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LCA and the Working Environment

4 IVL's sector assessment method

4.1 The general methodology

IVL, the Swedish Environmental Research Institute (Institutet för Vatten- och Luftvårdsforskning), has developed a method for assessment of the working environment. The development of IVL's sector assessment method was sponsored by the Swedish Work Environment Fund. The method only covers assessment of the working environment and does not refer to any specific method for assessing the external environment.

As the method is based on statistics, it primarily deals with effects rather than exposures. This makes it difficult to describe the method according to the framework used in this project.

4.1.1 Purpose

The purpose of including the sector assessment method in LCA is to ensure that environmental improvements do not result in deterioration of the working environment (Antonsson, 1995a).

The method was developed with the purpose of integration in the quantitative LCA methods that are developed within the framework of SETAC and in projects financed by the Nordic Council of Ministers (Antonsson, 1995b).

4.1.2 The overall content of the methodology

As IVL's sector assessment method is not connected to any certain method for assessment of the external environment, there is no prescription of such a method.

4.1.3 The general principles of the methodology

The method recommends use of the principles outlined in the ISO 14040-series (Goal and scope definition, Inventory analysis and Impact assessment), but it does not strictly follow the principles.

The working environment method is based on official statistics for different sectors or individual companies. The result is a number of expected accidents and diseases related to the production of e.g. one ton of steel or to a service.

The method is based on five quantitative and two semi-quantitative effect categories. The quantitative effect categories do not include exposure but only effects, whereas the semi-quantitative effect categories includes both exposure and effects:

Quantitative effect categories

• death due to work-related accidents
• workdays lost due to work-related accidents and diseases
• workdays lost due to illness (exceeding normal)
• hearing damage
• allergy, eczema and similar diseases

Semi-quantitative effect categories

• cancer
• prenatal damage

4.1.3.1 Combined environment and work environment assessment

As mentioned, the method can be used in combination with earlier developed quantitative methods for life cycle assessment of the external environment. The method does not recommend any specific method.

4.1.3.2 Software tool

No software tool is available.

4.2 Working environmental assessment methodology

4.2.1 Purpose and goal

First of all, it was a demand for IVL that the method should be quantitative. Secondly - as mentioned – it should be suitable for integration in the quantitative methods that have already been developed to assess the external environment (Antonsson, 1995a).

In addition to this, the method should include all aspects of the working environment and it should be able to cover the variable working environmental aspects in the life cycle of different products and services.

4.2.2 Scope of the methodology

4.2.2.1 System boundaries

In principle all phases in the product life cycle (including transportation, energy consumption?, etc.) can be covered by IVL's sector assessment method. The method can be performed on a sector or at company level.

For the semi-quantitative categories only effects caused by impact from the main production line are included in the assessments. Repairs, office functions etc. are not included.

The work-related effects are allocated to the product by the economic value of the production (e.g. for goods transported by train, allocation is made by the percentage of the total income for the railway, that is related to transportation of goods).

4.2.2.2 Impact categories

The seven effect categories (five quantitative and two semi-quantitative) are shown in section 4.1.3. In principle all impacts that leads to any of the effects in the effect categories are included in the method. In the effect category "workdays lost due to work-related accidents and diseases" several impacts, e.g. chemical, ergonomic, psychosocial and physical are included.

The category "workdays lost due to illness (exceeding normal)" does in principle cover other work-related effects, e.g. psychosocial effects (or effects that are due to factors in the work environment, but which are rarely reported). It is, however, not clearly defined in the method (Antonsson, 1995a), which environmental factors this impact category encompass.

In general the effect categories have been chosen to reflect the most serious working environmental damages. In addition to this the quantitative effect categories have been selected on the basis of

• availability of statistical data
• clear correlation between the exposure to the working environment and the effects
• an aim to reduce the number of categories in order to make the method as simple as possible

The semi-quantitative effect categories have been included due to their consequence and seriousness.

4.2.2.3 Data requirements

Data for assessment of the quantitative effects are collected from official statistics on a sector or company level. It is mentioned in the description that it can be difficult to ensure that the sectors are defined similarly in different data sources. For large companies it is recommended using data on company level instead of sector statistics.

