Introduction: Asbestos Removal
Processes and procedures for the removal of asbestos materials including asbestos contaminated materials (ACMs) is not just a simple process of placing the materials into waste bags, skips and waste receptacles; there are more technical aspects involved:
- an asbestos survey report to locate and identify exactly where the asbestos is located including the condition of the material and amount involved,
- the requirement of specialist plant, equipment, and materials, which can only be used by persons who have received full training on how to use the materials and operate the plant and equipment.
- persons who have received and have the experience and knowledge on how where and when to install a Decontamination Unit (DCU).
- how and where to erect an asbestos removal enclosure including air lock and bagging lock
- how and where to place negative air pressure units also fitting of pre-filters.
- how to calculate and establish precise size of the negative air pressure unit (NPU) needed for required air change calculations for the required air flow through an asbestos removal enclosure (normally 10 air changes per hour)
- how and where to place h-vacuums (special vacuums fitted with hepa filters)
- how and where to place an injection machine (required for the safe removal of pipe work and sprayed asbestos insulation materials)
All the above are just the basic requirements prior to any asbestos removal works being undertaken.
Sometimes more technical abilities are required for areas of concern relating to load bearing structures and structural engineering,
Asbestos removal should only be carried out by fully experienced and licenced asbestos removal contractor/s (LARC) and below is the basic simple steps that should be carried out when asbestos removal is unavoidable.
- where asbestos is in a location where it is highly likely to be disturbed and become airborne with a high risk of fibre exposure to persons such as employees, members of the public and visitors.
Basic asbestos removal procedures
- Ensure that an up-to-date asbestos survey has been carried out to locate, identify the condition and amount; a in depth refurb/demolition asbestos survey should be carried out especially for asbestos involved in refurbishment and demolition works as this type of survey will include the fabric of the building, such as above false ceilings, within cavities and behind partition walls.
- Carry out a site visit to document, take photos and make an assessment of the works, plant equipment, materials and labour resources and experience to be involved and also gather information required for the works specific method statement and risk assessment; importantly assess if the works will affect other trades, members of the public and services of the premises.
- Compile and generate a works specific method statement and risk assessment covering the date time for start and duration of works, process and procedure from when firstly arriving onsite to completion of works, and must include the plant, equipment and materials to be utilised, location of enclosure including air locks and bag locks, NPU calculations, asbestos removal techniques and procedures to be used, amount of labour to be deployed, site sketch/plan, name of site supervisor and contract manager, air monitoring procedures, completion of works procedure.
- Notify the regulatory authority of the start and completion of works that are to be carried out.
- Normally a method statement or plan for the removal works would be set out as 1 to 23 points as an example for the removal of asbestos insulation boarding (AIB) noted below:
Example of a completed asbestos works for the removal of asbestos insulation boarding
- Decontamination unit to be set-up and made operational and tested.
- All signage (Warning, Transit and Waste Route Signs) to be positioned.
- Portable, mobile scaffolding tower will be used to high level access, step ladders and hop ups are to be used only for short duration works (no longer than 10 minutes).
- Electrics immediately adjacent the works are to be isolated.
- The whole of the (exact room location) area will become the whole of the enclosure
- 1 No.3 stage airlock and 1 No.3 stage bag lock will be erected and connected directly and immediately onto the enclosure. These air/bag locks will be constructed using metal speed frames, timber, 1000 gauge polythene, spray glue and cloth tape.
- A 5000m3 NPU will be connected to the enclosure with a roving head attachment if required to allow sufficient air flow of 10 No air changes per hour throughout the enclosure. (See plan).
- Enclosure to be constructed using building fabrics, 2 x 2 timbers, 1000-gauge polythene, spray glue and cloth tape (See Plan).
- 3 x 110 v H-Type vacs will be placed inside the enclosure for environmental cleaning. H-Type vac will be positioned at the airlock (for operative personal decontamination and for cleaning of asbestos waste sacks).
- Remaining areas of enclosure to be sealed using timber, polythene, cloth tape and if required spray adhesive. Any holes where services pass through walls will be sealed with expanding foam.
- Supervisor to inspect perimeter of enclosure for possible leakage and or breaches. Seal any areas identified as potential leakage points.
- Before works commence a smoke test will be carried out and witnessed by the Supervisor and client’s representative if available.
