Risk management in connection with offshore oil and gas operations

September 2016

The most important rules on assessing health and safety risks and risks of major environmental incidents as well as reduction of such risks in accordance with the ALARP principle in connection with offshore oil and gas exploration and production.

This guideline includes requirements for assessment of health and safety risks and risks of major environmental incidents, and it describes how such risks should be reduced in accordance with the ALARP principle; referred to collectively as risk management.

The ALARP principle and application of the principle in risk management is described in the DWEA guideline on the ALARP principle in connection with offshore oil and gas operations.

Any mention of installations in the guideline also covers any connected infrastructure.

With regard to transport of an installation or installation components to the offshore assembly site, the guideline only covers risks related to the safety of the future installation. Lifting the installation or installation components from the transport vessels at the assembly site is considered part of assembly work. The operator and the owner, respectively, must ensure that these aspects are included in the risk assessment of the installation.

The same applies to laying of pipelines.

Some parts of the regulations may have a scope that does not include all offshore oil and gas operations. If so, this will be clear from the guideline.

It makes no difference whether a specific mobile installation or an accommodation vessel is registered in Denmark or in another country, or whether the installation or vessel is operated by a Danish or foreign operator or owner. The important factor is that the installation or vessel is operating in Danish territorial waters or continental shelf areas.

The guideline is primarily aimed at those who, according to the Offshore Safety Act, are obligated to ensure that a risk assessment is conducted and that the risks are reduced in accordance with the ALARP principle. These include:

• Licensees
• Operators
• Owners
• Employers
• Enterprise managers
• Offshore installation managers
• Other supervisors
• Other employees

Moreover, the guideline is of interest to the safety organisation on installations, as this should be involved in the company's risk management.

Finally, the guideline may be of interest to consultants and others carrying out risk assessments on behalf of the parties above or advise them in connection with risk reduction.

The most important rules

The main principle of offshore safety legislation is that the operator and the owner, respectively, must reduce health and safety risks and of risks of major environmental incidents in connection with oil and gas operations in accordance with the ALARP principle.

There are three types of risk:

• Risk of major accidents. This covers safety risks and risks of major environmental incidents.
• Other risks. This covers health and safety risks in connection with performance of work and
• layout of the workplace.
• Health and safety risks not related to work. This covers health and safety risks in connection with using the accommodation and other places on the installation.

Risks must be managed throughout the lifecycle of the installation which covers

• design (where relevant),
• operation,
• physical modifications,
• operational modifications, and
• decommissioning (where relevant).

The most important rules on risk management

1. Definitions

1.1 Costs 
1.2 Highest acceptable level of risk 
1.3 Acceptance criterion 
1.4 Generally acceptable level of risk 
1.5 The ALARP region 
1.6 Prevention 
1.7 Workplace assessment

2. General risk management

2.1 General principles 
2.2 Workplace assessment 
2.3 Risk reduction

3. Management of risks of major accidents

3.1 Risk assessment

4. Management of other risks 
4.1 General 
4.2 Substances and materials 
4.3 Noise 
4.4 Vibration 
4.5 Biological agents 
4.6 Artificial optical radiation 
4.7 Electromagnetic fields 
4.8 Musculoskeletal disorders 
4.9 Psychological working environment

5. Management of health and safety risks not related to work

6. Risk management in the different stages of the lifecycle of an installation
6.1 Design of new production installations and fixed non-production installations or major conversion thereof 
6.2 Operation of production installations 
6.3 Decommissioning fixed installations 
6.4 Pipelines 
6.5 Vessels used for accommodation 
6.6 Special vessels 
6.7 Other activities on installations

7. Documentation of risk management

8. Involvement of the safety organisation

1. Definitions

In addition to the definitions described in the DWEA guideline on concepts in connection with offshore oil and gas operations, the following is a series of definitions of concepts used in this guideline.

1.1 Costs

In this guideline, "costs” in connection with risk reduction means costs in terms of money, time and effort associated with reducing the risk.

1.2 Highest acceptable level of risk

Defined as the highest level of risk at which operations may be performed. As a general rule, the risk must be further reduced, see the ALARP principle.

The highest acceptable level of risk can often be measured. If it can be measured, the risk can be expressed as one of the levels mentioned in the definition of safety risk. The highest acceptable level of risk can also be expressed qualitatively, for example through good practice in connection with manual handling of loads.

The legislation stipulates a number of detailed regulations regarding health and safety at work. If these regulations are followed, the risk is considered to be below the highest acceptable level of risk.

For some health and safety aspects, the legislation stipulates an upper limit (limit value) for measurable impacts. For instance, this applies to noise and vibration and to impacts from substances and materials. In such cases, these limit values reflect the highest acceptable level of risk unless the enterprise itself has laid down a lower highest acceptable level of risk.

1.3 Acceptance criterion

Established quantitative limit for the highest acceptable level of risk.

1.4 Generally acceptable level of risk

The risk level at which additional reduction of the risk is unnecessary.

If the risk is found to be at this level or less in connection with a risk assessment, it is not necessary to reduce the risk additionally.

The generally acceptable level of risk can often be measurable. If it can be measured, the risk can be expressed by one of the levels mentioned in the definition of safety risk, see the DWEA guideline on concepts in connection with offshore oil and gas operations.

An example of a non-measurable generally acceptable level of risk is to follow a specific, recognised practice, for example in connection with manual handling of loads.

1.5 The ALARP region

The ALARP region is the risk level between the highest acceptable level of risk and the generally acceptable level of risk. Risk reduction in this region must be carried out in accordance with the ALARP principle, see the DWEA guideline on ALARP in connection with offshore oil and gas operations.

