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Sailboats and motorboats in varying colors moored at the harbor on an overcast day.

Advice and recommendations

Undersökningar av fartygs innemiljö visar att luftkvaliteten till största del är god men att det finns utrymme för förbättringar. Även om luftkvaliteten inte utgör någon hälsorisk, har den betydelse för hur innemiljön upplevs och för besättningens arbetsprestation. I det här avsnittet lämnar vi förslag på tekniska och organisatoriska åtgärder som kan vidtas för att ytterligare förbättra fartygens innemiljö, arbets- och boendemiljö.

Both Swedish and international OEL values for hazardous substances are based on the scientific basis of known dose-response effects, i.e. how much of a substance people can be exposed to without suffering acute or long-term health effects. OEL values are also set taking into account economic and social impacts and what is technically and practically feasible. It is therefore not possible to say with certainty that air pollutants are completely harmless if they are present at levels below the limit value.

For some of the air pollutants studied, such as benzene and PAHs, the WHO states that no safe levels can be recommended (WHO, 2010). In practice, this means that risks from exposure to hazardous air pollutants should be managed according to the principles of the prevention hierarchy of control, where risks should be eliminated or minimised as far as is economically and technically feasible.

Air quality on ships is important both for the perception of the indoor environment and for the work performance of the crew. The concentrations of various substances in the indoor environment are largely influenced by the type of ship and the type of fuel used. Type of ship and fuel are decisions that are made at a strategic operational level and the crew has little or no control over these decisions. However, with a well thought-out design of the ship's technical equipment and ventilation system, it is possible to reduce the levels of hazardous air pollutants even on tankers and in engine rooms, where the levels are generally the highest.

The duties performed also have a significant impact on the exposure of seafarers to air pollutants. Although service personnel are generally less exposed, they may also have tasks and working conditions that need to be investigated. It is therefore important to identify working situations on board that may give rise to an increased risk of illness and accidents for all categories of pers

Suggested measures for existing ships

This section provides examples of investigations and measures that can be carried out to improve the indoor environment on existing ships. Based on the hierarchy of control, measures should first and foremost eliminate and minimise risks. This may involve technical measures, such as reviewing general ventilation and local exhaust ventilation, or investigating the feasibility of introducing closed processes to reduce exposure. It may also involve organisational measures, such as reviewing how work is organised to see if risks can be reduced by, for example, limiting the time the worker is exposed to the risk or introducing job rotation. The use of personal protective equipment should always be the last step.

Inspection and maintenance of ventilation systems

A ship will normally have several ventilation systems on board. Effective procedures must be in place for regular inspection and cleaning of the systems to ensure that air pollutants are effectively removed and that all spaces have adequate air circulation. This applies to general ventilation systems as well as process ventilation and local exhaust ventilation in workshops, paint shops, galleys, etc.

Staff must also have access to written instructions that clearly explain how each system works, how to service and maintain it safely, and how to troubleshoot it.

To reduce the spread of dust and harmful substances, hand tools such as welding torches, grinders and cutting machines can be fitted with built-in extractors that effectively capture airborne pollutants. Integrated extractors capture pollutants close to the source before they can spread throughout the workplace.

Order and tidiness

In general, it is important to maintain order and hygiene in both working and living areas. Shipboard work means that many people are present in a relatively small area. Previous research has shown that there is an increased risk of infectious diseases spreading. Poor ventilation, lack of maintenance of ventilation systems, inadequate cleaning or incorrect cleaning methods can increase the risk of health problems. Good cleaning practices keep particle levels low because dust acts as a reservoir for particles, from which new particles are constantly generated. Effective procedures for cleaning premises and equipment also make it easier for cleaning staff to do a good job.

Tidiness is facilitated by a clear understanding of the location of equipment, tools, materials, etc. and that 'there is a place for everything'. In workplaces where there is frequent turnover of staff, it is important that these procedures are clear so that they can be applied by everyone, including those who are in the workplace only temporarily.

In office environments, for example, it is advisable to keep computer and other equipment cords in special channels or bound with cable ties, and to keep table surfaces clean so that they can be wiped down and kept clean.

