The level of risk from occupational exposure to asbestos: guidance for HSE and LA staff when responding to enquiries

To:  Health and Safety Enforcing Authorities

For the attention of: Local Authority Health and Safety Enforcement Managers, Health and Safety Regulators and others

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This Local Authority Circular (LAC) provides technical guidance to health and safety regulators and others on the risks from asbestos. The LAC provides guidance to help to respond to enquiries from employers, employees, trade unions and members of the public (MOPs) following exposure or suspected exposure to asbestos. Three attached Information Documents (IDs) may be given to employers (ID (1)) employees and member of the public (ID (2)) and GPs and occupational health professionals (ID (3)).

Introduction

People who may have been exposed to asbestos are understandably anxious and concerned about the possible effects on their health. Moreover, where incidents involve members of the public or vulnerable sections of the population, widespread publicity and requests for advice may result. This LAC gives health and safety regulators advice on how to deal with such requests consistently.

There is at present no effective post-exposure prophylaxis for the effects of inhaled asbestos fibres, although in smokers the risk of asbestos-induced lung cancer (but not mesothelioma) can be reduced by stopping smoking. There are also no generally available techniques for determining individual lung burdens of asbestos fibres, other than post mortem.

HSE does not advocate routine X-rays for people exposed to asbestos in the majority of such circumstances. (Asbestos-related damage to the lungs takes years to develop and become visible on chest X-rays, and X-ray examinations cannot indicate whether or not asbestos fibres have been inhaled.)

Action required

Asbestos incidents arouse concern and anxiety, and often unrealistic expectations of medical tests or even treatment. This should be addressed by offering prompt and reasoned advice, without contributing to unnecessary alarm. The guidance in this circular and the IDs should be sufficient in many cases and is intended to assist those responsible for managing such situations.

In circumstances where cases of exposure to asbestos may have occurred, the following issues should be considered:

1. Ascertain as far as possible the type of asbestos, the likely exposure levels involved and the duration of exposure. Consult with an HSE occupational hygiene inspector to provide a context of overall life-time risk that includes the alleged exposure.
2. Whether enforcement action is appropriate where there is sufficient evidence to show a significant exposure. Enforcement guidelines can be found in OC 265/50
3. Whether the incident is reportable as a Dangerous Occurrence to HSE’s Incident Contact Centre (Tel: 0845- 3009923).  Examples of types of work that could be classified as a Dangerous Occurrence are listed in Section 3.1 of ID(1)..
4. That the duty-holder has considered how to prevent a re-occurrence of the circumstances that led to the incident.
5. Employers asking about retention of records should be advised that, under the Control of Asbestos Regulations 2006, they are not required to retain health records for those working with asbestos, unless they carry out licensed work. Health records for employees of licence-holders should be retained for 40 years.
6. Consider offering those involved: employers, employees or members of the public, the opportunity to discuss the situation with a medical or occupational health inspector, particularly where they are otherwise unlikely to have access to an occupational health service.
7. Advise employees that if they wish to consult their GPs they should ask for a note to be made in their personal record of the possible exposure including date(s), duration, type of fibre, and likely exposure levels (if known). Advise them that their GP may refer them to a specialist in respiratory medicine in some circumstances, but that this is not considered necessary by HSE in most cases.
8. Providing employers with a list of occupational health services from EMAS if they choose to refer employees for assessment and counselling.
9. Liaising with the Director of Public Health/Director of Environmental Health, via a medical inspector, in circumstances where concerns are raised about off-site effects and risks to members of the public.
10. The provision of the relevant Information Document (attached) for employers (ID (1)) employees and member of the public (ID (2)) below) and GPs etc (ID (1)).

Reporting activity and impact of the Fit3 Programme (LA Inspectors)

When planning and implementing work within the Fit3 programme it is essential to feedback details of activities and outcomes to HSE. This is to allow monitoring of progress towards the Disease Reduction Programme (Cancer Project) objectives and where necessary to refocus work activities and to consider the adequacy of current support. Feedback also provides invaluable information for the Health and Safety Commission/HSE & LA Enforcement Liaison Committee/Local Authority Unit when responding to Ministers and the Local Better Regulation Office (LBRO) on the achievements of the LA/HSE partnership. Please use one or more of the following ways to record your activities and achievements both quantitatively and qualitatively:

• provide feedback 'in year' to Partnership Teams
• complete the topic inspection report forms on the HELA Training Co-ordination website
• upload information onto the Extranet e.g. as an example of good practice
• contribute to research based evaluation work (if requested), sponsored by certain key Fit3 projects/programmes (e.g. Better Backs Campaign)
• apply for HELA annual awards
• complete the LAE1 form for the appropriate year
• Return a completed form ASB6 to HSE’s Asbestos Licensing Unit after inspecting licensed asbestos work.