1.6 Prevention

All steps or measures taken to prevent or reduce risks. 
The measures taken to reduce risks according to the ALARP principle must prevent personal injuries or occupational diseases. Prevention is a fundamental principle in both EU legislation and Danish legislation. Annex 1 to this guideline lists in order of priority the principles to be used in connection with reduction of health and safety risks.

1.7 Workplace assessment

An expression originating from the Danish Working Environment Act. A workplace assessment includes an assessment of health and safety concerns and an action plan on how to resolve any workplace health and safety issues, including the risk of major accidents. Absenteeism due to sickness must be included in the assessment. Workplace assessment pursuant to the Working Environment Act corresponds to regulations on risk assessment etc. in the offshore safety legislation.

2. General risk management

2.1 General principles

Risk management consists of the following primary elements:

1. Identification of potential sources of hazard.
2. Assessment of risks from the sources of hazard.
3. Reduction of the risks not generally acceptable according to the ALARP principle.

These elements are described in more detail in standards such as DS/EN ISO 17776 and NORSOK Z-013. Moreover, the British Health & Safety Executive’s (HSE) Offshore Information Sheet No. 3/2006: ”Guidance on Risk Assessment for Off-shore Installations” and the International Association of Drilling Contractors (IADC)’s ”Health, Safety and Environment Case Guidelines for Mobile Offshore Drilling Units” offer useful guidance.

Identification of potential sources of hazard
The first step in risk management is identification of the individual sources of hazard and analysis and evaluation of the risks of such sources of hazard. It is crucial for a reliable risk assessment that all relevant sources of hazard are identified and evaluated.

Assessment of risks from the sources of hazard
The next step is to assess the risks that might arise from the sources of hazard, including whether the individual risks are generally acceptable in terms of health and safety.

Reduction of risks not generally acceptable 
Where the risks are not generally acceptable, see definition above, the risks must be eliminated or reduced to a level in the ALARP region in accordance with the ALARP principle.

The standards and guidelines above include more detailed descriptions of hazard identification and risk assessment, see for example DS/EN ISO 17776, Annex B.

Where appropriate, the risk assessment must be carried out using qualitative, semi-quantitative or quantitative methods or a combination of the three, see the aforementioned DS/EN ISO 17776 standard. Quantitative methods should generally only be used where the database and the assessment criteria make this relevant. For example, risk reduction according to the ALARP principle can be supported by a quantitative assessment in order to establish any disproportionality between additional risk reduction and the costs of the reduction. This will typically be relevant in connection with risks with a low likelihood and less serious consequences.

When applying quantitative methods, uncertainties in the database used must be stated and included in the assessment.

Qualifications 
Throughout the process, it is crucial that those conducting the assessments possess the necessary skills. Skills requirements must be established in the management system of the operator and the owner, respectively. Furthermore, it is crucial that employees are involved in the assessment and the subsequent risk reduction. This should be in accordance with the rules on cooperation concerning health and safety, see the DWEA guideline on this.

2.2 Workplace assessment

Where the concept of workplace assessment is applied, the Health and Safety Document (also known as a Health and Safety Case (HSC)) for the installation must state the part of the risk management covered by the workplace assessment and how the company manages the risks that are not covered by the workplace assessment.

2.3 Risk reduction

General 
Risk is the combination (the product) of the likelihood and consequences; i.e. in order to reduce the risk, it is necessary to focus on reducing the likelihood that the hazardous events occur and on reducing the consequences of events if such events do occur. For health risks, it is necessary to focus on reducing the degree of exposure (concentration, dose) as well as the duration of exposure.

The following general hierarchy for risk reduction should be applied, see, for example, DS/EN ISO 17776:

1. Prevention (elimination or reduction of the likelihood that potentially hazardous events occur).
2. Detection (transmission of information to a control point).
3. Control (systems that control a hazard to minimise or remove consequences).
4. Protection (technical mitigation of consequences of a hazardous event).
5. Emergency response (fire fighting crew, escape, evacuation and rescue (EER)).

In accordance with the ALARP principle, safety must be incorporated into the installation using one or more of the following design principles:

• Reduction (reduce the size of sources of hazard or the frequency or duration of exposure).
• Substitution (replace hazardous activities, substances or materials with less hazardous ones).
• Limitation (use of hazardous materials or processes in such a manner that limits their hazard potential, such as separating processing plants into smaller units using ESD valves, or carrying out the process at a lower temperature or pressure).
• Simplification (simplified design, construction and operation of processing plants to reduce the risk of equipment and control errors as well as human errors).

Preventive measures must be assessed before considering protective measures. Protective measures aim at mitigating effects (consequences) of a potential hazardous event when such event has occurred. Protective measures may be fire and gas detection systems, fire water mains, active and passive fire and explosion protection, temporary refuge, evacuation systems, equipment and procedures to recover oil, and protective equipment. Then the emergency response must be assessed.

Where the effects of a hazardous event are major, protective measures should always be considered, even though the likelihood of the event is small.

Choice of risk reduction measures will be influenced by

• technical feasibility, 
• the impact of the measures, 
• the costs and risks of implementing the measures, and 
• the degree of uncertainty when assessing the risk or the method to reduce the risk, including human factors.

A risk reduction measure must be implemented in accordance with the ALARP principle.

Norms and standards 
If they exist, recognised norms and standards must be followed when risk reduction covers design, choice of equipment, or operational measures. Deviations may only take place if they result in a lower risk than that resulting from applying the norm or the standard.

Preparation of norms and standards by international standardisation organisations is a time-intensive process. In some cases, technical developments could therefore result in norms and standards being difficult to apply on the most modern equipment and work methods, or that application does not enable the solutions that reduce the health and safety risks in accordance with the ALARP principle.

Consequently, considerations should always include whether additional risk reduction pursuant to the ALARP principle is possible after choosing a given standard.

Choice of norms and standards must be included in the Health and Safety Document for the installation.