- On completion of a successful smoke test operatives will don correct RPE (Full Face Positive Pressure Mask with P3 Filter) and PPE (red coveralls, safety wellingtons and gloves) to commence removal works.
- The insulation boarding is nailed with no visible screws (See Pics).
- All non-asbestos materials within the immediate area will be removed and disposed of as asbestos contaminated waste, to enable unhindered access to the insulation boarding, whilst using the shadow vacuum technique, the operatives will proceed to dampen the insulation boarding using fibre suppressant applied via a fine mist from an hand-held pump spray.
- Following the dampening of the insulation boarding and allowing adequate soakage time (dependent upon size and thickness of boarding) the operatives whilst still utilising the shadow vacuum technique will proceed to carefully remove the insulation boarding (exact location), the residue within the (exact location) areas will be dampened with fibre suppressant, allowing adequate soakage time and then placed into asbestos labelled sacks; the area will then be vacuumed by operatives using H-Vacuums and all movements during these works will be shadowed by another operative using an H-Vacuum
- Once all removals are complete the area and enclosure will be cleaned with vacuums and tak-rags (grease impregnated cloths).
- Fully decontaminate the enclosure using H-vacuum cleaners and all surfaces to be wiped down with damp disposable cloths.
- Bag and double bag all contaminated materials including items that have been used within the area.
- All asbestos waste parcels/sacks to be treated with a fibre suppressant and water solution prior to removal from enclosure.
- Remove sacks/parcels containing asbestos waste from working area and transport utilising the dedicated waste routes to the sealed asbestos waste disposal skip. The supervisor is to ensure that the waste route is uninhabited prior to commencement of waste run. Waste to be removed at end of works and asbestos waste disposed of as per current asbestos waste disposal legislation with completion of section 62 asbestos waste certification.
- On completion of the works the Site Supervisor will carry out a visual inspection of the work area ensuring the area is free from dust and debris prior to handing the enclosure over to the appointed UKAS accredited analyst who will carry out the 4-stage clearance procedure.
On satisfactory completion of the 4-stage clearance procedure, a copy of the independently UKAS accredited 4 stage air clearance certification and the area will be handed back to the client for re-occupation.
Asbestos waste management involving technical aspects
Asbestos waste management and technical aspects vary from country to country as they adopt and utilize different procedures and policies regarding the management of asbestos waste including the disposal element as an example:
Environmental Protection Agency (EPA) hazardous waste regulations slightly differ than those of HSE Health and Safety Executive and Environment Agency hazardous waste regulations:
In Germany, waste containing asbestos is normally disposed of permanently in special landfill sites or sections thereof. Unfortunately, attempts at large-scale asbestos fiber destruction with concurrent cement matrix recycling have been unsuccessful.
In the Netherlands there are four basic techniques for destroying asbestos fibers, with several intermediate forms.
- Thermal techniques: these techniques are based on the fact that asbestos decomposes at high temperature and hence is no longer carcinogenic. For example, there are techniques for destroying asbestos with ovens, plasma torches or microwave radiation. By adding chemicals or clay, the process can be speeded up and operated at a lower temperature.
- Chemical techniques: with chemicals one can destroy asbestos fibers. There are techniques that work with acids and those that work with bases. Sometimes the process is accelerated by bringing it to higher temperature and/or pressure (there are also chemical processes that generate heat and therefore require cooling). Often an additional purpose is to be able to use organic waste, waste acids from industry or captured CO2.
- Mechanical techniques: the fibers can be broken down by grinding asbestos very finely. For this purpose, special high-energy mills are used, which not only effect physical, but also chemical and chemical transformations, resulting in very fine, non-toxic powder.
- Biological techniques: finally, fungi and bacteria can also break down asbestos. This happens very slowly in nature. With the creation of the right conditions, this process can be fastened considerably. For now, it has been proved that loose fibers of asbestos of the chrysotile type can be broken down in this way.
In certain cases, reuse of asbestos is of secondary importance, another part of the waste stream has the economic value [Editor’s comment: reuse/recycle of asbestos is not recommended from the standpoint of health. The author alludes to this in the below section “Re-use off and later sections]. This is the case, for example, for recycling asbestos containing metal scrap into clean, reusable metal. Finally, in soil contaminated with asbestos, the economic value of asbestos waste treatment does not primarily lie in the reusability of the soil itself, but also in the excavation and remediation costs that are avoided.
