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LCA and the Working Environment

7 EDIP's process assessment method

7.1 The general methodology

Development of the EDIP method for assessment of the working environment was part of the Environmental Design of Industrial Product programme (the EDIP-programme). The programme was sponsored by the Danish EPA and the participators were five major Danish industrial companies as well as institutes at the Technical University of Denmark.

7.1.1 Purpose

The purpose of the EDIP project was (Wenzel, 1996)

• To develop methods for environmental assessment of complex industrial products,
• To develop guidelines for design and construction of environmentally friendly industrial pro.ducts,
• To develop a database and a computer based tool as support for environmental as.sess.ment, and
• To implement the methods and tools in the companies participating in the project.

7.1.2 The overall contents of the methodology

The purpose of the EDIP project was, as mentioned, to perform an environmental assessment of products. For this purpose a quantitative process assessment method for LCA was developed within the project. The assessment parameters used within the EDIP method are shown in Table 7.1. According to the table the method operates with three groups of assessment parameters: environmental effects, resource consumption, and working environmental effects.

Table 7.1. Assessment parameters used in EDIP.

Most of the effect potentials are relatively straightforward to handle in the quantitative assessment method. However, the quantitative assessment of the effect potentials "ecotoxicity" and "human toxicity" demands much more work. To avoid too much unnecessary work, screening methods have been developed. These screening methods can help in the decision of identifying the potential contributes to human toxicity or ecotoxicity. (Hauschild, 1996)

7.1.3 The general principles of the methodology

The EDIP methodology is based on the following steps:

• the data (e.g. resource consumption, emissions to air and water, waste etc.) from the product system are measured, calculated or estimated
• these data are classified by their potential to cause impacts, e.g. use of non-renewable resources, global warming and ozone depletion
• the data are characterised with respect to the impact categories, i.e. equivalence factors are used to determine the impacts from several sources to an impact category.

These steps follow the principles outlined in ISO 14040-series and are generally accepted as a sound methodology in LCA.

The aggregated impacts are subsequently normalised by relating them to the average annual impacts caused by one person in a relevant geographical area (the world/Denmark). In doing so, the contribution to an impact category is related to the potential impact from society's activities as a whole.

Finally, the impacts are weighted by use of international or Danish politically stated reduction targets for different impacts or specific compounds. Hereby it is assessed which of the potential impacts from a product system are most important.

These steps of the EDIP methodology differ slightly from the ISO 14040 standard, where only a weighting step is recommended. There is, however, little doubt that the normalisation step used in the EDIP methodology adds significant information, provided that the mechanism and principles are scientifically based and understood by the decision-makers.

7.1.3.1 Working environment

EDIP operates with three different methods for assessing the working environment, a screening method, a process assessment method, and a sector assessment method.

The screening method is a chemical screening method and thereby only covers the chemical working environment of an LCA. The chemical screening method can be used early in the product development or together with the process assessment method. In the last-mentioned case the chemical screening will be a preliminary step for the quantitative assessment with the purpose of deciding which processes to be included in the process assessment.

The process assessment method can be used in the assessment of the manufacturing process in the company and possibly for those subcontractors who are able and willing to supply the information needed.

The sector assessment method can be used together with the process method, in processes where specific working environmental data not are available

(Hauschild, 1996), (Broberg & Rasmussen, 1996).

7.1.4 Combined environment and work environment assessment

The assessment parameters used in the EDIP method are shown in Table 7.1. The method operates with three groups of assessment parameters (environmental effects, resource consumption, and working environmental effects), which all play an equal role in the methodology.

All three groups of assessment parameters are related to the same functional unit and measured by the same environmental unit - the person equivalent. Since the same basic assessment method is used, it is possible to aggregate over several steps in the life cycle and to compare the results from assessment of the working environment with other impact categories.

The data describing the working environment are collected from different sources depending on the assessment method used. For use of the chemical screening method, information about the chemicals used in the specific processes is needed. The screening gives the processes a score by relating them to European and national lists of dangerous substances and lists of substances with special effects.

The process assessment method requires more specific data from the company such as information concerning impacts due to accidents, chemicals, noise and monotonous repetitive work. Furthermore, it should be stated how much of the company's production time is used to manufacture the examined product in each of the processes.

