What is an asbestos diagnosis?
An asbestos diagnosis is a methodical, documented inspection of a building aimed at detecting the presence of asbestos-containing materials (ACM), assessing their condition, and defining the appropriate measures — monitoring, encapsulation or removal. The mission is conducted by a trained, recognised specialist following standardised inspection protocols, and results in a written report that is legally and operationally actionable.
In Switzerland, asbestos was banned on 1 March 1990. All buildings constructed or significantly renovated before that date may contain asbestos-containing materials. The diagnosis answers three fundamental questions: does this building contain asbestos? Where is it and in what condition? What needs to be done before carrying out work or transferring the property?
Good to know: In Switzerland, no general obligation requires a diagnosis outside of any planned construction work. However, as soon as an intervention is planned on a building constructed before 1991, the diagnosis becomes a binding legal requirement based on the OTConst (RS 832.311.141).
Key figures: asbestos in Switzerland, a widespread reality
Available data illustrates the scale of the challenge posed by asbestos management in the Swiss building stock:
| Indicator | Estimate | Source |
|---|---|---|
| Quantity of asbestos still present in Swiss buildings | Several hundred thousand tonnes | FOEN |
| Number of different asbestos applications in construction | More than 3,000 | FACH / Suva |
| Share of Swiss residential buildings constructed before 1991 | Approximately 60% of total stock | FSO |
| Occupational diseases related to asbestos declared annually in Switzerland | Approximately 100 to 120 cases | Suva |
| Average latency period between exposure and onset of disease | 20 to 50 years | WHO |
These figures explain why Swiss regulation is so stringent — and why asbestos diagnosis remains a current issue despite a ban that is over 35 years old.
When is an asbestos diagnosis necessary?
Summary table: obligation or recommendation?
| Situation | Mandatory diagnosis? | Main legal basis | Comment |
|---|---|---|---|
| Work on buildings built before 1991 | Yes — mandatory | OTConst art. 3 and 46 | Regardless of the scale of work |
| Total or partial demolition | Yes — mandatory | OTConst + OMoD + LPE | Exhaustive inventory required |
| Disaster with property damage | Yes — before repairs | OTConst, CFST 6503 | Even in emergencies, adapted procedures apply |
| Old work premises (fitting out) | Yes — employer obligation | LTr + OTConst | Responsibility of employer/tenant |
| Before property purchase | No — strongly recommended | CO art. 197-199 | Hidden defects, possible recourse |
| Before property sale | No — strongly recommended | CO art. 197-199 | Seller’s duty to inform |
| Preventive inventory (no works) | No — good practice | — | Asset management, forward planning |
Before construction work or renovation — legal obligation
This is the most frequent and most regulated situation. The OTConst requires the employer — and by extension the client — to ensure, before any construction site commences, that workers will not be exposed to asbestos fibres. This obligation applies regardless of the scale of the work: a simple hole drilled in an old partition wall, the installation of an electrical outlet in a pre-1990 plastered wall, the replacement of floor tiles in a 1970s bathroom, or the complete rehabilitation of a building.
The scope of the pre-works diagnosis is targeted at the zones and materials likely to be disturbed. For details on all types of work concerned, see the asbestos diagnosis before work page.
Before total or partial demolition — legal obligation
Demolition requires an exhaustive inventory of the entire building. The objective is to identify all asbestos-containing materials in order to organise their disposal through appropriate channels. Asbestos-containing waste is classified as special waste and subject to mandatory traceability through tracking documents. The asbestos diagnosis before demolition page details the specificities of this mission.
Before buying or selling a property — strongly recommended
The Swiss Code of Obligations (CO, art. 197-199) requires the seller to disclose hidden defects. A seller who is aware of the presence of asbestos and does not declare it is exposed to subsequent legal action. For a buyer, the diagnosis allows an informed decision and anticipation of decontamination costs. For a seller, it allows honest disclosure and protection against future claims.
Who is concerned by the asbestos diagnosis?
Private property owners
Any villa, co-owned apartment, or holiday home built before 1991 is potentially concerned. As soon as you plan renovation work — refurbishing the bathroom, replacing windows, renovating the kitchen, insulating the attic — you are subject to the diagnostic obligation. Ignorance of the law is not an acceptable argument in the event of an inspection or accident.
Property managers and real estate agents
The common areas of an old building — corridors, technical rooms, roof, facade, cellars — may contain asbestos-containing materials. The management has a duty of diligence towards occupants and external contractors. Any company mandate on these spaces must be preceded by a diagnosis.
Clients and property developers
The legal responsibility of the client with respect to worker safety is engaged as soon as companies are commissioned on a construction site. The asbestos diagnosis is the tool that fulfils this obligation — and protects against criminal and civil liability.