Risk aspects: the less asbestos-containing waste is transported and pre-treated (dried, shredded or crushed), the less strict measures are necessary for the protection of employees, local residents and the environment, and the smaller the risks that something can go wrong. In addition, certain technologies may require measures to work safely with aggressive substances, increased temperature and/or pressure.
Potential CO2 footprint: asbestos waste treatment techniques that use relatively more energy have a larger potential carbon footprint (although of course this can be reduced by using energy from renewable sources). For a good comparison, however, this potential footprint must be balanced by what CO2 emissions the product to be reused would have caused if it had been produced in a regular manner. Steel production from ore or ordinary metal scrap requires similar amounts of energy as recycling asbestos containing metal scrap. The same goes for the regular production of cement. The production of less active fillers requires less energy.
Closest to (the Dutch) market appears to be the technique for recycling asbestos containing steel scrap in steel melting furnaces. This is a regular steel recycling technique with melting furnaces, in which special measures have been taken for dealing with asbestos containing steel scrap in a safe way. The technology is mature and appears to be sound. There are no indications of lack of administrative and public acceptance. Several other thermal techniques are a little more distanced to the (Dutch) market but could possibly advance (possibly in a few years’ time) if the conditions are right. An important example of this is the technique for thermal denaturation, in which asbestos containing waste is driven (for 75 hours) through a tunnel kiln and is brought to a temperature of 1000 °C, as a result of which the asbestos loses its fiber structure.
The thermo-chemical treatment technique
A combustion technique in which the decomposition of the asbestos (at a temperature around 1200 °C) is speeded up by adding chemicals. However, for this technique some final technical tests must also be passed.
Biological techniques which aim at accelerating the natural degradation of asbestos fibers by bacteria or fungi are currently still technologically immature. However, soon as this technique is somewhat more under control, further discussions can be expected for in situ treatment of asbestos contaminated soil, and the barriers to entry to the market appear to be very low. Energy consumption and potential CO2 footprint of biological techniques are minimal. However, the safety of working with fungi, bacteria and any additives must be addressed, with guaranteed safeguards put in place.
The historical record of chemical asbestos waste treatment techniques is rather poor. It has been known for quite some time that asbestos fibers can be destroyed by attacking them with strong acids or bases. Attempts to apply this principle on larger scale have so far mostly failed because of problems with controlling the risks of the physico-chemical process and the need to neutralize the end-product before it can be reused.
In UK all asbestos products or materials that are deemed ready for disposal are defined as asbestos waste. Asbestos waste also includes asbestos contaminated building materials, tools that cannot be decontaminated, personal protective equipment and damp rags used for cleaning. If in doubt, always treat waste as ‘Hazardous’ or ‘Special’. See below for more details.
England and Wales
Asbestos waste is ‘Hazardous Waste’ when it contains more than 0.1 % asbestos. The Hazardous Waste Regulations 2005 apply. Complete a Hazardous Waste Consignment Note. Contact the Environment Agency for more information in England. Contact Natural Resources Wales for more information in Wales.
Asbestos waste is ‘Special Waste’ when it contains more than 0.1 % asbestos. The Special Waste Amendment (Scotland) Regulations 2004 apply. Complete a Hazardous Waste Consignment Note. Contact the Scottish Environment Protection Agency for more information.
England, Scotland, and Wales
All asbestos waste is subject to Schedule 2 of The Control of Asbestos Regulations 2012 and most waste is subject to The Carriage of Dangerous Goods and Use of Transportable Pressure Equipment Regulations 2009 (CDG 2009). CDG does not apply to firmly-bound asbestos – asbestos cement or articles with asbestos reinforcement which do not release hazardous or respirable fibers easily. However, the hazardous and special waste regulations still apply. CDG applies for all other asbestos waste.
Asbestos waste must not be mixed with other waste to achieve below 0.1%
- Waste must be packed in UN-approved packaging with a CDG hazard label and asbestos code information visible
- Double-wrap and label asbestos waste. Standard practice is to use a red inner bag with asbestos warnings, and a clear outer bag with the CDG label, if required
- Avoid breaking up large pieces of asbestos waste. Instead double wrap in suitable polythene sheeting (1000 micron-gauge) and label accordingly
- To transport waste, you need a waste carriers license.