When the sector assessment method is used, similar data should be collected. However, it should be noted that the data in this case represent the average working environmental impacts from the entire sector instead of the specific company and thereby will lead to higher uncertainty.

7.1.4.1 Software tool

The method describes that a software tool has been developed within the EDIP-programme. The software tool shows on which lists of effects (from the Danish Labour Inspectorate) a chemical or substance is registered and which classification EU requires. According to the method the program has not been updated. (Hauschild, 1996)

In the general EDIP software tool, room has been made for working environmental information, but the scattered information found there is far from sufficient to be a relevant help to perform a working environmental assessment. The software tool needs much development to be useful in the assessment of the working environment.

7.2 Working environmental assessment methodology

7.2.1 Purpose and goal

The purpose of the working environment project within EDIP was

• to develop a method for including working environmental parameters in LCAs based on the methodical framework described by SETAC and the EDIP programme,
• to use the developed method for assessing the working environmental impacts in the life cycle of five industrial products (reference products),
• to identify the critical working environmental impacts of the reference products and point out the possibilities of improvements of new products in progress,
• to outline the principles for good working environmental construction of industrial products, and
• to describe and evaluate the use of the developed methods and tools in product development within the companies participating in the project. (Broberg & Rasmussen, 1996)

The EDIP programme includes the working environment in LCAs for three reasons:

• the working environment should be included in LCAs to avoid working environmental deterioration when production processes are changed. LCAs will often be the basis of production changes or development of new products with lower environmental burdens. These changes determine the choice of production materials and processes, which directly influence the working environment.
• including assessments of the working environment in LCAs makes it possible to prevent working environmental problems when the LCAs are used in the technological planning.
• the working environment should be included in LCAs because some working environmental problems are of life cycle character, e.g. by chemical substances following the product throughout its entire life cycle.

The purpose of the process assessment method is to assess the working environment in the manufacturing processes within the company as well as the processes at the suppliers that are able and willing to supply the information needed. The method can be used in all phases of the product life cycle and it is suitable for assessing the whole product or just to compare single parts of selected products (Hauschild, 1996).

7.2.2 Scope of the methodology

7.2.2.1 System boundaries

As mentioned, all phases in the product life cycle can be covered by EDIP's process assessment method. The only exception is private use of the products. In this phase of the life cycle only impacts from activities indirectly related to private use of the products (e.g. production of electricity for use of the product) can be included in the method. This choice reflects the general structure of the Danish regulation. (Broberg & Rasmussen, 1996)

Allocation of the impacts from the working environment is normally done by the production time. The method prescribes that if there is no knowledge of the production time for the individual product, allocation of the impacts for the working environment can be done similarly to the allocation of the external environment. If, for instance, the energy flow is allocated by weight, the production time can also be allocated by weight. (Broberg & Rasmussen, 1996 and Hauschild, 1996)

7.2.2.2 Impact categories

Four impact categories and a total of seven effects are being assessed in EDIP's process assessment method, see Table 7.2. These impacts reflect the most common working environmental pro.blems in Denmark. The impacts are selected from the Danish Working Environment Service's overview of industries with serious working environmental problems. (Broberg & Rasmussen, 1996).

Table 7.2. Impact categories in the process assessment method.

The seven effects are selected from seriousness, knowledge of the interaction between exposure and potential effects together with data availability.

A more detailed specification of the impacts and effects related to the working environment is listed in Table 7.3.

The impacts have been selected from the Danish Labour Inspectorates' overview of working environmental problems in different industrial sectors in Denmark. The chosen impacts can be supplemented with other impacts in a further development of the methodology.

Table 7.3. Overview of impacts and effects related to the working environment

7.2.2.3 Data requirements

The authors of the method state that the process assessment method is best suited for assessment of internal production processes and for assessment of processes in supplier-companies from which it is possible to obtain knowledge of the exposures from the processes. If it is not possible to obtain knowledge of the processes in these companies, the authors of the method recommend that the assessment of these impacts is made by use of sector assessment or chemical screening. (Broberg & Rasmussen, 1996 and Hauschild, 1996).