To improve the quality of the data, it is recommended that – whenever possible - the average values from a period of several years (approximately five years) should be used. It is also recommended that standard deviations should be calculated for use in a sensitivity analysis (Antonsson, 1995b).

Table 4.1. Data requirement and sources for IVL's method.

Statistical data for the quantitative effect categories are primarily collected from ISA (Occupational Injury Information System) at the Swedish National Board of Occupational Health. All Swedish work-related accidents and diseases resulting in absence from work are reported to ISA. Data on average sick leave are provided from the Swedish Social Insurance Office.

For each sector the yearly production amount is calculated from SCB (Statistiska Centralbyrån - Statistics Sweden). The number of incidents in each effect category is divided by the yearly production amount. If the sector produces more than one product, the effects are allocated by the economic value of the products.

The data are aggregated over the phases in the life cycle.

The result of the life cycle assessment is one figure for each of the effect categories showing the expected work-related accidents/diseases from the product life cycle.

4.2.2.4 Inventory parameters

The method does not deal with exposure in the same way as e.g. EDIP's process assessment method. For the five quantitative effects the method only deals with the accidents and diseases that are registered in the sector and company statistics.

For the two semi-quantitative effects it is evaluated whether the impact threshold limit values are exceeded or not. For a further description, see the next section.

4.2.2.5 Impact assessment

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

As mentioned, the method does not operate with exposures but only statistics of effects (except for the semi-quantitative effects). When the effect categories are defined, classification is carried out for cancer and prenatal damage. The classification is simple as e.g. exposure of substances causing cancer is related to the effect category "cancer".

In the assessment of semi-quantitative effect categories the exposures which may cause cancer and prenatal damage are examined. As mentioned only effects caused by impact from the main production line are included in the assessments.

The semi-quantitative effects are characterised in four categories:

1: Unacceptable effects
2: Unwanted effects
3: Other effects
4: Substances under suspicion but the effects are not documented

Cancer. The characterisation is done in accordance with present legislation (Impact threshold limits, prohibitions etc.). It is recommended that an effect should be characterised as category 1 when 50% of the threshold limit value is exceeded or if proven carcinogenic and prohibited substances are being used. Category 2 is used when there is adequate knowledge that the substances are carcinogenic and when handling of the substances implies exposure. If the exposure is very controlled, category 3 applies. Substances under suspicion of being carcinogenic are characterised as category 4. (IVL, 1995 p. 21-22)

Prenatal damage. When regarding the risk of prenatal damage it is a problem that it is uncertain whether pregnant women are exposed or not. The characterisation is done on the basis of existing legislation (legislation applying to all women but not to men). Category 1 is used when general rules and regulations concerning substances with reproductive impact are not respected. Other substances with reproductive impact are characterised as category 2 or 3 dependent on the exposure. If the relation between the substance and the risk of prenatal damage is uncertain, category 4 is used.

4.2.2.6 Weighting and normalisation

Weighting and normalisation is not used in the method. An option proposed by IVL (personal communication) is to introduce normalisation by comparing the statistics per person for four of the effect categories (excluding workdays lost, exceeding normal) with the average numbers for the effect categories. The average numbers could even be subtracted from the actual numbers before counting the contribution from the different sectors to the total life cycle impact on the working environment.

4.3 Cases

4.3.1 Energy production, transportation and steel production

In order to evaluate the method, IVL has performed an assessment of:

• energy production (production of 1 GWh of electric energy and district heating)
• transportation of goods (million ton-kilometres by train, truck or aeroplane)
• steel production (manufacturing of 1 ton of steel).

These activities were chosen because they will occur in most life cycle assessments.

4.3.1.1 Collection of data and data processing

The data are based on statistics for sectors and not all the life cycle phases are included (e.g. the production of raw material is not included in the assessment of energy production). The statistics are based on data from ISA and SCB and have been standardized according to age and sex.

In all cases the category "workdays lost (exceeding normal)" as well as the semi-quantitative effects are not included. The results concerning the quantitative effects are stated as mean values with a standard deviation for the period 1987 to 1991.

No company experiences are described, but as a conclusion of the cases it is stated in the method description that further testing and development will be necessary before the method is ready for regular use in life cycle assessments.