Background: factors that influence of the level of risk

Inhalation of asbestos fibres can lead to very serious diseases such as mesothelioma and lung cancer in later life. Much of the current burden of asbestos-related disease (about 4000 deaths per year) is a result of past heavy industrial exposures among those who manufactured and installed asbestos products. However, HSE is now concerned about lower exposures that may still lead to disease, particularly since specific exposure incidents could form part of a pattern of repeated exposure among some workers (such as electricians, plumbers and carpenters), leading to a substantial cumulative exposure.

We are all exposed to a low level of asbestos fibres because asbestos was such a widely used material within buildings, machinery, vehicle brakes and homes until 1999, when most forms of asbestos were banned. However, working directly with asbestos containing materials (ACMs) can give personal exposures to airborne asbestos that are much higher than environmental levels.  Repeated exposures of this type will give rise to a substantial cumulative exposure, thereby increasing the risk of developing an asbestos related disease in the future. The aim of the Control of Asbestos Regulations 2006 is to prevent or reduce additional work-related exposure to asbestos fibres. 

• More detailed guidance on the factors that impact on the level of risk from the differing types of exposure patterns are detailed in section 3 of ID(1).
• Please contact the Asbestos Licensing Unit of HSE if you wish to discuss the content of this LAC on Tel: 0131 247 2136

Further guidance/sources of information

Information about the current asbestos campaign and practical guidance on controlling exposure (‘Asbestos Essentials Task sheets’) can be found on HSE’s website, along with the following guidance leaflets etc:

1. A short guide to Managing asbestos in workplace buildings (INDG223); Available at http://www.hse.gov.uk/pubns/indg223.pdf - For those working in building maintenance, repair and refurbishment (available in priced packs of 10).
2. Free Leaflet ‘Manage Buildings? You must manage asbestos’ - A jointly badged leaflet produced by HSE in conjunction with the Trades Union Congress, The Royal Institute of Chartered Surveyors, The Federation of Small Businesses, The Asbestos Testing and Consulting Division of ARCA and The British Institute of Facilities Managers. Available at http://www.hse.gov.uk/pubns/manageasbestos.pdf
3. INDG 419: ‘Asbestos Kills: Protect Yourself! You are more at risk than you think’ - a new leaflet for maintenance workers.  Available at http://www.hse.gov.uk/pubns/indg419.pdf
4. INDG 418: ‘Asbestos Kills: A Quick Guide to Protecting Yourself’ – A new pocket card for maintenance workers.  Available at http://www.hse.gov.uk/pubns/indg418.pdf
5. Campaign packs produced as part of the HSE’s Asbestos campaign - ‘Asbestos – The Hidden Killer’. The pack is A5, plastic wrapped and contains the new pocket card (INDG 418) and the new leaflet (INDG 419) for maintenance workers on the risks associated with asbestos. It also has a promotional flyer for the revised ‘Asbestos Essentials Task Manual’ (INDG 210) and a covering letter. To order a campaign pack, e-mail HSE Books direct using hsebooks@prolog.uk.com quoting stock code MISC806 or alternatively you can order via HSE’s Infoline tel:0845 345 0055 and/or via the asbestos webpages at http://www.hse.gov.uk/asbestos/campaign/orderpack.htm
6. HSG 210 ‘Asbestos essentials Task Manual’ Task Guidance Sheets for the Building maintenance and allied trades (priced publication).
7. HSG 213 ‘Introduction to Asbestos Essentials: Comprehensive guidance on working with asbestos for the building maintenance and allied trades (priced publication).

All are available from:

HSE Books,
PO Box 1999,
Sudbury,
Suffolk,
CO10 6FS
Tel: 01787 881165 or Fax: 01787 313995

Or download/order from www.hse.gov.uk/asbestos

Information Document 1 - Exposure to asbestos from work activities: advice for employers

Following this guidance is not compulsory and you are free to take other action. But if you do follow the guidance you will normally be doing enough to comply with the law. Health and safety regulators seek to secure compliance with the law and may refer to this guidance as illustrating good practice.