Data requirements and sources as well as practitioners (exceeding "EDIP experts") are shown in Table 7.4. The table is divided into the same impact categories as shown in Table 7.2.

Table 7.4. Impact categories, data requirements and practitioners.

If possible, the exposure to the chemicals is assessed by use of working hygienic measurements. If measurements are not available the exposures are assessed on the basis of process parameters (open/closed process, ventilation/exhaustion, volatility, dust/aerosol formation, temperature etc.). The potential effects of the chemicals are stated on the basis of the Danish and European legislation. (Broberg & Rasmussen, 1996)

For accidents, calculations of the average risk of accidents by means of statistics and the production time are assumed to express how many accidents may be expected in the actual phase of the life cycle of the product. Since some occupational injuries are never reported these figures are probably underestimated. For larger companies, data and statistics specific for the company are preferred, but if these are not available, statistics for Denmark can be used.

7.2.2.4 Inventory parameters

The process assessment method includes the impact parameters shown in Table 7.5.

Not all the impact parameters shown in Table 7.5 are specified in the method, but are derived from the method description by the authors of this review.

Table 7.5. Overview of working environmental impact parameters included in the process assessment method.

The method states that the list of applied substances and materials for assessing chemical impacts will often be identical to the list of substances and materials for assessing the external environment. For noise, monotonous repetitive work and accidents, the data collection will be independent of the data collection for assessment of the external environment.

The fact that not all levels of exposure result in an effect is used to set impact thresholds within the four impact categories, see Table 7.6.

Table 7.6. Impact thresholds

The impacts are only included in the assessment if the impacts exceed the impact threshold. The time that the impact threshold is exceeded can subsequently be added to the exposure time for another process. The fact that the method only assesses whether or not the impact threshold value is exceeded (and not e.g. whether the noise level is 82 or 85 dB(A)) means that the level of exposure is not graded. A grading of the exposures would demand far more detailed data. (Broberg & Rasmussen, 1996)

The synergistic effects of chemical substances are not included in the process assessment method. When assessing the exposures the method assumes that no personal protective equipment (e.g. gloves) is being used. With this boundary it is assumed that the legislation is respected and prevention of working environmental problems instead of use of protective equipment is encouraged. (Broberg & Rasmussen, 1996)

7.2.2.5 Impact assessment

The process assessment method is not strictly in accordance with the ISO 14042 standard. The standard operates with five steps - category definition, classification, characterisation, normalisation (optional) and weighting (optional). EDIP's process assessment method operates with fewer steps.

In the EDIP process assessment method category definition and classification are carried out in one step, because of the fact that all effects are only related to one impact category (e.g. all incidents of allergy are classified under the impact category "allergy"). This is possible because the impact categories (Table 7.2) are very widely described in the method.

In the characterisation it is assumed that all exposures have the same effects if the impact thresholds (Table 7.6) are exceeded. This means that the method does not distinguish between the consequences of exposure to e.g. two different chemicals that are both carcinogenic.

The process assessment method also includes a normalisation step for each of the impacts where the impact has exceeded the impact threshold limit. The normalisation gives an idea of how relatively common the impact is and whether it is abnormally large. The reference value for the normalisation is time of impact per employee per year in Denmark. When the registered impact time is divided by the normalisation reference value, the impact is expressed as a unit person-equivalent. The unit person-equivalent corresponds to the impact that an average employee in Denmark is exposed to per year. (Broberg & Rasmussen, 1996)

The last step in the method is weighting where the number of potential work-related injuries for each effect is calculated. A weighting factor is calculated as the number of reported work-related injuries divided by the number of employees in Denmark. When the normalised data are multiplied by the weighting factor the number of expected reported work-related injuries per product is obtained. (Broberg & Rasmussen, 1996)

In the weighting step there is a risk that not all work-related injuries are reported which will lead to an underestimate of the number of expected reported work-related injuries per product.

When including the last two steps - normalisation and weighting - a number of uncertainties are introduces but at the same time these calculations add important information to the assessment. The normalisation and weighting steps are useful when comparing the potential effects from alternative products but the use is more doubtful when comparing different impact categories. In the description of the method it is emphasised that it will often be possible to make the working environmental assessment at an earlier stage and thereby preclude normalisation and weighting. (Broberg & Rasmussen, 1996)

7.3 Cases

One part of the EDIP project was a practical test of the developed methods. This was done by use of the method on different products. Each company participating in the project was asked to select a product for this purpose. In the following a short description of each case is given.