When choosing a norm or standard, the operator or the owner should primarily use EU harmonised standards where such exist. This will ensure compliance with the regulations implementing associated directives, and reference can be made to these when documenting compliance. Existing harmonised standards are mentioned on the Danish Standards Association website.

Where appropriate harmonising standards do not exist, the operator must choose other recognised standards if such exist for the specific application. The following standards are generally considered by the Danish Working Environment Authority (DWEA) as recognised:

• EN (European Standard). 
• ISO (International Organisation of Standardization). 
• IEC (International Electrotechnical Commission). 
• API (American Petroleum Institute). 
• Other, similarly widespread standards; i.e. in the European Union and globally.

In addition, the DWEA will consider the following standards and conventions for specific areas as recognised standards:

• IMO (the UN International Maritime Organization)
• ICAO (International Civil Aviation Organization)
• IALA (International Association of Marine Aids to Navigation and Lighthouse Authorities).

Furthermore, the DWEA will consider other norms and standards as recognised if these are mentioned specifically in Executive Orders under the Offshore Safety Act. In this case, these norms and standards must be followed, but can be derogated from, see above. Where there is just a reference to the standards that can be used, there is no obligation to follow these standards, but they will serve as a good foundation for achieving good practice and thus a basis for complying with the ALARP principle. Such standards may include:

• NORSOK (industry standards for the Norwegian continental shelf). 
• Standards from ASME (American Society of Mechanical Engineers). 
• Guidelines from the EEMUA (Engineering Equipment and Materials Users Association, British organisation). For example, EEMUA 191 - Alarm Systems. 
• Standards from the NFPA (National Fire Protection Association, USA).
• Standards from the IEEE (Institute of Electrical and Electronics Engineers), international organisation.
• Standards issued by recognised classification societies.

The list of norms and standards is not meant to be comprehensive and should not be taken as such. The different sections in the guideline may mention specific standards considered as recognised by the DWEA, but which are not mentioned above.

If several standards each contain requirements for the same health or safety aspect, a standard must be chosen taking into account the ALARP principle.

3. Management of risks of major accidents

3.1 Risk assessment

The assessment of risks of major accidents must be performed in accordance with approved risk assessment methods. Approved methods are primarily considered methods established in recognised norms and standards, such as DS/EN ISO 17776 or NORSOK Z-013. Other approved methods are also acceptable.

The British Health & Safety Executive (HSE) has published a guide on risk assessment of installations. The guide is available on the HSE website.

The International Association of Drilling Contractors (IADC)’s Health, Safety and Environment Case Guidelines for Offshore Drilling Contractors (MODUs) referred to above contains a section on risk management.

The operator must laid down acceptance criteria for risks of major accidents in connection with design, operation and modification of the production installation. The same requirements apply to the owner of non-production installations and pipelines. For mobile non-production installations, the requirement only applies in connection with operation and modification of the installation.

The DWEA will not approve the acceptance criteria, but will assess whether they are reasonable based on good practice.

The acceptance criteria must be established for the individual risk as well as for the collective risk, see definitions in the DWEA guideline on concepts in connection with offshore oil and gas operations.

Establishment of acceptance criteria is only used to determine when the activity can be carried out. In addition, additional risk reduction must always be carried out in accordance with the ALARP principle.

The NORSOK standard Z-013 includes guidelines on how to establish acceptance criteria.

Although the operator and the owner, respectively, does not have to establish acceptance criteria for other risks, the limit values laid down in the legislation and recognised standards will be considered as acceptance criteria. This applies to noise, vibration and substances, for example.

The risk assessment must subsequently be updated if any material modifications are made to the installation or the pipeline. Modifications may be extension of platforms, increase in the number of wells, and modification to processing plants and to operational conditions on the installation, including changes in manning in relation to the requirements applied.

The DWEA guideline on approvals and permits describes in more detail what are regarded as material modifications.

In connection with updating the risk assessment, a reassessment of the risk reduction measures must be carried out using the ALARP principle.

Evacuation analysis 
An evacuation analysis must be carried out for the installation before it is put into operation, and the analysis must be documented in the Health and Safety Document for the installation.

Furthermore, an evacuation analysis must be carried out prior to any manning of the installation before it is put into operation, for example during hook-up and commissioning, or before it is manned during decommissioning.

An evacuation analysis is a systematic examination of events that could occur when a potentially dangerous situation arises in which evacuation may be necessary.

The evacuation analysis must be prepared on the basis of the risk assessment for major accidents. On the basis of this, the potential accident scenarios must be described. These scenarios will form the basis of mapping the possibility of escaping to a safe location for the persons on board, with subsequent evacuation and rescue to a safe location if the dangerous situation escalates.

There are a number of requirements for the evacuation analysis:

The evacuation analysis must be performed according to recognised methods and the following must be included as a minimum in the analysis:

1. Based on the risk assessment, determination of the situations in which evacuation is necessary.
2. Assessment of escape options in the situations mentioned in point 1.
3. Assessment of options for efficient and controlled evacuation of the installation in the situations mentioned in point 1.
4. Assessment of options for efficient rescue to a safe location after the evacuation.
5. Establishment that the risk of not being able to evacuate and rescue people to a safe location has been reduced in accordance with the ALARP principle. "A safe location" means a location where people are no longer exposed to danger or risks from the critical situation which caused the evacuation and rescue, and where medical treatment and, if required, transport to shore is possible.

The evacuation analysis must be documented in the Health and Safety Document together with the risk assessment.

The evacuation analysis must be updated if there are material changes in the conditions that form the basis of the analysis.

"Recognised methods" primarily means methods described in recognised norms and standards, for example ISO standards. This also means methods described in NORSOK standards or guidelines from the authorities regulating offshore safety.