Introduction

Breathing in asbestos fibres released from disturbed or damaged asbestos containing materials (ACMs) can present a real risk of developing serious diseases, including cancer (mesothelioma and lung cancer) and asbestosis. Since these diseases can take decades to develop the majority of the current cases (including 4000 plus deaths per year) are associated with the very high exposures from past industrial processes and installation of asbestos products.  The primary concern is now about potentially frequent and regular exposure patterns arising from direct work with ACMs, e.g. during maintenance activities.  Such exposures could, over time, lead to a substantial accumulation of fibres in the lungs of some workers (such as electricians, plumbers and carpenters). Your aim should be to ensure that current work with asbestos is either prevented or controlled to prevent asbestos related deaths in the future.

Everyone is continuously exposed to asbestos fibres to some extent because asbestos was such a widely used material within buildings, machinery, vehicle brakes and homes until 1999, when most forms of asbestos were banned.  However, working directly with asbestos containing materials (ACMs) can give personal exposures to airborne asbestos that are much higher than environmental levels.  Repeated exposures of this type will give rise to a substantial cumulative exposure, thereby increasing the risk of developing an asbestos related disease in the future.

Legal requirements

As an employer you must ensure that you comply with the following legal duties to prevent or control exposure to asbestos caused by work activities:

• the prevention or control (where prevention is not reasonably practicable) of exposure from work activities, including training of employees and emergency procedures to deal with unplanned  disturbance of asbestos;
• if an asbestos incident has already occurred you must consider carefully what went wrong in causing your employees to be exposed to asbestos and how you will prevent this happening again in future;
• ensure that certain higher risk asbestos work is carried out by those holding an asbestos licence issued by HSE. Contact HSE’s Infoline service on Tel: 0845 345005 for further information;
• asbestos materials in workplace buildings must be managed to prevent or control exposure to asbestos;
• the reporting of a significant uncontrolled disturbance of asbestos (asbestos incident – see examples in ‘Factors that influence level of risk’ below) as a Dangerous Occurrence to HSE’s Incident Contact Centre (ICC), Tel: 0845-3009923.

You can find out more about how HSE enforces relevant legislation and the detail of the specific regulations via the HSE’s asbestos webpages: Asbestos - Enforcement

Factors that influence level of risk

It is often difficult to accurately relate specific asbestos exposures to an increased risk of developing disease in the future. The degree of risk will depend on the total life time cumulative exposure; the type of asbestos involved and the time elapsed since the person was first exposed. The degree of cumulative exposure is dependent on the amount of fibres that are generated by the work activity and how long it lasts. The concentration of fibres in the air will be determined by the force used and extent of the disturbance as well as the ability of the ACM to release fibres. The following are examples of uncontrolled work activities likely to create a significant concentration of fibres in the air, thereby adding to the risk of developing an asbestos related disease:

• Use of power tools (to drill, cut etc) on most ACMs;
• Physical disturbance, such as knocking, breaking, smashing of a licensable ACM e.g. sprayed coating, lagging, asbestos insulating board (AIB);
• Manually cutting or drilling AIB;
• Aggressive physical disturbance of asbestos cement (AC), eg breaking or smashing.

* The timescales quoted are related to advice given in the previous version of OC 265/48 which stated  that exposure would usually have been insufficient to pose a significant long-term risk to health where Action Levels were not exceeded.  The Action Levels at that time were defined in the Control of Asbestos at Work Regulations 2002 as being 48 fibres per millilitre of air in a continuous 12 week period for all forms of asbestos and mixtures of asbestos, except chrysotile alone, and 72 fibres per millilitre of air in a continuous 12 week period where the exposure was solely to chrysotile.

Unless you have a robust asbestos management plan your employees may be disturbing ACMs without knowing it and therefore be more at risk than you think. The pattern of exposure to asbestos is a significant factor in determining the degree of risk.  The following examples illustrate the main patterns of exposure and their relative risk:

• Highest risk – carrying out licensable asbestos work (i.e. work with asbestos materials that give off fibres easily) without suitable controls;
• Higher risk – Regularly doing the type of work listed in paragraph 3.1 without suitable precautions in trades such as carpentry, plumbing, electrical, roofing and general maintenance.  The risk of developing disease is increased because a repeated pattern of exposure over time is likely to cause fibres to build up in the lungs;
• Lower risk – Working in buildings near ACMs in poor condition that are regularly disturbed releasing significant levels of fibres. The exposure could also be regular, but is likely to be at a lower level than those in paragraphs a) and b);
• Lowest risk – Being in a building when a one-off asbestos incident occurs.  The risk will be lowest because the persons involved are not regularly exposed to asbestos.