7.3.1 The refrigerator LER200 from Gram a|s

The examined product is a refrigerator LER200 (Low Energy Refrigerator). LER200 has the lowest energy consumption of the Gram refrigerators, and is among the refrigerators with the lowest energy consumption on the market. The functional unit is a volume of 200 litres cooled for 13 years to five degrees, with the temperature of the surroundings set at 25 degrees.

7.3.1.1 Collection of data

LER200 is made of several different raw materials from all over the world. Except for steel production, however, extraction of raw materials is not included in the working environmental assessment. The data used in the assessment of steel production are not from the specific supplier used by Gram, but are extrapolated data from another steel making plant.

Energy production is included by use of the sector assessment method. Both the process of extracting the materials for energy production and the energy production itself are included in the assessment. The data have been obtained from the countries supplying the Danish power plants with coal, oil and natural gas, and information from the power sector is used to account for the power production.

All production processes at Gram are included in the assessment, accounting for over 80% of the entire production phase. The rest of the production is situated at different suppliers, but it was not possible to obtain any working environmental data on these processes. Information on the working environment is apparently a more sensitive subject than information on the external environment, and other ways of collecting data must be established.

In the use phase, transportation of the finished refrigerator is included by use of the sector assessment method. An average of Danish transport of goods is used. Otherwise, only data concerning the production and use of energy are included. An average of the Danish power plants is used. No working environmental data could be found for the disposal phase.

7.3.1.2 Data processing

The working environmental profile shows that the total working environmental impact is lower than the environmental impact. LER200 has a long lifetime, and the only working environmental impact in the use phase is caused by the use of electricity. On the other hand the electricity consumption in the use phase is responsible for almost half of the total working environmental impact during the life cycle. Even though LER200 has one of the lowest consumptions of energy on the market, the use of electricity still plays an important part in the total working environmental profile.

The production phase is the most important phase with respect to the working environmental impacts. In the total picture, both transportation and steel production (steel represents more than 50% of LER200's weight) are insignificant processes.

The case study shows that it is possible to cover a large part of the products' life cycle. 75% of the life cycle is covered by a combination of the process and sector assessment methods. It may be difficult to find data for raw material acquisition and processing if these process steps take place in other countries. Despite the lacking data it was still possible to identify improvement opportunities on both the structural level and on the component level.

7.3.1.3 Company experience

A main experience at Gram A/S is that it is essential to use working environmental professionals in the data collection and that the data collection is anchored to one person in the company. Data collection from the suppliers to Gram A/S has proved to be very difficult. The product developers at the company have learned something about the working environment, and most of the results have been channelled to the safety organisation for future use. The company does not plan to formally integrate the working environment in product development. Instead, the company will involve the production technicians, who are main actors in working environmental issues, earlier in the process.

7.3.2 The JetpaQ pump from Grundfos a|s

The examined product is a JetpaQ pump used for water supply in private households. The JetpaQ pump was at an early stage of the product development when the EDIP case started, and it was therefor possible to include some of the results of the life cycle assessment in the product development.

The functional unit is supply of five cubic metres of water per hour with a pressure of 1.5 bar or a corresponding smaller amount of water with a higher pressure up to five bar for 4,870 hours.

7.3.2.1 Collection of data

The JetpaQ pump consists of stainless steel, plastics and tinplate which are delivered from all over Europe. For the production of raw materials average data from the EDIP database have been used. The only working environmental data available was for production of steel made from recycled materials. The JetpaQ pump was made from new materials but the production processes are assumed to be similar for new stainless steel and steel made from recycled materials. As steel covers 40% of the total consumption of materials in the pump, 40% of the production of materials is assessed.

The part of the production that is expected to take place at Grundfos - which is the major part - is included in the assessment. For noise impacts and impacts of monotonous repetitive work the total production time is considered as impact time. Furthermore the working environmental impacts from production of electricity are included in the assessment.