The highest levels of contaminants have been found in ships' engine rooms, particularly in the separator room. It is therefore important to have procedures in place to minimise exposure to vapours from the ship's fuel and lubricating oils. Tank tops and spillways must be regularly cleaned and leaks sealed. Even small leaks from valve stems, pump shaft seals and the like should be dealt with as soon as they are discovered. Although these are areas where personnel are not intended to be present during working hours, it is still the case that machinery personnel spend many hours in these spaces, for example, cleaning and maintaining filters, fuel and lube oil separators and other equipment. Instead, the actual cleaning work should be carried out in dedicated cleaning rooms, where it is possible to transport the items to be cleaned. Large vats of diesel oil should not be used for cleaning. Where possible, other less hazardous cleaning agents and methods should be used, such as ultrasonic cleaning or clean-in-place (CIP), which do not require major dismantling.

Personal protective equipment

Based on the hierarchy of control, the use of personal protective equipment is always the last step when it is not possible to eliminate or further reduce the risks by other technical or organisational measures. All personal protective equipment should be selected and designed to suit the wearer and be appropriate to the work being carried out.

Where respiratory protective equipment must be used, it should be specifically designed to ensure that the size and model of the equipment is appropriate for the person using it. The same respirator will not fit all faces. Respirators designed to fit tightly against the face, known as tight-fitting respirators, must also be tested for tightness. This can be done by a fit testing using an appropriate quantitative or qualitative method. Quantitative methods are based on either measuring the number of particles inside and outside the respirator or measuring the air pressure inside the respirator. The qualitative method basically involves wearing the respirator under a hood covering the head, neck and shoulders. A flavour or fragrance is then injected into the hood. If the user can taste or smell the substance, the respirator does not seal properly. The test should be performed by a person with knowledge of respirator use and fit testing methods.

More detailed descriptions of fit testing methods are given in the international standard ISO 16975-3:2022.

Proposed measures for new buildings

At the design stage, it is important to consider the design of ships and the choice of equipment. Of particular importance for the indoor environment are:

  • the choice of propulsion system and fuel
  • ventilation arrangements
  • the design of workplaces and engine rooms, where the highest levels of air pollution have been measured.

Propulsion and fuel

Air quality on board is strongly influenced by the fuel used for propulsion and auxiliary engines. In addition to the improvements in air quality that have been demonstrated by using cleaner fuels, there are other improvements in the working environment. For example, maintenance and cleaning intervals for filters and separators can be extended, and the work itself can often be done in less time because cleaning is much easier. Ships running on heavy fuel oil require more time and the use of more and stronger chemicals to clean tanks, sump trays and other equipment.

All operational options have characteristics and risks that require special consideration in the design of systems, operation and maintenance procedures, training and emergency procedures. Risk assessments must therefore cover the risks of serious injury and ill health as well as the satisfactory performance of tasks.

All liquid fuels are considered toxic, with the exception of natural gas. Methanol is acutely toxic by both ingestion and dermal exposure. However, it is not carcinogenic. As ships still have systems to run on petroleum-based fuels, few tasks have disappeared completely and none of the operational alternatives involve lower direct costs for personnel. However, there are differences in how often different tasks need to be performed and under what conditions. Cleaner fuels reduce the need to clean components and machine areas. This in turn means less exposure to hazardous substances and that working time can be spent on other tasks that are perceived to add value. Since many jobs on board involve simultaneous exposure to several known risk factors, a holistic approach is needed that includes preventive measures and long-term health promotion. It is not enough to target only the worst exposures.

Each operational option has its own characteristics and risks. These require special consideration in system design, operation and maintenance procedures, education and training, and emergency procedures. Whichever option is considered, it is essential that health and safety aspects are considered as early as possible in the planning and design process. These do not only have to cover risks of serious injury, but also ensure that work tasks can be carried out in a satisfactory manner throughout the life of the ship, with the minimum risk of ill health and accidents. This requires a systematic analysis of working environments and tasks during operation, maintenance and emergency situations.

To a large extent, the work of the engine crew is affected by the choice of propulsion system and fuel. This is primarily related to tasks that affect the ship's fuel system and propulsion in various ways, but also work with other peripheral equipment such as bilge water and sludge handling, and not least general cleaning of the engine rooms.

Ventilation arrangements

There are special requirements for ventilation arrangements, such as the location of vents on certain tanks in relation to fresh air intakes. On Swedish ships, there are also requirements for special process ventilation in workshops, galleys and paint stores where paint is mixed. Even for those tanks where there are no special requirements, the location of vents and their relationship to air intakes should be carefully considered. It is also important to ensure that engine exhaust is directed away from the ship in such a way that there is no risk of it being drawn into the fresh air intakes, regardless of wind conditions or direction.