An independent verification of the evacuation analysis must be carried out. This applies to new evacuation analyses as well as to existing evacuation analyses updated in connection with material changes in the conditions that form the basis of the analysis.

Among other things, verification must verify that the analysis has been carried out according to recognised methods and contains the five elements mentioned above.

The operator or the owner must ensure that the independent verification is carried out in accordance with the regulations. 

4. Management of other risks

4.1 General

Other risks typically originate from the following health and safety conditions:

• Physical conditions: For example, the work room, surroundings, noise, indoor climate, vibration and optical radiation and lighting.
• Ergonomics: For example, manual lifting, repetitive tasks and work postures. 
• Psychological conditions: For example, time pressure, repetitive monotonous work, influence and working alone. 
• Chemical conditions: For example working with substances and materials. 
• Biological conditions: For example, bacteria, viruses and fungi. 
• Risks of accidents: For example, from machinery, hand tools, passage, handling, fire and explosion.

Such risks are also mentioned in section B.8 of the DS/ISO 17776 standard.

Such risks must be identified, assessed and reduced according to the ALARP principle, and the result must be incorporated into the design of new production installations and fixed non-production installations as well as in the operation of all types of installation in order to comply with the ALARP principle. In the design phase, the type of permanent workstations to be established on the installation is typically known. For each of the workstations, the health and safety conditions above must be assessed, such that preventive measures can be incorporated into the design. When awareness of the working conditions increases, a similar assessment of the temporary workstations on the installation must be carried out.

Analysing health and safety issues (identification of risks) may take place through:

• Interviews with employees. 
• Round tables.
• Employee satisfaction surveys. 
• Questionnaires, for example electronic.
• Use of checklists from the DWEA. 
• Use of material from sector working environment councils. 
• Use of technical assessments, including measurements. 
• Statistics/reports on accidents

Furthermore, an assessment of employee absenteeism due to sickness must be included to identify any correlation with health and safety at work.

Help to assess health and safety conditions, including absenteeism due to sickness, is described in the DWEA guideline on workplace assessments.

Employees must be involved in all stages of risk management. In order to meet the requirement in the regulations for identification of other risks, an expert may need to carry out an assessment of the health and safety risks. An expert can be an internal person in the enterprise. However, if such expert does not exist, the enterprise may use outside expert knowledge. The technical assessments mentioned above will typically be part of the overall assessment. Risks, such as ergonomic risks, cannot always be measured directly, and assessment of such risks must be carried out on the basis of expert knowledge about harmful influences.

This applies in particular to requirements for the assessment of risks from impacts from substances and materials, including asbestos and other carcinogenic substances, biological conditions, noise, vibration, optical radiation and electromagnetic fields, see below.

A distinction is drawn between permanent workstations and non-routine work on temporary workstations. The latter will typically be subject to work permits or a so-called Safe Job Analysis (SJA) which is a "snapshot" assessment of health and safety risks related to work, see also Annex B, point B.4 of DS/EN ISO 17776, for example. In work using large equipment, perhaps where independent workstations are brought to the installation, prior to arriving at the installation, the equipment must have been subject to relevant assessments and improvements regarding the equipment itself as well as its interaction with the installation. When using such equipment, a Safe Job Analysis or similar is therefore not adequate. Examples of such equipment include coiled tubing equipment used in operations in production wells and cementing equipment on drilling rigs.

4.2 Substances and materials

Assessment of risks relating to substances and materials must be based on the following elements:

1. The hazardous properties of the substances and materials as stated on the packaging and the related safety data sheets from the supplier.
2. Information from the supplier on health and safety as set out in the safety data sheet from the supplier.
3. The level of exposure, type and duration.
4. The conditions of work with hazardous substances and materials, including the quantity, i.e. the layout of the workplace and the performance of work.
5. Limit values. For details see the DWEA list of limit values.
6. The effect of the preventive measures that have been taken or are to be taken.
7. Where possible, the conclusions to be drawn from the occupational health assessments.

Where it is necessary to be able to establish the risk, additional information must be obtained from the supplier of substances and materials.

The documentation of the risk assessment, see section 7, must also contain an inventory of the hazardous substances and materials used, with reference to the safety data sheet from the supplier. This information is often gathered in a chemicals manual, and this can be referred to in the documentation.

Where it can be documented that the nature and scope of impacts from substances and materials are insignificant, and that preventive measures therefore are not necessary, not all of the elements mentioned in points 1-7 have to be included. An example of this is substances and materials in closed systems which therefore are not released to the surroundings during normal operation. However, a risk assessment must be carried out in connection with any unintended release to the surroundings, and suitable measures must be taken to prevent releases and limit the consequences of any releases pursuant to the ALARP principle.

Exposure to hazardous substances and materials must be eliminated or reduced to a minimum in connection with use through, in order of priority:

1. Eliminating, replacing or reducing the quantity of hazardous substances and materials to the minimum required for use. 
2. The design of the installation. 
3. Use of equipment.
4. Reducing to a minimum the number of employees exposed or likely to be exposed to hazardous substances and materials.
5. Suitable working procedures, including arrangements for the safe handling, storage and transport within the workplace of hazardous substances and materials.

Where the solutions mentioned in points 1-5 do not sufficiently reduce the risk, or cannot be applied due to the nature of the work, appropriate personal protective equipment must be used.

The aim must always be substitution with less hazardous substances or materials, irrespective of whether exposure to substances or materials is insignificant. If substitution is not feasible, this must be explained in the documentation of the risk assessment.

As part of the risk reduction, the operator or the owner must prevent the presence at the installation of hazardous concentrations of inflammable substances or materials or hazardous quantities of chemically unstable substances or materials. Where the nature of the work does not allow that, the presence of ignition sources which could give rise to fires and explosions must be avoided. Adverse conditions which could cause chemically unstable substances or materials to give rise to harmful physical effects must also be avoided.