For use of the JetpaQ pump, the production of electricity at power stations as well as transportation by van are included in the working environmental assessment. No working environmental data for the disposal phase are included in the assessment.

7.3.2.2 Data processing

The largest impacts in the product life cycle are in the production phase and in the use phase. In the production phase the impacts are caused by energy production as well as the production at Grundfos and the impacts are monotonous repetitive work and noise. In the use phase the largest impact is noise due to production of electricity.

7.3.2.3 Company experience

The case shows that it requires much work to collect and assess the data. Since the product development was at a very early stage, it was difficult to predict where the components would be produced. Grundfos found that it was difficult to collect data from the suppliers. Grundfos sent a letter to a supplier, but there was no reply from the supplier.

The BST was essential in collecting the data and Grundfos expects that BST will play an important role in data collecting in the future. Furthermore the case showed that it was necessary to involve an expert in environment and working environment to handle the method.

The case also showed that it was difficult to identify possibilities of working environmental improvements in the life cycle of the specific product. The project leader expects that the working environmental improvements in the future will be on a company level and identified with help from the BST. It was also a conclusion that it was too complicated to use the work place assessments (APV) to collect the working environmental data.

7.3.3 The electrohydraulic activating unit (PVEH) from Danfoss a/s

The examined product is an electro-hydraulic activating unit PVEH (Proportional Valve Electric High performance) which is used in cranes and contractors' machinery. The product was selected for the assessment because of its complexity and because the company was developing a new generation of the unit. The functional unit is regulation of one hydraulic proportional valve in a hydraulic installation for five years.

7.3.3.1 Collection of data

In total about 80% of the working environment in the product life cycle is covered by the assessment. The production of electricity is included in all the phases and the transport of components and products is included in the assessment.

PVEH is made of materials and components from all over the world. For the production of raw materials only the production of steel is assessed. The product consists of 30% steel.

For the production phase, the production at Danfoss and the production of printed circuit boards at a supplier are included. The working time per component is calculated and all the processes are assessed. Noise and air pollution is measured at the working place and all processes have been evaluated for chemical impacts. Monotonous repetitive work has been assessed by BST and the risk of accidents has been extracted from the company's own statistics.

Extraction of crude oil for use of the activating unit is included in the working environmental assessment. The disposal phase is not included due to lack of data.

7.3.3.2 Data processing

The largest working environmental impacts are in the production phase which includes the production at Danfoss, the production at the supplier of printed circuit boards and the production of electricity to produce the unit.

As a part of the case study the working environmental consequences of a theoretic product change have been evaluated. The simulation showed that a change in the printed circuit board would minimise the working environmental effects by 12-100%.

7.3.3.3 Company experience

The BST at Danfoss has been involved in the data collection - especially concerning chemical products - and BST concludes that the method is directed towards experts.

The case shows that it is difficult to use the production time as a measurement for the working environmental impacts.

The life cycle assessment method and results of the working environmental assessment are not used in the product development process and the case study has not resulted in any changes of the working environment at Danfoss. Furthermore the case showed that it would not be possible to collect data for the EDIP method together with the data for the working place assessment (APV) (Broberg & Rasmussen, 1996).

7.3.4 The high-pressure cleaner Hobby 70 from KEW Industry

The examined product is a portable high-pressure cleaner "Hobby 70", which is a new product from KEW Industry. The functional unit used is cleaning of a surface for 125 hours over a five year-period for seven different types of cleaning. For every type of cleaning the use of electricity, water and chemicals is described.

Hobby 70 is made of more than 100 different parts. The main part of the components are produced in Denmark. Italy and the Netherlands are the most essential suppliers of materials. Less than 1% of the total weight of Hobby 70 is produced outside of Europe.

7.3.4.1 Collection of data

It was not possible to gather any information about the materials production, because no subcontractors gave this information. The processes production of raw materials and materials production are therefore not included in the assessment.

The production at KEW is mainly assembly work, but also some welding and grinding. The actual modelling of the product is carried out at subcontractors with processes like die casting, pressure die casting and chipping. No surface treatment is carried out. It was not possible to gather any information about the working environmental conditions at the subcontractors. Therefore only processes at KEW are included in the working environmental assessment for the production phase. By use of the sector assessment method, the working environmental impacts caused by the use of electricity are also included. An average of production of electricity from Danish power plants is used.