 

Medical examinations and health records

You may need to seek advice from occupational hygienists or occupational health specialists about the likely exposure levels and associated risks. You should contact HSE’s Infoline service who may be able to give general advice and provide information on the availability of local specialist services.

You are not required to retain health records for those working with asbestos, unless they carry out licensed work.  Health records for employees of licence-holders should be retained for 40 years.  You are, however, required to inform all those affected about the nature of the incident and what you have done, or are going to do, to prevent a reoccurrence.

Exposed individuals should be informed that if they wish to consult their GP they should ask for a note to be made in their personal medical record of the possible exposure including date(s), duration, type of fibre and likely exposure levels (if known). (Their GP may refer them to a specialist in respiratory medicine but this is not normally considered necessary). Each case should be considered on its merits, but HSE does not normally advocate routine X-rays for persons exposed to asbestos in these circumstances.

Alternatively, or in addition, you may choose to refer employees for counselling. You may wish to select an occupational health service for this purpose. The local office of HSE's Employment Medical Advisory Service may be able to provide information on services in the area.  Contact Infoline for further details.

Further information and guidance

Information about the current asbestos campaign and practical guidance on controlling exposure (‘Asbestos Essentials Task sheets’) can be found on HSE’s website (http://www.hse.gov.uk/asbestos/essentials/index.htm), along with the following guidance leaflets etc:

1. A short guide to Managing asbestos in workplace buildings (INDG223); Available at http://www.hse.gov.uk/pubns/indg223.pdf - For those working in building maintenance, repair and refurbishment (available in priced packs of 10).
2. Free Leaflet ‘Manage Buildings? You must manage asbestos’ - A jointly badged leaflet produced by HSE in conjunction with the Trades Union Congress, The Royal Institute of Chartered Surveyors, The Federation of Small Businesses, The Asbestos Testing and Consulting Division of ARCA and The British Institute of Facilities Managers. Available at http://www.hse.gov.uk/pubns/manageasbestos.pdf
3. INDG 419: ‘Asbestos Kills: Protect Yourself! You are more at risk than you think’ - a new leaflet for maintenance workers.  Available at http://www.hse.gov.uk/pubns/indg419.pdf
4. INDG 418: ‘Asbestos Kills: A Quick Guide to Protecting Yourself’ – A new pocket card for maintenance workers. Available at http://www.hse.gov.uk/pubns/indg418.pdf
5. Campaign packs produced as part of the HSE’s Asbestos campaign - ‘Asbestos - The Hidden Killer’. The pack is A5, plastic wrapped and contains the new pocket card (INDG 418) and the new leaflet (INDG 419) for maintenance workers on the risks associated with asbestos.  It also has a promotional flyer for the revised ‘Asbestos Essentials Task Manual’ (INDG 210) and a covering letter. To order a campaign pack, e-mail HSE Books direct using hsebooks@prolog.uk.com quoting stock code MISC806 or alternatively you can order via HSE’s Infoline tel:0845 345 0055 and/or via the asbestos webpages at http://www.hse.gov.uk/asbestos/campaign/orderpack.htm
6. HSG 210 ‘Asbestos essentials Task Manual’ Task Guidance Sheets for the Building maintenance and allied trades (priced publication).
7. HSG 213 ‘Introduction to Asbestos Essentials: Comprehensive guidance on working with asbestos for the building maintenance and allied trades (priced publication).

All are available from:

HSE Books,
PO Box 1999,
Sudbury,
Suffolk,
CO10 6FS.