The operator or the owner must take measures to mitigate the detrimental effects in the event of fire or explosion due to the ignition of inflammable substances or materials, or harmful physical effects arising from chemically unstable substances or materials. Such measures must be stated in the internal emergency response plan for the installation.

Specific considerations for work with asbestos or asbestos-containing products

When working with asbestos, specific requirements exist for the layout of the workplace and for use of personal protective equipment to reduce the risk from exposure to asbestos-containing dust as much as possible.

Specific considerations for work with carcinogenic substances or materials
When working with carcinogenic substances or materials, specific requirements exist for the layout of the workplace, depending on the substance or material used, to reduce the risk from exposure to the substances or materials as much as possible.

Specific considerations for work with paints etc.
In order to reduce the risk according to the ALARP principle, painting and work with adhesives and fillers and sealants require substances and materials to be labelled with a code number. This labelling is subject to specific safety requirements. More information about painting buildings is available in the DWEA guideline on product choices for painting buildings.

In addition to the requirements for the painting mentioned above, work with epoxy resins and isocyanates requires specific measures to be taken when designing the workplace, and special training is required.

Requirements for painting etc. have been described in detail in the Executive Order on the Use of Substances and Materials in connection with Offshore Oil and Gas Operations. Since the offshore regulations correspond to onshore regulations, information is also available in the DWEA guideline on product choices for painting buildings, in the DWEA guideline on measures in connection with primary exposure to epoxy resins and isocyanates and in the DWEA guideline on secondary exposure to isocyanates.

4.3 Noise

The employees' level of exposure to noise must be assessed and possibly measured as part of the risk assessment. The risk assessment must consider:

1. The level, type and duration of noise exposure, including any exposure to impulsive noise.
2. The limit values and action values for noise exposure.
3. Negative effects concerning the health and safety of employees belonging to particularly sensitive risk groups.
4. Nuisance noise, i.e. noise that is not damaging to hearing, but which may impair the mental or physical health of employees.
5. Any effects on the employee's health and safety resulting from interactions between noise and work-related substances that may damage the ear or hearing when absorbed by the organism, and between noise and vibrations, in so far as is technically possible.
6. Any indirect effects on employees' health and safety resulting from interactions between noise and warning signals or other sounds that need to be observed in order to reduce the risk of accidents.
7. Information on noise emission provided by manufacturers of equipment in accordance with the relevant EU directives.
8. The existence of alternative equipment designed to reduce noise emission.
9. The extension of exposure to noise beyond normal working hours in connection with activities under the employer's responsibility. 
10. The results of occupational health assessments which give rise to new measures.
11. The availability of hearing protectors with adequate attenuation characteristics.

The limit value of 83 dB(A) in a 12-hour working period is considered an acceptance criterion for noise exposure. Therefore, noise exposure levels must be reduced according to the principles arising from the noise regulations in compliance with the ALARP principle. This means primarily technical solutions, then reduction of daily working hours (administrative measures), or a combination of the two. If the solutions above cannot reasonably be applied, or do not adequately reduce noise exposure levels, suitable individual hearing protectors must be used. More information about noise is available in the DWEA guideline on noise.

4.4 Vibration

If it is assessed that employees may be exposed to harmful vibration, the risk assessment must also contain an assessment, and if necessary a measurement, of the employees' daily vibration exposure.

Measurement of vibration must be carried out to the extent necessary in order to clarify exposure. As an alternative to measurement, vibration exposure can be assessed through observation of the specific work method and on the basis of information about the vibration strength of the equipment under the given working conditions.

The documentation of the risk assessment must state the measurements or other assessments.

The risk assessment must consider:

1. The level, type and duration of vibration exposure, including any exposure to intermittent vibration or repeated shocks. 
2. The limit values and action values for vibration exposure. 
3. Negative effects concerning the health and safety of employees belonging to particularly sensitive risk groups. 
4. Any indirect effects on employee health and safety resulting from interactions between mechanical vibration and the workplace or other work equipment, in particular where the mechanical vibration 
   interferes with the proper handling of controls or reading of indicators, or 
   interferes with the stability of structures or joints. Information provided by the manufacturers of equipment in accordance with the relevant EU Directives.
5. The existence of replacement equipment designed to reduce the levels of exposure to mechanical vibration.
6. The extension of exposure to whole-body vibration beyond normal working hours in connection with activities on the offshore installation etc., including vibration exposure during use of accommodation facilities. This means vibration which cannot be controlled by the employees themselves, e.g. vibration in the accommodation as a result of machinery etc.
7. Specific working conditions such as low temperatures. 
8. The results of occupational health assessments which give rise to new measures.

Alternatively, an assessment may include a justification by the employer that the nature and extent of the risks related to mechanical vibration make a further detailed risk assessment unnecessary.

The daily exposure limit value for hand-arm vibration at 4.1 m/s² and for whole-body vibration at 0.94 m/s² in a reference period of 12 hours is considered an acceptance criterion. Thus employees may not carry out a task if the exposure exceeds these values. Measures must be introduced to reduce the risk in accordance with the ALARP principle at vibration exposure levels exceeding the action value at 2.05 m/s² and 0.41 m/s², respectively, see figure below.

When selecting measures, the following must be taken into account:

1. Other working methods which reduce vibration exposure. 
2. The choice of appropriate work equipment of appropriate ergonomic design and, taking account of the work to be done, producing the least possible vibration. 
3. The provision of technology that reduces the risk of injuries caused by vibration, such as seats that effectively reduce whole-body vibration and handles which reduce the vibration transmitted to the hand-arm system.
4. Maintenance plans for work equipment and the workplace. 
5. Design, layout and location of work stations. 
6. Adequate information, instructions and training of employees to use work equipment correctly and safely in order to reduce their exposure to vibration to a level as low as reasonably practicable. 
7. Limitation of the duration and intensity of the exposure. 
8. Appropriate work schedules with adequate rest periods.
9. The provision of clothing to protect exposed employees from cold and damp. Warm clothing reduces the risk of "white-finger" sickness, even though it does not reduce the vibration exposure level.