Architects and engineers
In the context of rehabilitation or transformation projects, designers have an obligation to advise their clients. They must integrate the asbestos diagnosis from the study phase to anticipate constraints and costs related to asbestos removal. Failure to fulfil this duty of information may engage their professional liability.
Construction companies and tradespeople
A tradesperson working on an old building has their own verification obligation as an employer. They cannot rely solely on the owner’s word. Without an available diagnostic report, no serious professional contractor should start work on a site.
Municipalities and public authorities
Old public buildings — town halls, schools, sports centres, administrative buildings — are subject to the same obligations. Local authorities also have a transparency obligation towards users of their buildings and local government employees who work in them.
Companies renting old premises
A company renting offices or premises in a pre-1991 building and planning fit-out work engages its employer responsibilities. Being a tenant does not release the obligation to verify.
Asbestos-containing materials in buildings: more than 3,000 documented applications
Asbestos was incorporated into an extraordinary number of construction products. The following is an inventory organised by category of the most common applications in Western Switzerland’s building stock:
Roofs and external envelopes
- Corrugated and flat fibre cement sheets (ETERNIT brand and equivalents) for roofs of single-family homes, outbuildings, agricultural and industrial buildings
- Fibre cement facade cladding panels
- Artificial slates in fibre cement
- Ventilation and flue ducts in fibre cement
- Gutters, downpipes and roof accessories in fibre cement
- Flat roof composites (asbestos asphalt)
- Valleys, ridge tiles and roofing accessories in fibre cement
Thermal and acoustic insulation
- Sprayed coatings and renders on metal frameworks, beams and ceilings — the most dangerous materials due to their high friability
- Pipe lagging on heating, steam and hot water pipes (asbestos fabric wrap, asbestos pipe shells, asbestos tape)
- Composite insulating panels incorporating asbestos
- Insulation mats and sheets for old boilers and water heaters
- Insulating felts and mats between structural elements
Floor coverings
- Vinyl-asbestos floor tiles (30×30 cm format, widely used in buildings from the 1960s–1980s)
- Adhesives and mastics under vinyl or linoleum floor tiles
- Asbestos-containing bituminous underlays
- Anti-slip floor coverings in certain industrial staircases
Wall and ceiling coverings
- Asbestos-containing plasters and renders applied to interior surfaces
- Asbestos-based false ceiling plates and panels
- Acoustic ceiling tiles and slabs
- Lightweight partition boards in asbestos fibre cement
- Old smoothing compounds and joint fillers
Bathrooms and kitchens
- Tile adhesives for bathrooms and kitchens installed before 1990
- Bathtub and shower tray backing plates
- Toilet seat and vanity basin gaskets
Technical installations
- Pipe and fitting joints (water, gas, steam)
- Oven, cooker and boiler door gaskets
- Sealing joints around windows and doors (mastic beads)
- Electrical panels and junction boxes with asbestos backing plates
- Old electrical cable braids and conduits
- Fibre cement ventilation ducts
Specific applications
- Fire protection panels around fireplaces, hearths and flues
- Fire door trim
- Industrial roof sealing composites
- Floor coverings in certain industrial staircases
Important: This list, though comprehensive in its main categories, is not exhaustive. Asbestos was used in more than 3,000 documented applications. This is why the presumption of asbestos presence in any building built before 1991 is the golden rule, and why the diagnosis must be conducted by a trained specialist — and not on the basis of a simple, unqualified visual inspection.
Friable vs non-friable materials: a fundamental distinction
Not all asbestos-containing materials present the same level of immediate risk. This distinction is central to the diagnostic assessment.
| Criterion | Friable materials | Non-friable materials |
|---|---|---|
| Definition | Easily crumble by hand or at the slightest contact | Mechanically resistant, do not pulverise under normal conditions |
| Typical examples | Sprayed coatings, degraded pipe lagging, heavily deteriorated renders | Fibre cement boards, intact vinyl tiles, stable mastics |
| Fibre release without works | Yes — risk for occupants even without intervention | No under normal conditions of use |
| Fibre release during works | Very high — extreme risk | High as soon as drilled, sawn, ground or cut |
| Overall risk level | High to very high | Moderate to high depending on type of intervention |
| Priority measures | Often immediate removal or emergency encapsulation | Mandatory removal before any intervention |
| Regulatory treatment | High-risk category (CFST 6503, level 3) | Standard or high-risk category depending on type |
Good to know: A non-friable asbestos-containing material in good condition does not represent a danger to occupants as long as it is not disturbed. The decision to leave it in place, encapsulate it or remove it depends on its condition, accessibility and future plans. This is precisely the expertise that the diagnostician brings beyond simple detection.
