside the enclosure and cannot wait for an air test;
- what the stop conditions are — containment breach, PPE failure, a medical emergency inside — and who does what in each case.
Emergency procedures are the part of a plan of work that gets skim-read, right up until the night they are the only part that matters.
What to agree before the job starts
If you are a facilities manager, estates lead or principal contractor putting this work out, these are the questions that decide whether the job runs:
- Has the safest option — full decant or shutdown — been priced and offered, so you can see what the constraint costs?
- Which equipment or systems must stay live, and which merely would prefer to?
- Will they be excluded from the enclosure or accessed within it? If accessed, whose people, trained to what, escorted by whom?
- What are the working hours, and who tells the occupants?
- Who does the air monitoring and four-stage clearance? HSE recommends the clearance analyst is independently sourced and employed by the building owner or occupier.
- What is the out-of-hours procedure, agreed in writing?
- Is the work licensable, and has it been notified to HSE 14 days before it starts?
- What does the handover pack contain, and who updates the building’s asbestos register afterwards?
Common questions
Can asbestos be removed without closing the building?
Often, yes. Work is carried out inside sealed negative-pressure enclosures with controlled transit routes, and the rest of the building carries on. Whether it is appropriate depends on the material, the location and who is in the building — which is what the survey and the plan of work are for.
Can our own engineers go into the enclosure?
Only if they are properly prepared for it: a valid asbestos medical, the right category of training, a site-specific induction and RAMS briefing, fit-tested RPE, an air test before entry, and a licensed escort with them throughout. It is arranged in advance, not on the day.
What happens to live electrical equipment inside the work area?
Wherever possible it is sheeted, sealed and physically excluded from the working enclosure so it stays operational and undisturbed. Where it has to be reached, it is opened in a controlled way by a licensed operative and resealed before exit.
Can you work nights or weekends?
Yes, and on occupied and operational sites it is often the only sensible option. It needs to be agreed early because it affects the programme, the welfare arrangements and the notification.
How quickly can you get to site if something goes wrong?
That depends on where the site is, and it should be written into the plan of work rather than promised in general terms. On our live rail work at Retford, the agreed arrangement was attendance within two hours of contact, with named supervisors on standby out of hours.