4.5 Biological agents

The risk assessment must include determination and assessment of the nature, degree and duration of exposure to biological agents and the risk involved. The assessment must be carried out on the basis of the classification of biological agents, and otherwise in accordance with the guidelines below.

Examples of activities on installations that may involve exposure to biological agents:

1. Activities where there is contact with products of animal origin. 
2. Work in treatment rooms and in connection with first aid.
3. Work in connection with collection, treatment and disposal of waste, including household refuse. 
4. Work in sewage purification installations. 
5. Activities in rooms with air humidifier systems.
6. The use of standing insufficiently heated service water (Legionella pneumophilia). 
7. Activities in places with mould.

General conditions 
The risk assessment must be conducted on the basis of all available information, including in particular:

1. Classification of biological agents. 
2. Information on potential allergenic or toxigenic risks as a result of exposure to biological agents, whether or not the biological agent belongs to risk group 1 according to the classification above, or whether the biological agent belongs to groups 2, 3 or 4, and in addition to posing a risk of infection poses an allergenic or toxigenic risk.
3. Guidelines from a public authority, including the DWEA or the Danish Health Authority, on how to control the individual biological agent to protect employee health and safety.
4. Knowledge of a disease which may be contracted as a result of an activity, or from which an employee is found to be suffering and which has a direct connection with this activity. 
5. Knowledge of an activity during which exposure to biological agents may take place in order to determine the degree and duration of any exposure.

Special conditions in connection with treatment of individuals regarding known or suspected disease and injury
As regards treatment of individuals, the risk assessment must pay particular attention to:

1. Uncertainty about the presence of biological agents in human patients and the materials and specimens taken from them.
2. The hazard represented by biological agents possibly known or suspected to be present in human patients and materials and specimens taken from them. 
3. The risks posed by the nature of the work, including blood sampling, for example.

4.6 Artificial optical radiation

When preparing the risk assessment, the operator or the owner must pay particular attention to the following: 

1. The level, wavelength range and duration of exposure.
2. Limit values.
3. Any effects concerning the health and safety of employees belonging to particularly sensitive risk groups.
4. Effects on employee health and safety resulting from interactions between artificial optical radiation and chemical substances influencing light sensitivity.
5. Indirect effects such as blinding, explosion or fire.
6. The existence of replacement equipment designed to reduce the levels of exposure to artificial optical radiation.
7. Appropriate information obtained from health surveillance, including published information, as far as possible.
8. Multiple sources of exposure to artificial optical radiation.
9. Laser equipment with a classification defined in accordance with the relevant IEC standard and artificial sources likely to cause damage similar to that of a laser of class 3B or 4 in any similar classification.
10. Information provided by the suppliers of optical radiation sources and associated equipment in accordance with relevant EU directives. 

Measurements or calculations must be carried out to the extent necessary in order to clarify risks.

In connection with assessment and calculations, the method used must follow the standards of the International Electrotechnical Commission (IEC) in respect of laser radiation and the recommendations of the International Commission on Illumination (CIE) and the European Committee for Standardisation (CEN) in respect of non-coherent radiation.

In exposure situations which are not covered by these standards, assessment, measurement or calculations must be carried out in accordance with available science-based guidelines. The assessment may take account of data provided by the suppliers of the equipment when the equipment is covered by relevant EU Directives.

The operator and the owner, respectively, must ensure that physicians, occupational health clinics and health authorities responsible for occupational health assessments have access to the risk assessment when relevant for health surveillance.

Where the risk assessment indicates a risk that the limit values may be exceeded, the operator and the owner, respectively, must plan and implement technical or organisational measures or a combination of the two, designed to prevent the exposure exceeding the limit values, taking into account in particular:

1. Alternative methods that reduce the risks from artificial optical radiation. 
2. The choice of equipment that reduces optical radiation, taking account of the activity to be done.
3. Technical measures to reduce the emission of artificial optical radiation, including the use of interlocks, shielding or similar health protection mechanisms.
4. Appropriate maintenance programmes for equipment, workplaces and other places where artificial optical radiation may occur. 
5. The design and layout of workstations and other places on the offshore installation where artificial optical radiation may occur.
6. Limitation of the duration and level of the exposure.
7. The availability of appropriate personal protective equipment.
8. The supplier's instructions for the equipment.

See also the DWEA website for recommendations regarding work on arc welding, ultraviolet lamps and lasers of hazard class 3B or 4.

4.7 Electromagnetic fields

Guidelines on managing risks from electromagnetic fields are available in the European Commission publication "Non-binding guide to good practice for implementing Directive 2013/35/EU Electromagnetic Fields".

4.8 Musculoskeletal disorders

Guidelines on prevention of musculoskeletal disorders are available (in Danish) in the DWEA guideline on work-related musculoskeletal disorders.

4.9 Psychological working environment

Guidelines on how to include the psychological working environment in the risk assessment are available (in Danish) in the DWEA guideline on analysing the psychological working environment.

5. Management of health and safety risks not related to work

As employees live on the installation, aspects relating to leisure time may also present a health and safety risk. The operator and the owner, respectively, must therefore make sure that such risks are also assessed and reduced according to the ALARP principle.

The health and safety risks may be the same as those mentioned in the section on other risks and should be dealt with in the same manner. In addition, there may be health risks relating to hygiene, drinking and service water quality, indoor climate in the accommodation facilities and the effect of tobacco smoke. Furthermore, welfare conditions in leisure time may have an impact on mental and physical health.