The complete asbestos diagnosis process in 4 steps
Step 1 — Preparation and scoping of the mission
The mission begins with an exchange between you and the diagnostician. You describe your property (type, address, estimated year of construction, area), your project (nature of work, intended scope) and provide available documents: building plans, history of works, building permits, invoices for past interventions. This information allows the diagnostician to prepare the inspection, identify priority zones and anticipate materials likely to be present according to the type and era of construction.
Step 2 — On-site inspection visit
The diagnostician conducts a systematic visual and tactile inspection of all accessible zones relevant to the mission. They go through the building room by room, floor by floor, and technical space by technical space. For each suspect material, they note its precise location, assumed nature, state of conservation, area concerned and accessibility. Photographs document the condition of each identified material.
This inspection is conducted according to the protocols defined by SIA 2023 standards and the FACH Commission guidelines. The diagnostician does not limit inspection to visible areas: they also inspect attics, crawl spaces, technical ducts and utility rooms.
Step 3 — Sampling and analysis in SAS-accredited laboratory
On materials identified as suspect during the visual inspection, the diagnostician takes material samples. Each sample is taken according to a strict protocol to prevent fibre dispersal, then packaged and labelled before being sent to a laboratory accredited by the Swiss Accreditation Service (SAS).
The laboratory analyses samples by polarised light optical microscopy (PLOM), the reference method for identifying the nature of fibres (chrysotile, amosite, crocidolite, tremolite, actinolite, anthophyllite) and estimating their content in the material. For certain specific materials or situations, transmission electron microscopy (TEM) may be required, particularly for air analyses.
Analysis turnaround times generally range from 5 to 10 working days under standard conditions.
Step 4 — Report drafting and delivery
The diagnostician compiles all information and writes the asbestos diagnostic report. This structured document contains the identification of the property and mission, methodology employed, detailed inventory of all inspected materials, analysis results for each sample, risk assessment for each positive material, and action recommendations — priority removal, planned removal, encapsulation or periodic monitoring.
The report includes field photographs and laboratory analysis results as annexes. It constitutes a legally binding document for a building permit, a property transaction or a labour inspection audit.
For more on the structure and use of a report, see the asbestos diagnostic report page.
Comment se déroule un diagnostic amiante ?
Standards and benchmarks governing the diagnosis
A quality asbestos diagnosis is conducted in compliance with several standards and guidelines:
| Reference | Nature | Main content |
|---|---|---|
| SIA 2023 | Swiss standard (SIA) | Principles for remediating materials containing pollutants, including asbestos |
| OTConst RS 832.311.141 | Federal ordinance | Worker protection obligations on construction sites, prior verification |
| CFST Directive 6503 | Federal directive | Rules for working in the presence of asbestos, protection levels, required qualifications |
| FACH Guidelines | Technical recommendations | Inspection, sampling and analysis methods |
| PLOM | Analytical method | Polarised light optical microscopy — fibre identification and quantification |
| TEM | Analytical method | Transmission electron microscopy — air analyses and complex cases |
| SAS | Accreditation | Guarantees reliability and traceability of analysis laboratories |
| ORRChim RS 814.81 | Federal ordinance | Prohibition on placing asbestos-containing materials on the market since 1 March 1990 |
A construction project or a question?
Our FACH-certified diagnosticians cover Geneva and Vaud. Free quote within 24h.
The Swiss regulatory framework: complete legal architecture
The ORRChim — the basis of the ban
The Ordinance on the Reduction of Risks from Chemical Products (ORRChim, RS 814.81) has prohibited, since 1 March 1990, the placing on the market of any material containing asbestos. This prohibition does not retroactively affect materials already in place, but triggers all management obligations as soon as an intervention is planned.
The LPE and OMoD — waste management
The Federal Act on Environmental Protection (LPE, RS 814.01) and the Ordinance on the Movement of Waste (OMoD) classify removed asbestos-containing materials as special waste. They impose source separation, disposal through licensed channels, and documented traceability via mandatory tracking documents.
The OTConst — the pillar of worker protection
The Ordinance on Construction Work (OTConst, RS 832.311.141) is the central text imposing the pre-works diagnosis. Article 3 creates the obligation for every employer and client to verify the presence of hazardous substances before any construction site commences. CFST Directive 6503 is its operational technical extension.
Warning: Non-compliance with asbestos obligations is a criminal offence under Swiss law. Clients, construction companies and architects may be personally prosecuted. In the event of proven worker exposure, criminal proceedings are systematic and the amounts at stake in civil actions can be very significant, given the serious diseases that asbestos can cause decades later.