Tel: 01787 881165 or Fax: 01787 313995

Or download/order from www.hse.gov.uk/asbestos

Information Document 2 - Exposure to asbestos from work activities: advice for employees and members of the public

Introduction

Breathing in asbestos fibres released from disturbed or damaged asbestos containing materials (ACMs) can present a real risk of developing serious diseases, including cancer (mesothelioma and lung cancer) and asbestosis. Since these diseases can take decades to develop the majority of the current cases (including 4000 plus deaths per year) are associated with the very high exposures from past industrial processes and installation of asbestos products. HSE is now primarily concerned about potentially frequent and regular exposure patterns arising from direct work with ACMs, e.g. during maintenance activities. Such exposures could, over time, lead to a substantial accumulation of fibres in the lungs of some workers (such as electricians, plumbers and carpenters). The aim of all enforcing authorities is to ensure that current work with asbestos is either prevented or controlled to prevent asbestos related deaths in the future.

Everyone is continuously exposed to a low level of asbestos fibres to some extent because asbestos was such a widely used material within buildings, machinery, vehicle brakes and homes until 1999, when most forms of asbestos were banned.  However, working directly with asbestos containing materials (ACMs) can give personal exposures to airborne asbestos that are much higher than environmental levels.  Repeated exposures of this type will give rise to a substantial cumulative exposure, thereby increasing the risk of developing an asbestos related disease in the future.

Legal requirements

To avoid additional exposure caused by work place activities, the law requires:

• the prevention or control (where prevention is not reasonably practicable) of exposure from work activities, including training of employees and emergency procedures to deal with unplanned  disturbance of asbestos;
• that certain higher risk asbestos work is carried out by those holding an asbestos licence issued by HSE.  HSE’s Infoline service can provide further advice on Tel: 0845 345005;
• that asbestos materials in workplace buildings must be managed to prevent or control exposure to asbestos;
• the reporting of a significant uncontrolled disturbance of asbestos (an asbestos incident – see examples in ‘Factors that influence level of risk’) as a Dangerous Occurrence to HSE’s Incident Contact Centre (ICC), Tel: 0845- 3009923.

You can find out more about how HSE enforces relevant legislation via the HSE’s asbestos webpages: Asbestos - Enforcement

Factors that influence level of risk

It is often difficult to accurately relate specific asbestos exposures to an increased risk of developing disease in the future. The risk of going on to develop disease will depend on a combination of the following factors:

• How many fibres built up in you lungs over your whole lifetime;
• The type of asbestos involved;
• How much time has passed since you were first exposed;
• How many asbestos fibres were actually released into the air that you breathed at the time of the exposure.

The following are examples of uncontrolled activities likely to create a significant concentration of fibres in the air, thereby adding to the risk of developing an asbestos related disease:

• Use of power tools (to drill, cut etc) on most ACMs;
• Physical disturbance, such as knocking, breaking, smashing of a licensable ACM e.g. sprayed coating, lagging, asbestos insulating board (AIB);
• Manually cutting or drilling AIB;
• Aggressive physical disturbance of asbestos cement (AC), eg breaking or smashing.

 

* The timescales quoted are related to advice given in the previous version of OC 265/48 which stated  that exposure would usually have been insufficient to pose a significant long-term risk to health where Action Levels were not exceeded.  The Action Levels at that time were defined in the Control of Asbestos at Work Regulations 2002 as being 48 fibres per millilitre of air in a continuous 12 week period for all forms of asbestos and mixtures of asbestos, except chrysotile alone, and 72 fibres per millilitre of air in a continuous 12 week period where the exposure was solely to chrysotile.

You may be disturbing ACMs without knowing it and therefore be more at risk than you think. The pattern of your exposure to asbestos is a significant factor in determining the degree of risk.  The following examples illustrate the main patterns of exposure and their relative risk:

Highest risk – carrying out licensable asbestos work (i.e. work with asbestos materials that give off fibres easily) without suitable controls;

• Higher risk – Regularly doing the type of work listed in paragraph 3.2 without suitable precautions in trades such as carpentry, plumbing, electrical, roofing and general maintenance.  Your risk of developing disease is increased because a repeated pattern of exposure over time is likely to cause fibres to build up in your lungs;
• Lower risk – Working in buildings near ACMs in poor condition that are regularly disturbed releasing significant levels of fibres. Your exposure could also be regular, but is likely to be at a lower level than those in paragraphs a) and b);
• Lowest risk – Being in a building when a one-off asbestos incident occurs.  Your risk will be lowest because you are not regularly exposed to asbestos.
• Lowest risk – Being in a building when a one-off asbestos incident occurs.  Your risk will be lowest because you are not regularly exposed to asbestos.