In the use phase water, electricity and detergents are needed. The use of detergents is included in the working environmental assessment, and by use of the sector assessment method, the working environmental impacts because of the use of electricity are also included.

Waste disposal and transportation is not included in the working environmental assessment because of lack of data.

7.3.4.2 Data processing

The assessment shows that the working environmental contribution is considerably smaller compared with the environmental contribution. However, only working environmental impacts connected to the use phase, electricity production and the production processes at KEW are included in the working environmental assessment.

The largest working environmental problem connected to Hobby 70 is accidents. Muscle-skeletal damage and hearing damage, which are mainly caused by the production at KEW, are also of high importance. 20% of the expected hearing damage is, however, caused by the production of electricity.

7.3.4.3 Company experience

None reported.

7.3.5 Beovision LX 5500 television from Bang & Olufsen

The Beovision LX 5500 television is a complex product. It consists of several different components made of different materials. Some production processes are carried out at Bang & Olufsen, and some at Danish subcontractors. However, a considerable part of the production processes is carried out at foreign subcontractors in mainly France and Germany.

It was not possible to gather information about the working environment from the foreign subcontractors. As the foreign subcontractors represent a considerable part of the life cycle of the television it was decided to leave out the working environmental assessment entirely of the LCA. This example therefore shows the importance of the geographical location of the companies, when it comes to collecting working environmental data for the LCA.

7.4 Discussion

In this section we discuss the strong and weak sides of the EDIP method. The text therefore reflects the opinion of the project group. The purpose of the discussion is partly to evaluate the method and partly to learn from the strong and weak sides of the method, and thereby be able to set guidelines for the "perfect" working environmental LCA.

In the discussion, the strong and weak sides of the method are firstly summarised (Table 7.7), after which the points are elaborated. Secondly, an overview of our evaluation of the working environmental LCA is given. Finally, suggestions for improving the method are discussed.

In a part of the discussion, EDIP's process assessment method is compared with another process assessment method called "IVF's process assessment method". The two process assessment methods are similar in some ways, but very different in others. IVF's process assessment method is described in details in the chapter 6.

Table 7.7. Strong and weak points of EDIP's process assessment method.

Some of the strong and weak points seem to be contrary. This only reflects the different experience from use of the method in the cases with different products and companies.

7.4.1 Methodical requirements

7.4.1.1 Integration with external environment assessment

The working environmental method can easily be integrated with the method for external environment assessment. The overall methodology is the same. This is regarded to be one of the major strong points. The working environmental method was developed to be integrated with the external environmental method. If working environmental LCA is going to be used on the same level as assessment of the external environment, the two parts should be integrated and based on the same units (person equivalent).

7.4.1.2 Normalisation and weighting

The method recommends that the assessment - if possible - should be made before normalisation and weighting. This shows that the authors of the method are aware that uncertainties are introduced when the normalisation and weighting steps are used. Especially when two different effects are compared, normalisation and weighting may underestimate the potential working environmental effects.

7.4.1.3 Comparison of products

The use of comparable data units makes it possible to distinguish between different products for the assessed effects. The availability of data on the same level of detail is however a necessity.

The method can be used for simulations of product changes. The available software tool can (anything being equal) be useful at this point.

7.4.1.4 Interaction with IVF's process assessment method

EDIP's method is in some ways similar to the IVF process assessment method. For instance IVF also uses the working time as an indicator of which processes can be excluded from the assessment without loss of significant information.

In both methods the normalisation is done according to the actual work-related injuries. As EDIP operates with the unit person equivalent and IVF operates with the economic aspect of the work-related injuries, the normalisation procedures cannot directly be transferred from one method to another.

To assess whether an impact leads to an effect or not EDIP uses impact thresholds. This means that there is no grading of the impacts. IVF uses a scoring system where the score can be negative or positive depending on the actual situation compared to the situation of "not having the examined job". For instance, a noise level of 95 dB(A) will give a higher score than 85 dB(A). The scoring system that operates with the actual exposure situation could be helpful in EDIP to provide a more graded and accurate picture of the impacts.