For the complete legal framework and applicable sanctions, see the mandatory asbestos diagnosis page.
Service areas — Geneva and Vaud
Our FACH-certified diagnosticians operate in the two most populous French-speaking cantons:
Canton of Geneva
Geneva city, Carouge, Lancy, Meyrin, Vernier, Onex, Thônex, Chêne-Bougeries, Grand-Saconnex, Plan-les-Ouates, Bernex, Satigny, Russin, Aire-la-Ville, Collonge-Bellerive, Cologny, Pregny-Chambésy, Versoix — and the entire cantonal territory.
Find all canton-specific information on the asbestos diagnosis Geneva page.
Canton of Vaud
Lausanne, Nyon, Morges, Renens, Prilly, Yverdon-les-Bains, Vevey, Montreux, Pully, Écublens, Gland, Rolle, Aigle, Payerne, Moudon, Orbe — and the entire cantonal territory.
Find all canton-specific information on the asbestos diagnosis Vaud page.
What to do after a positive diagnosis?
When the diagnostic report confirms the presence of asbestos, the situation is not a catastrophe: it is information that enables safe and compliant action. The steps to take depend directly on the type of material, its condition and the context.
Scenario 1 — Asbestos-containing materials in good condition, not affected by the works
If the diagnosis identifies stable asbestos-containing materials in zones not affected by the planned works, the report may recommend periodic monitoring and updating of the property’s documentation. No immediate removal is required.
Scenario 2 — Asbestos-containing materials in the works zone
If asbestos-containing materials are located in zones directly affected by the works, they must be removed by an authorised decontamination company before ordinary works commence. Removal is carried out according to CFST 6503 rules (containment, personal protective equipment, decontamination) and waste is disposed of through licensed channels with tracking documents.
Scenario 3 — Severely degraded friable materials
If friable materials in poor condition are discovered — sprayed coatings, deteriorated pipe lagging — an intervention may be necessary even without planned works, to protect occupants from chronic exposure to airborne fibres.
Good to know: Asbestos removal is not always the chosen solution. Encapsulation — covering the asbestos-containing material with an appropriate coating — can be a viable solution in certain cases, particularly for non-friable materials in good condition that are difficult to access. The diagnostician and the remediation expert (FACH level 2) jointly define the best strategy.
Other building pollutants not to be overlooked
A building constructed before 1991 may contain other hazardous substances subject to specific regulations. A multi-pollutant approach is often more effective and economical than a series of individual diagnoses.
- Lead: present in old paints (white lead), pipework and certain solders, with serious health risks particularly for children. Learn more about lead diagnosis.
- PCBs: polychlorinated biphenyls in sealant joints, mastics and paints in collective buildings from 1955–1975. Learn more about PCB diagnosis.
- PAHs: polycyclic aromatic hydrocarbons in tars, bituminous parquet adhesives and certain coatings. Learn more about PAH diagnosis.
- HBCD: hexabromocyclododecane in expanded polystyrene foams used for thermal insulation. Learn more about HBCD diagnosis.
Why choose a FACH-certified diagnostician?
In Switzerland, professional recognition of asbestos specialists is managed by the FACH Commission (Fachkommission Asbest und andere Schadstoffe im Hochbau). This body defines the required competence levels, grants recognitions and maintains registers of qualified professionals.
| FACH Level | Competence | Application |
|---|---|---|
| Level 1 | Diagnosis and assessment of contaminated buildings | Carrying out asbestos diagnoses |
| Level 2 | Planning of remediation measures | Drawing up decontamination plans |
| Level 3 | Direction of remediation works | Managing decontamination sites |
A report produced by a practitioner without FACH recognition may be refused by cantonal authorities when applying for a building permit. In the event of a dispute or inspection, the probative value of a FACH report is unquestionable. For more on selection criteria, see the asbestos diagnostician Western Switzerland page.
Complete overview — all our thematic pages
To explore each aspect of asbestos diagnosis in depth:
- Asbestos diagnosis before work — legal obligations and types of work concerned
- Asbestos diagnosis before demolition — exhaustive inventory and procedures
- Mandatory asbestos diagnosis — complete legal framework and sanctions
- Asbestos diagnosis price — cost factors and pricing transparency
- Asbestos diagnostic report — structure and use of the report
- Asbestos diagnostician Western Switzerland — how to choose your expert
- FAQ asbestos — all practical questions
Request your no-obligation quote
Do you have a construction project, a demolition to plan, an ongoing property transaction or simply a concern about asbestos in an old building? Call us on +41 58 590 91 92 or fill in the form on the asbestos diagnosis quote page. We respond within 24 business hours with a proposal tailored to your property and project.