Medical examinations and health records

If you have been involved in an asbestos incident your employer may arrange for you to seek advice from occupational hygienist or an occupational health specialist about the likely exposure levels and associated risks. You are entitled to information about the nature of the incident from your employer and what they have done, or are going to do, to prevent a reoccurrence.

The law does not require your employer to retain health records for those working with asbestos, unless they carry out work licensed by HSE. Health records for employees of licence-holders should be retained for 40 years. 

You may wish to consult your GP so that a note can be made on your personal medical record of the possible exposure including date(s), duration, type of fibre and likely exposure levels (if known). GPs no longer routinely carry out x-ray examinations in relation to asbestos exposure because they can only be used to diagnose disease once it has become established (usually 10-40 years after the exposure).  An x-ray will not show any fibres present in your lungs after an exposure to asbestos.

Further advice and information

For further information about the law relating to asbestos work contact HSE’s Infoline service on Tel: 0845- 345005.

The Council does not deal with compensation or the claiming of benefits. If you think that you or a member of your family is entitled to benefits relating to an asbestos related disease you should contact Job Centre Plus on tel: 0800 279 2322 or speak to an adviser from an asbestos support group in your area.

Information about the current asbestos campaign and practical guidance on controlling exposure (‘Asbestos Essentials Task sheets’) can be found on HSE’s website (http://www.hse.gov.uk/asbestos/essentials/index.htm), along with the following guidance leaflets etc:

1. A short guide to Managing asbestos in workplace buildings (INDG223);  Available at http://www.hse.gov.uk/pubns/indg223.pdf - For those working in building maintenance, repair and refurbishment (available in priced packs of 10).
2. Free Leaflet ‘Manage Buildings? You must manage asbestos’ – A jointly badged leaflet produced by HSE in conjunction with the Trades Union Congress, The Royal Institute of Chartered Surveyors, The Federation of Small Businesses, The Asbestos Testing and Consulting Division of ARCA and The British Institute of Facilities Managers.  Available at http://www.hse.gov.uk/pubns/manageasbestos.pdf
3. INDG 419: ‘Asbestos Kills: Protect Yourself! You are more at risk than you think’ – a new leaflet for maintenance workers.  Available at http://www.hse.gov.uk/pubns/indg419.pdf
4. INDG 418: ‘Asbestos Kills: A Quick Guide to Protecting Yourself’ – A new pocket card for maintenance workers.  Available at http://www.hse.gov.uk/pubns/indg418.pdf
5. Campaign packs produced as part of the HSE’s Asbestos campaign – ‘Asbestos – The Hidden Killer’.  The pack is A5, plastic wrapped and contains the new pocket card (INDG 418) and the new leaflet (INDG 419) for maintenance workers on the risks associated with asbestos.  It also has a promotional flyer for the revised ‘Asbestos Essentials Task Manual’ (INDG 210) and a covering letter.  To order a campaign pack, e-mail HSE Books direct using hsebooks@prolog.uk.com quoting stock code MISC806 or alternatively you can order via HSE’s Infoline tel: 0845 345 0055 and/or via the asbestos webpages  at http://www.hse.gov.uk/asbestos/campaign/orderpack.htm
6. HSG 210 ‘Asbestos essentials Task Manual’ Task Guidance Sheets for the Building maintenance and allied trades (priced publication).
7. HSG 213 ‘Introduction to Asbestos Essentials: Comprehensive guidance on working with asbestos for the building maintenance and allied trades (priced publication).

All are available from:
HSE Books,
PO Box 1999,
Sudbury,
Suffolk,
CO10 6FS
Tel: 01787 881165 or Fax: 01787 313995

Or download/order from www.hse.gov.uk/asbestos

Information Document 3 - Exposure to asbestos from work activities: advice for general practitioners and occupational health professionals

Introduction

This document contains advice following exposure or suspected exposure to asbestos from work activities. People who may have been exposed to asbestos are understandably anxious and concerned about possible effects on their health.

Inhalation of asbestos fibres can eventually lead to a number of diseases, including:

1. asbestosis (an asbestos-induced fibrosis of lung tissue),
2. bronchial carcinoma; and
3. mesothelioma, a rare malignant neoplasm of the pleura or peritoneum.