7.4.1.5 Importance of life cycle phases

The purpose of using a life cycle assessment in a product development course is to consider all the phases in the product life cycle. From the cases described, it looks like the method tends to weight the working environmental impacts during the production phase significantly higher than during the other phases. For instance during production of materials and during application, a large dilution of the impacts takes place because the impacts are measured per product (or per functional unit). This is a result of the method's use of allocating the impacts on the basis of the production time. If this dilution means that significant working environmental impacts are overlooked during one or more of the phases, fatal errors may be made during the product development. An example: A copy machine is developed so it has very little need for changing of spare parts, but it is accepted that some repairs will be ergonomically stressing to make. The method will dilute this impact because few repairs are carried out per measuring unit (the functional unit). The fact that the copier servicer performs this task daily and that his working environment in this way will be more stressed is ignored.

The method weights the impacts in proportion to the number of reported occupational damage. The reporting frequency of different types of occupational damage in Denmark is determined from whether the damage is acknowledged and listed on the occupational disease list.

This means that a very substantial number of actually occurring damage is not registered and as a consequence is not included in the weighting. To illustrate this may be mentioned various injuries to muscles and joints (for instance back injuries and PC mouse injuries), substances suspected of producing cancer and reproduction injuries.

From the cases it is an experience that it can be difficult to ascertain focus points for working environmental improvements in a specific product. It seems more obvious to improve the working environment at the company level in general.

There is no grading of the impacts in the method. Very large and significant differences in the working environmental impacts are not weighted. For instance, there is an enormous dif.ference between the noise impacts at 80 dB(A) and 95 dB(A). When it is considered that the noise limit has only recently been lowered from 90 dB(A) to 85 dB(A), almost all life cycle assessments will register a relatively high noise impact for some time to come.

The use of the production time as a measure for the impact will in many cases give an unwanted dilution effect. See also above: "The method tends to weight the impact during the production phase higher...".

7.4.2 Working environmental aspects

A strong point of the method is that it includes other working environmental impacts than the chemical and that it assesses other effects than the toxic.

A weak point of the method is that it by its inherent limitations precludes some very significant working environmental impacts and effects. If the method is used in a product developing course, an assessment should be made in advance of whether the method will be reasonably covering for the product in question. The method gives no guidelines as how to make such an assessment. In a number of production processes an unbalanced impression may result from the selection of working environmental parameters and effects, as for instance, impacts such as vibrations. In all processes where hand-held tools are used, the vibration impact in the form of hand/arm vibrations will be significant - often a larger impact than noise.

Another example is dust (particles). In all processes involving material finishing (cutting, chopping, sharpening, boring, welding, etc.), in processes using or handling powdered materials, in processes where high-pressure coating takes place and in a number of other pro.cesses, a major dust impact on the working environment exists. Some of the harmful effects of the dust will be covered by the chemical screening but the physical impact on the organism will not be included in the assessment. This means that the risk of respiratory damage and the resulting consequences for cardiovascular diseases will not be assessed.

Finally, it seems a drastic limitation of the ergonomic impacts that the analysis is limited to monotonous repetitive work. Firstly, monotonous repetitive work is generally only seen in the production phase. In this way it will only be during one of the life cycle phases that the ergonomic impact is included. If the method had chosen to use, for instance, the definition for heavy lifting, ergonomics had been included in all the life cycle phases. Secondly, the extent of lifting work and working postures has a very major influence on the working environmental impacts in general (the occurrence of back and knee injuries, etc.).

A weak point of the method is that essential long term effects by a chemical impact of the working environment may be overlooked when the impacts are assessed.

For the chemical impacts the method has determined a limit of 10% of the threshold limit value, calculated as a sum of fractions. The Danish threshold limit values (TLV) have not been fixed on an unambiguously equal basis. Historically, only the acute effects of the substances form the basis of determining the value. For a number of substances the values have later been significantly lowered due to the substances' long time effects. One example is Styrene, where the threshold limit value some years ago was lowered by a factor 100 after an incident at Sønderborg Skibsværft.

7.4.3 Practicability

The cases have shown that the method can be used in pointing out directions for improvements. This is a strong point in the general production development schedule in a company.