- If you carry waste, use a sealed skip, or a vehicle with the following:
- segregated compartment for asbestos
- easily cleanable
- lockable (it is not good enough to throw sheeting over a standard skip)
- Otherwise, arrange for transport by a registered waste carrier
- Safe disposal – make sure you use a licensed disposal site
- Complete a Waste Consignment Note; keep copies of these documents for three years
- All waste should be double-bagged or double-wrapped in plastic sheeting, with the correct hazard warning signs attached
- Use a lockable skip for large sections of asbestos materials
As part of your waste duty of care, you must classify the waste your business produces:
- before it is collected, disposed of, or recovered
- to identify the controls that apply to the movement of the waste
- to complete waste documents and records
- to identify suitably authorised waste management options
- to prevent harm to people and the environment
If you are not familiar with legislation:
- Use and or seek guidance if you produce, manage or regulate waste.
- For most wastes, you will need to identify if the waste has a hazardous property before you can classify or describe it.
- Seek guidance to explain how to assess if the waste displays a hazardous property and how to classify it.
Waste classification and assessment
This explains how to classify a waste and identify its hazardous properties.
You need to classify each waste so you can describe it. The classification:
- must be worked out before the waste is moved, disposed of, or recovered
- must be included on waste documents and records
- determines the controls that apply to movement of the waste
- is needed to identify a suitably authorised waste management option
Examples of the classification of common wastes for England are provided by HSE
Steps to classify the waste:
- check if the waste needs to be classified
- identify the code or codes that may apply to the waste
- identify the assessment needed to select the correct code steps to assess the waste
- determine the chemical composition of the waste
- identify if the substances in the waste are ’hazardous substances’ or ’Persistent Organic Pollutants’
- assess the hazardous properties of the waste
- assign the classification code and describe the classification code
Check if the waste needs to be classified; if you are unsure seek advice from a competent
The need to ensure the material is waste and needs to be classified.
Nearly all household, commercial and industrial wastes do need to be classified.
- This includes waste from domestic households
- The material does not need to be classified if it is either: not waste, or a waste that is excluded from classification
Construction and demolition wastes containing asbestos
Asbestos is a naturally occurring silicate mineral and exists in several chemical types – for example chrysotile (‘white’), amosite (‘brown’) and crocidolite (‘blue’) – either in a bonded or fibrous form.
- The fibres are very fine, less than 3 microns in diameter and respirable into the lung passageways where they can lodge indefinitely and penetrate tissue
- All forms of asbestos are classified the same way in a harmonised entry in the classification and labelling inventory as:
The assessment of asbestos containing waste considers both the presence of asbestos as:
- fibres that are free and dispersed, and
- identifiable pieces of asbestos containing material
If the waste contains fibres that are free and dispersed, then the waste will be hazardous if the waste contains 0.1% or more asbestos.
If the waste contains any identifiable pieces of suspected asbestos containing material (ACM), they must be assessed as set out below. This would also apply to any dispersed fibres produced by deliberately breaking up such identifiable pieces.
Where the waste contains identifiable pieces of ACM,
- any particle of a size that can be identified as potentially being asbestos by a competent person (if examined by the naked eye), then these pieces must be assessed separately. The waste is hazardous if the concentration of asbestos in the piece of ACM is 0.1% or more
- the waste is regarded as a mixed waste and classified accordingly (see example 1 for advice on how to apply list of waste codes to mixed waste). The following waste codes should be assigned to the asbestos waste as appropriate:
- 17 06 05* Construction material containing asbestos MH
- 17 06 01* Insulation material containing asbestos MH
- 17 06 05* would normally be used in preference to 17 06 01* for the asbestos in asbestos contaminated soil and stones
The most relevant asbestos wastes are listed in the table below (entries in red [KT1] and marked with an ‘(A)’ are absolute hazardous waste and entries in blue and marked with an ‘(M)’ are mirror entries:
Fibrous asbestos and asbestos cement sheet are not produced nor used any more within the European Union. Items that once were produced containing asbestos, for example tiles and wall coverings, no longer contain asbestos.
Waste asbestos is generated when removing from the environment a toxic and carcinogenic substance and replacing it with a safer alternative. The only option for waste prevention of this material is to leave the asbestos products where they are, but this may not always be practical.
Reduction of asbestos-based wastes is mainly achieved by ensuring that they are kept separate from other wastes to prevent cross contamination. This can be achieved using well-managed removal or demolition processes: these processes are controlled by the HSE.