Asbestosis and bronchial carcinoma in particular  are more clearly linked to high exposure for long periods. There is usually a long delay between first exposure to asbestos and the first symptoms of disease; this can vary between 10 and 40 years, with mesothelioma having a particularly long latency. Much of the current burden of asbestos-related disease (about 4000 deaths per year) is a result of past heavy industrial exposures among those who manufactured and installed asbestos products. HSE is now primarily concerned about potentially frequent and regular exposure patterns arising from direct work with asbestos containing materials (ACMs), e.g. during maintenance activities.  Such exposures could, over time, lead to a substantial accumulation of fibres in the lungs of some workers.

We are all continuously exposed to a low level of asbestos fibres because asbestos was such a widely used material within buildings, machinery, vehicle brakes and homes until 1999, when most forms of asbestos were banned.  The aim of the Control of Asbestos Regulations 2006 is to prevent or reduce additional work-related exposure to asbestos fibres.  However, working directly with asbestos containing materials (ACMs) can give personal exposures to airborne asbestos that are much higher than environmental levels.  Repeated exposures of this type will give rise to a substantial cumulative exposure, thereby increasing the risk of developing an asbestos related disease in the future.

It is unfortunately not uncommon for people to be inadvertently exposed to asbestos fibres during building operations, maintenance work or following damage to asbestos-containing materials. Such incidents understandably cause anxiety about the possible effects, both short and long term, of the exposure. Workers subject to such exposures may consult their GP for advice, and may have unrealistic expectations regarding medical investigations or even treatment. There is at present no effective post-exposure prophylaxis for the effects of inhaled asbestos fibres, although in smokers the risk of asbestos-induced bronchial carcinoma (but not mesothelioma) can be reduced by stopping smoking. There are also no generally available techniques for determining individual lung burdens of asbestos fibres, other than post mortem.

Factors that influence level of risk

It is often difficult to accurately relate specific asbestos exposures to an increased risk of developing disease in the future. The degree of risk will depend on the total life time cumulative exposure; the type of asbestos involved and the time elapsed since the person was first exposed. The degree of cumulative exposure is dependent on the amount of fibres that are generated by the work activity and how long it lasts. The concentration of fibres in the air will be determined by the force used and extent of the disturbance as well as the ability of the ACM to release fibres. The following are examples of work activities likely to create a significant concentration of fibres in the air and thereby add to the risk of developing an asbestos related disease:

• Use of power tools (to drill, cut etc) on most ACMs;
• Physical disturbance, such as knocking, breaking, smashing of a licensable ACM e.g. sprayed coating, lagging, asbestos insulating board (AIB);
• Manually cutting or drilling AIB;
• Aggressive physical disturbance of asbestos cement (AC), eg breaking or smashing.

The pattern of exposure to asbestos is a significant factor in determining the degree of risk.  The following examples illustrate the main patterns of exposure and their relative risk:

• Highest risk – carrying out licensable asbestos work (i.e. work with asbestos materials that give off fibres easily) without suitable controls;
• Higher risk – Regularly doing the type of work listed in paragraph 2.1 without suitable precautions in trades such as carpentry, plumbing, electrical, roofing and general maintenance.  The risk of developing disease is increased because a repeated pattern of exposure over time is likely to cause fibres to build up in the lungs;
• Lower risk – Working in buildings near ACMs in poor condition that are regularly disturbed releasing significant levels of fibres. This exposure could also be regular, but is likely to be at a lower level than those in paragraphs a) and b);
• Lowest risk – Being in a building when a one-off asbestos incident occurs.  The risk will be lowest because exposure is repeated on a regular basis.

Medical examinations

Asbestos-induced radiological changes have a latency almost as long as that for symptom development (ie many years) and therefore a chest X-ray in the early aftermath of even heavy exposure is most unlikely to serve any useful purpose other than acting as a baseline. Similarly, periodic chest X-rays following an inadvertent exposure episode will serve little if any useful purpose in most cases, not least because in the vast majority of cases asbestos-induced disease is irreversible and untreatable by the time it can be diagnosed. However, a holistic view should be taken; clinical judgement may be that in some circumstances a chest X-ray may be of value where there is severe anxiety following asbestos exposure, and that the benefits of this may outweigh the very low level of risk associated with diagnostic X-ray exposures. In such circumstances the benefits and limitations of undertaking a chest X-ray should be explained carefully to the subject.

Further advice

Further advice on cases of this nature can be obtained from chest physicians with an interest in occupational lung diseases and from medical inspectors of HSE's Employment Medical Advisory Service, who can be contacted via HSE’s central advice point Infoline, Tel: 0845 345005.

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