Usefulness and practicability of LCA methods depend primarily on the purpose of the assessment and on the users' background and experience. Table 7.8 contains an evaluation of the practicability of the EDIP's process assessment method for different applications.

Table 7.8. Practicability of EDIP's process assessment method.

The table is divided into six applications that reflect the different levels where the method is expected to be used. The usefulness and practicability of the method are estimated based on the method description and the experience from the cases.

As shown in the table the method is best suited for use in companies with LCA expertise and an environmental department. For (smaller) companies without LCA expertise and very specific products the method is too complicated.

The method is technically complicated and demands a scientific background, especially general knowledge about LCA.

7.4.3.1 Complicated software tool

The software tool is to complicated to use for designers and constructors. This is a general problem as the tool needs a good and easily understandable surface. However, it is also a specific problem regarding the working environmental assessment that the tool only contains very few useful data.

7.4.4 Data issues

The BST system is well integrated into the working environment activities in many companies. The possibility of using data from BSTs will be a help in obtaining the necessary data.

A strong point of the method is that it includes other data than the available statistics. Especially, it offers the possibility of including data from observations and measurements on the work places.

In the cases this point is regarded as the most difficult for the general user. As the method is now (together with the available software tool), it is difficult to carry out a complete process assessment without the assistance from an LCA expert with a background in chemistry.

Working environmental conditions at the suppliers are regarded to be an important part of any assessment. At present it is, however, in general difficult to obtain the necessary detailed data. Future focus on working environmental data in companies (e.g. by law regulations and work place assessments) could possibly improve this situation.

The problem of involving the safety organisation in the data collection is related to the complexity of the method. In general employees in a safety organisation do not have the necessary LCA knowledge to perform this work.

7.4.5 Summary of the assessment

In Table 7.9 the above discussion is summarised. The table illustrates how the project group evaluate EDIP's process assessment method. The exact meaning of the topics in the first column are described in section 1.10.

Table 7.9. Fulfilment of general LCA requirements.

Topic	EDIP's process assessment method
Methodical requirements
Integration with LCA for external environment
Applicability in LC-phases
Aggregation possible
Working environmental aspects
Coverage of WE'al issues
Graduation of exposures and effects
Practicability
Practical in use
Software tool
Transparency
Can be used by non-experts
Data issues
Data reliability
Amount of data in existing database
Data accessibility
Data can be obtained by WPA

= missing, = poor, = acceptable, = good, = excellent

7.4.6 Suggestions for improvements

The use of "hazard concept" instead of impact threshold limits when choosing system boundaries and selecting impacts parameters should be considered.

A grading of the impacts should be considered. For instance, after the same principles as when results of working hygienic measurements are assessed over a total work week or as the scoring system in IVF's process assessment method.

To improve the collection of relevant data it should be analysed how the working place assessments can be used in the data collection.

Normalisation and weighting add uncertainty to the method. It should be considered either to preclude weighting and normalisation or alternatively to consider whether more accurate data material could be made available.

It should be considered to make the method more open towards working environmental impacts and effects and then choose system boundaries and select impact parameters later in the assessment.

7.5 References

Broberg O., Rasmussen E (1996). Forskningsrapport Arbejdsmiljø fra vugge til grav. English title: Working environment from cradle to grave. Arbejdsmiljøfondet, Copenhagen.

Wenzel H, Hauschild M, Rasmussen E (1996). Miljøvurdering af produkter, UMIP. English title: Development of environmental friendly industrial products - Environmental assessment of products. IPU/DTU, Miljø- og Energiministeriet - Miljøstyrelsen, Dansk Industri.

Hauschild M (ed) 1996. Baggrund for miljøvurdering af produkter. IPU - DTU, Miljø- og Energiministeriet - Miljøstyrelsen, Dansk Inudstri. English version: Environmental Assessment of Products. Volume 2: Scientific background. Chapman & Hall, 1997.

ISO (1998). ISO 14042 Environmental management - Life cycle assessment - Life cycle Impact assessment. Committee draft (ISO/CD 14042.22), 28.1.1999

Footnotes

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Version 1.0 April 2004, © Danish Environmental Protection Agency