Re-use off site
There are no direct re-use options for these process outputs as currently there are no processes that produce a recycled product from asbestos.
The only option that could be considered recovery for fibrous asbestos is plasma vitrification, although this is a high energy activity and there is potential for land, water and air pollution and harm to human health using this treatment method. The waste glassy output from the process might be used in construction as a replacement for glass. Currently there are no facilities undertaking plasma vitrification in the UK.
Asbestos cement products are unlikely to be recovered due to the presence of the binder material used in its manufacture and make up matrix.
Waste fibrous asbestos could be solidified, by mixing with cement or resins to bind the asbestos fibres in a solid matrix. This process requires raw material use and energy input. It also has the potential for fibre release (impacting on air, water, land and human health) due to storage prior to, during and after processing. The treated asbestos waste will still need to be landfilled.
Asbestos cement is by its nature bound in cement so treatment using cement or any similar material is not necessary.
There are specific WAC (Waste Acceptance Criteria) for asbestos to be landfilled.
Other disposal except landfill
There are currently no viable recycling, recovery or treatment options in the UK so asbestos cement can be double bagged and landfilled into a separately engineered cell; note that there are specific requirements for the landfill of asbestos in the Landfill Directive. Similarly, asbestos fibres may also be double bagged and landfilled in a separately engineered cell.
As there are currently no viable recovery options readily available in the UK, landfill is the only available option.
For more details on the safe handling of asbestos wastes see the appropriate enforcing authorities HSE – EPA web sites.
Asbestos Waste Management in Developing Countries
Processes and procedures for the disposal of hazardous waste including asbestos materials, vary from country to country.
Procedures for EU and Western countries are subject to strict regulations, monitoring and involvement of governing bodies such as:
- Environment Agency (EA)
- Environmental Protection Agency (EPA)
- Health and Safety Executive (HSE)
- Government Legislation
- Government Inspections
- Landfill Waste Licence
- Waste Carriers Licence
- Transportation Tracking and Tracing
- Safe Operating Procedures (SOPs)
- Method Statements (MS)
- Risk Assessments (RAs)
- Annual Training and Exams
- Analytical Air Monitoring
- Respiratory Protection Equipment (RPE)
- Personal Protection Equipment (PPE)
- Storage of Waste Data Statistics
Asbestos and hazardous waste management processes and procedures for developing countries, are less rigid and robust to those of developed countries on a vast huge scale. Falling well short of the guidelines and requirements stated by the:
- ASEAN Secretariat
- United Nations Environment Regional Study – Waste Management in the ASEAN Countries
- World Health Organisation (WHO)
Example of Asbestos consumption in metric tonnes (estimated) 2008 - 2011:
Countries consuming asbestos in 2013
Note. excludes countries that consumed less than 1,000 tonnes.
Source: US Geological Survey.
Countries producing asbestos in 2013
Source: US Geological Survey.
As an example, the information above shows that for 2013:
- China produced 420,000 metric tonnes of asbestos materials
- China consumed 570,000 metric tonnes of asbestos materials
- China imported 130,000 metric tonnes of asbestos materials for this 2013 year
- Russian Federation produced 1,100,000 metric tonnes of asbestos materials
- Russian Federation consumed 432,000 metric tonnes of asbestos materials
- Russian Federation exported 668,000 metric tonnes of asbestos materials
Asbestos and hazardous waste management processes and procedures for developing countries, are less rigid and robust relative to developed countries on a vast huge scale. Falling well short of the guidelines and most likely related to the requirements of:
- government and company investment
- government and company interaction and communications
- knowledge and awareness
- specific training and workshops
- stricter enforceable legislation and regulations
- asbestos tracking and monitoring
- rigid controls on production, importation and exportation
- total transparency
Asbestos is a deadly material that causes a variety of cancers which often prove fatal and is a material that you must handle with great care and removal should always be carried out by knowledgeable and experienced specialists.
All information supplied is a combination of personal knowledge, experience of working within the asbestos industry, documented studies, resources and information produced by:
- International Asbestos Research on Cancer (IARC)
- World Health Organisation (WHO)
- United Nations (UN)
- Research Gate
- Health and Safety Executive (HSE)
- Environmental Protection Agency (EPA)
- Environment Agency (EA)
List of Abbreviations