6. Risk management in the different stages of the lifecycle of an installation

6.1 Design of new production installations and fixed non-production installations and major conversion thereof

When designing new production installations and fixed non-production installations or in connection with major conversion of such installations, the operator must identify all risks and risk reduction measures in accordance with the ALARP principle. This means that the risk reduction measures must be incorporated into the design. The stage from choice of concept to detailed design with specification, drawings, calculations, etc. offers ample room for incorporating risk reduction measures at considerably lower costs seen in relation to the costs of subsequent establishment of risk reduction measures.

This applies to risks of major accidents and other risks as well as health and safety risks not related to work.

All aspects of the future operation must be regarded, including transport to and from the installation. Where, on installations without additional accommodation capacity, it becomes necessary for a period to base extraordinary maintenance and execution of modification projects on daily transport of individuals from other installations, this must be included in the assessment.

The design must give due consideration to needs arising in future to expand the installation's capacity and function, such as larger process equipment and space for additional equipment in connection with later water or gas injections into the field from where the installation produces. Taking account of the installation's design life, for example, it must be endeavoured to use the best technology possible.

Design includes:

• The overall design of the installation or parts thereof (concept).
• The design of details of the installation, equipment and systems, including process and auxiliary systems. 
• Layout of workstations and accommodation facilities.

When choosing the design, the operator must follow the principles for managing the health and safety risks mentioned in sections 3, 4 and 5, which include

a) choice of the design solution that overall involves the lowest risk, or 
b) demonstration that rejection of design solutions with the lowest risk is in accordance with the ALARP principle.

The overall risk assessment and choice between different risk reduction measures must take into account the expected lifecycle of the installation, including construction, assembly, operation, maintenance and modifications (to the extent possible) as well as decommissioning and disposal. It may be useful to balance risks between different stages in the lifecycle to obtain the safest overall solution.

Non-permanently manned installations 
When designing and laying out non-permanently manned installations, the typical choice will be a simple solution, such that much of the equipment that exists on permanently manned installations is left out. All things being equal, the risk of major accidents will thus be higher than on permanently manned installations. This will be compensated for as the installation will normally be unmanned, such that the number of hours the installation is manned is reduced to a level as low as reasonably practicable. Therefore, when designing installations, it should be considered how often and by how many individuals the installation is to be manned, and this must be included in risk management. These considerations should also include choice of life-saving appliances laid down on the basis of the evacuation analysis.

In addition to the risk of major accidents, there are other risks related to access to the installation and to work on the installation when manned. These risks must be covered by risk management. For instance, employees may be injured when accessing the installation via boat, and the same risks resulting from the design and layout of the workplace are present as those mentioned in section 9 (Management of other risks).

6.2 Operation of production installations

The operator must conduct an assessment of health and safety risks and of risks of major environmental incidents of operating a production installation and reduce such risks in accordance with the ALARP principle. This also applies in connection with planned modifications to the installation.

Health and safety risks in connection with operation are the risks to which employees are exposed in connection with offshore work, i.e. from the time they arrive at the onshore site from where transport to the installation takes place until they begin their day off.

Such risks are:

1. Risks in connection with transport between the installation and shore as well as between installations, irrespective of whether transport is by helicopter or ship.
2. Risks relating to the construction of the individual installation. 
3. Risks relating to combined operation between several offshore installations, for example combined drilling rigs and production installations.
4. Risks in connection with performance of work as well as with staying on the installation during working hours and rest periods.

The measures taken to reduce health and safety risks may not impose expenses on employees. For example, the employer must pay for personal protective equipment and work clothing.

It is not sufficient only to carry out a risk assessment and associated risk reduction before the installation is put into operation. Continuous risk management must be carried out according to procedures laid down in the management system of the operator. For example, near misses, industrial accidents or sickness absence may require that new measures be introduced to reduce the risk. Moreover, new knowledge may require new measures. Finally, the risk assessment must be updated when changes are made to health and safety conditions on the installation that may result in an increased risk of accidents and occupational diseases.

In addition to the operator, the individual employers must assess the risk of the assignments for which they are responsible. At the same time, measures to reduce risks must be coordinated through cooperation with the operator and the other employers. In such cases, risk management may be through a work-permit system that may be supplemented by other initiatives. Measures to reduce the risk must be taken before commencement of work.

Non-permanently manned production installations 
In the operation of non-permanently manned production installations, such installations will occasionally need to be manned in connection with planned maintenance and repairs of equipment etc.

The risks that may occur when manning such installations may result from transport to the installation, including weather conditions when accessing the installation from a boat, and the risk of major accidents and other risks when working on the installation, including light conditions. Other risks may be relevant in connection with water quality, hygiene etc. and must also be assessed and any problems must be solved.

Reduction of risks will include measures on the actual installation and observation of weather conditions in connection with access and evacuation. Risks can also be reduced by limiting the time spent at the installation; i.e. a combination of the number of visits and the duration of each visit. Furthermore, minimising the number of persons on the installation will limit the number of persons exposed to an incident if an incident occurs. Therefore, the number of persons visiting the installation and the duration of visits must be set in order to reduce the risks in accordance with the ALARP principle.

Mobile non-production installation operation and modification 
When an operator enters into an agreement on using a mobile non-production installation (a drilling rig, for example), the operator must ensure that all health and safety risks and risks of major environmental incidents are reduced in accordance with the ALARP principle. This applies to risks originating from the construction, layout, equipment and operation of the installation.

Valid certificates issued by the flag state or a certified classification society on behalf of the flag state are sufficient documentation that the areas of the installation covered by the certificates meet the requirements. This can be ensured by the operator carrying out an audit of the owner of the installation who is obligated to manage health and safety risks as well as risks of major environmental incidents through his management system.