Design of workplaces and living environments

From the design stage, it is important to ensure that all common tasks can be carried out safely and efficiently.

Premises and living areas need to be designed and dimensioned for normal cleaning. For example, there must be sufficient space to manoeuvre a cleaning trolley, vacuum cleaner and other necessary equipment. Access to and location of scuppers and other drains must also be planned. Clear floor surfaces make cleaning easier. In toilet and shower areas, cleaning is facilitated if the toilet seat and washbasin are wall-mounted.

Engine rooms must have a dedicated cleaning area where filters, separators and other machine parts can be lifted for cleaning. This can be achieved either by means of lifting beams running through the engine room and directly into the cleaning room, or by allowing the parts to be moved there by trolleys or pallet jacks.

Cleaning rooms should be well ventilated. Excess air should be exhausted and should not enter adjacent machinery and personnel areas. The cleaning room should also have access to hot and cold water, compressed air and high-pressure washing facilities.

In addition, work should be organised in time and space to avoid unnecessary strain on the respiratory system. Increased physical exertion increases breathing and the absorption of contaminants. Engine rooms in general and separator rooms in particular are often hot. Even the ship's galley can sometimes have high temperatures, depending on the climate zone. Working in intense heat increases stress on the body, so it may be necessary to plan regular breaks in cooler and better ventilated areas. This booklet focuses on uptake through the respiratory tract, but absorption of harmful substances also occurs through the skin. It is therefore important to ensure that procedures are in place for changing and cleaning work clothing and gloves, and that appropriate protective gloves of the right type and size are available.

Although the concentrations of airborne contaminants measured are well below the OEL values for catering staff, it is still important to design ship galleys to provide good general ventilation throughout the space, supplemented by special extractors at frying tables and the like to capture airborne contaminants close to the source. As with other spaces, it is important to have good procedures for cleaning and maintaining work equipment and ventilation systems. Work also needs to be organised to reduce individual exposure through job rotation, job changes and the opportunity to take breaks in a lower-exposure area.

On cargo ships, the cook has little opportunity to rotate with another person on board, but instead has a natural rotation of work as they do all the kitchen tasks themselves. Fewer portions are prepared than on a passenger ship. On cargo ships, cooks are more exposed to fuels and their exposure is characterised by personal habits such as the use of perfume, shaving cream or chewing gum.

Measures to reduce exposure can be both technical and organisational. It is important to provide good general ventilation for both workstations and cabins. In some areas, such as welding and machining workstations, cleaning of engine parts, mixing of paints, over frying tables in the kitchen, etc., it may be necessary to supplement the general ventilation with special or improved exhaust systems to capture air pollutants close to the source. Good cleaning and maintenance procedures for work equipment and ventilation systems are also important. Organisational measures can include planning and distributing work to reduce individual exposure through job rotation, job changes and opportunities for breaks in lower-exposure areas.

Thinking ahead about changes that affect the work environment

The Work Environment Act places great emphasis on the importance of planning for a good work environment. In Swedish workplaces, it is a legal requirement that changes to operations that may affect the work environment must be risk assessed. The risk assessment must be carried out together with the work environment representative and the personnel affected by the change. This also applies to Swedish-flagged vessels. For ships that are not covered by Swedish work environment legislation, this type of risk assessment can be carried out because it is a good idea, even though it is not an explicit legal requirement. The idea is to identify risks so that they can be addressed while it is still possible.

Deficiencies in the design of workplaces and systems can lead to failure of the person performing the task:

  • Spend too much time doing the job, resulting in less time for other tasks.
  • Do the job incorrectly, which can lead to harm to people, equipment and the environment.
  • Become stressed and insecure, reducing their ability to complete tasks.
  • Do not know how to use the different functions of the systems, which means that the benefits are not realised.

Well-designed workplaces and systems, on the other hand, enable the tasks to be performed safely and efficiently, reduce the learning time required to perform the task, and increase the commitment and satisfaction of those performing the task. Ultimately, it also leads to lower development costs.

The earlier you start developing new workstations, the greater the opportunity to make changes. At the same time, the cost of these changes is low. The ability to influence and change flaws in the design of a system decreases over time, while the cost of change increases.