The owner is subject to the same requirements as the operator of a production installation for operation of a mobile non-offshore installation, see section 6.1.

When planning modifications to a mobile non-production installation while in operation on Danish territory, the owner will have the same obligation to manage health and safety risks and risks of major environmental incidents as the operator has in connection with modifying the production installation.

Health, Safety and Environmental Case Guidelines for Mobile Offshore Drilling Units are available from the International Association of Drilling Contractors (IADC).

6.3 Decommissioning fixed installations

Decommissioning a fixed installation must be planned and carried out so as to ensure that the health and safety risks and risks of major environmental incidents connected with the work are identified, assessed and reduced in accordance with the ALARP principle. The operator is responsible for this and must manage the risks through his management system. The company performing the actual work is responsible as a contractor and as an employer.

6.4 Pipelines

The same requirements for management of safety risks apply for pipelines as for fixed installations.

6.5 Vessels used for accommodation

In terms of risks, accommodation on a vessel associated with an installation is considered part of the installation; i.e. management of health and safety risks by the operator or the owner must also cover health and safety for the employees while accommodated on the vessel. In this connection, the operator or the owner must obtain the necessary information from the owner of the vessel and enter into agreements with the owner of the vessel regarding health and safety concerns.

6.6 Special vessels

The responsibility for managing health and safety risks and risks of major environmental incidents arising from activities carried out by special vessels operating at associated installations lies with the operator and the owner, respectively, responsible for operating the associated installation.

Special vessels, such as crane vessels, stimulation vessels and well-intervention vessels, are not considered as separate installations when operating in connection with an installation.

Stimulation vessels and well-intervention vessels not operating in connection with an installation are considered installations in themselves, and the same rules apply to such vessels as for mobile non-production installations, both regarding division of responsibility and management.

For crane vessels used to assemble fixed installations, the operator is responsible for managing the risks associated with the assembly activities and the risks related to safety on the future fixed installation.

6.7 Other activities on installations

If, simultaneously with offshore oil and gas operations, installations are used for other operations such as storage of CO₂, the risks associated with such other operations must be included in the risk management for the installation as described for production installations and mobile non-production installations.

7. Documentation of risk management

Assessment of risks of major accidents, other risks and health and safety risks not related to work, as well as proof that risks have been reduced in accordance with the ALARP principle must be documented in the Health and Safety Document for the installation. The documentation must, as a minimum, include:

1. The standard or norm used to assess risks of major accidents, possibly with references, or, in the absence of such standard or norm, method for risk assessment and a clear description of the assessment criteria for risk management, including uncertainty factors in the assessment. 

2. That risk management has taken into consideration all relevant stages in the lifecycle of the installation and all foreseeable situations including:
a) how the design decisions described in the design notification have taken account of risk management so as to ensure inherent safety and environmental principles are incorporated, 
b) how well operations are to be conducted from the installation when operating, 
c) how well operations are to be undertaken and temporarily suspended before production is commenced from a production installation, 
d) how any combined operations are to be undertaken with other installations, and 
e) how any decommissioning of the installation is to be undertaken.

3. Risk management such as 
a) identification of potential sources of hazard associated with the activities, including any activity related to the installation and its decommissioning, where relevant, and which is likely to have serious consequences for the health and safety of employees. Moreover, the documentation must contain an overview of fixed and temporary workstations on the installation, and the extent to which the potential sources of hazard in sections 3, 4 and 5 are present at these stations, 
b) determination of the maximum manning on the installation and the minimal manning necessary to ensure operation of the installation, 
c) assessment of health and safety risks and risks of major environmental incidents from each of the potential sources of hazard mentioned under point a), 
d) an overview of the safety and environmental critical elements on the installation, 
e) a report from an independent verifier. The report must show that the safety and environmental critical elements identified under point d) meet their objective. Moreover, the report must show that the time schedule for examining and testing safety and environmental critical elements is in accordance with the rules laid down in the management system of the operator or the owner for health and safety. Finally, the report must show that the time schedule has been updated and works properly, and 
f) demonstrate that the risks mentioned in point c) have been reduced in accordance with the ALARP principle.

4. A report from an independent verifier, verifying that an evacuation analysis has been carried out in accordance with recognised methods and based on the risk assessment, see point c), and that the evacuation analysis ensures controlled and effective evacuation and rescue to a safe location.

5. That the measures and arrangements for the detection of an emergency situation, and the rapid and effective response to this, are clearly identified and proven suitable. 

6. As regards other risks during operation of the installation and health and safety risks not related to work, the documentation must demonstrate the following: 
a) Priorities and an action plan to reduce the health and safety risks which cannot be reduced immediately. The plan must state in what order and when the ascertained risks are to be reduced. 
b) Inclusion of absence due to sickness to assess whether health risks on the installation may lead to absence due to sickness.

In order to identify the potential sources of hazard and assess the associated risks, it is essential that the necessary professional skills are present in the individual team member carrying out the identification and in the team as a whole. The management system for health and safety must stipulate the professional skills required by the enterprise. The requirements will be different depending on the type of potential sources of hazard present during the identification. For instance, identification of potential sources of hazard related to major accidents will require other skills than identification of potential sources of hazard related to other risks and health and safety risks not related to work.

8. Involvement of the safety organisation

Guidelines on how to involve the safety organisation or employees in risk management and in updating risk management are available in the DWEA guideline on cooperation on health and safety in connection with offshore oil and gas operations. The guideline does not imply that involvement is to take place in connection with design of new installations, but it does expect involvement in the design of major conversions of existing installations requiring a notification pursuant to section 27 of the Offshore Safety Act, and modifications to existing installations requiring a permit pursuant to section 29 of the Offshore Safety Act.