At present IVL is testing the method in a case study, a comparison of different ways to treat grinding swarf from grinding of steel. Another case study is planned which will focus on two alternative fuels that are different with respect to most of the sectors that are part of the life cycle. The testing is documented in Antonsson (1999). The method will be adjusted in the testing, but the basic statistical concept will not be changed.

4.4 Discussion

In this section we discuss the strong and weak sides of IVL's 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 form the strong and weak sides of the method, and thereby be able to set guidelines for the "perfect" working environmental LCA.

Firstly the strong and weak sides of the method are summarised in the discussion (Table 4.2) where after 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.

Table 4.2. Strong and weak points of IVL's sector assessment method.

4.4.1 Methodical requirements

4.4.1.1 Supplement to any LCA method

The IVL sector assessment method is not related to any specific LCA method for assessment of the external environment. In principle the sector assessment method can be used as a supplement to any LCA method.

4.4.1.2 Requires only a limited number of data

The methodology is simple and as it is based on statistical data on a sector or company level. It does not require measurements or observations at the working place. This makes the method quick and inexpensive to perform.

4.4.1.3 Aggregation is simple

As the result of the method is a number of expected incidents, the aggregation of the life cycle phases is very simple. The method is suitable to compare alternative products and services, but it might be difficult to identify the critical situations in the life cycle phases.

4.4.1.4 Difficult to cover all phases in the life cycle equally well

As the statistical data can vary a lot for the different phases it will be very difficult to cover the entire life cycle with data of high quality. Especially the production of raw materials can be difficult to cover because the materials often are produced far from northern Europe where the working environmental registration is completely different.

It is difficult to relate the result of the sector assessment to a specific product or process, as the statistical data covers a large number of different companies and processes. In the cases the work-related effects are allocated to the product by the economic value of the production.

4.4.2 Working environmental aspects

The method recommends company statistics from large companies on "workdays lost due to illness" (exceeding normal). It is, however, not stated how large the companies should be. Furthermore, it is not quite clear which working environmental factors are included in this impact category. Due to the uncertainty of what exactly is included, and the lack of this form of statistical data in Denmark, it is questionable whether the category is usable in Denmark, or in other countries.

4.4.2.1 Number of accidents and diseases can be underestimated

The method is based on statistics of reported accidents and occupational diseases. A weakness of this procedure is that the actual number of work-related accidents can be underestimated, because not every actual work-related accident will be reported.

4.4.2.2 Includes both chemical and non-chemical effects

An advantage of the method is that both chemical and non-chemical effects are included. The method calculates the number of accidents, hearing damages, and several chemical effects. It is, however, opaque which working environmental factors are responsible for a higher rate of workdays lost - exceeding normal.

4.4.3 Practicability

4.4.3.1 Lack of data

If the method is completed with unreliable data or the data are not measured or calculated in the same way - e.g. data from different countries - the result of the assessment can be unreliable. Use of unreliable data is, however, not a weakness of the IVL method in itself, but a weakness of this type of LCA method in general.

4.4.4 Data issues

4.4.4.1 Low number of reported incidents in some sectors

The statistical data on hearing losses and allergies, eczemas and similar diseases will consist of very low numbers from companies or trades. The limited number of statistic data will make the results unreliable. However, IVL tries to handle this uncertainty by calculating the mean value and standard deviation over a five years period.

The method is only based on statistical data and it is very dependent on the access to data of a satisfactory quality. The method is based on statistics from Sweden and it is questioned whether all data and statistics described in the method will be available outside Sweden.

4.4.5 Summary of the assessment

In Table 4.3 the above discussion is summarised. The table illustrates how the project group evaluates the IVL method. The exact meaning of the topics in the first column is described in section 1.10.

Table 4.3. Evaluation of the IVL method.

Topic	Evaluation of the IVL 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

4.4.6 Suggestions for improvements

On basis of IVL's ongoing testing, the method will be further developed. To ensure success of the method outside Sweden, it is very important to consider how the method is best suited for the varying statistics from different countries.

At the moment, no software tool is available. The method is, however, based on statistical data, which can make it easier to create a database.

4.5 References

Antonsson A-B, Carlson H (1995a). En metod för att integrere arbetsmiljö i livscykelanalyser. English title: A method for integrating working environment in life cycle assessments. , IVL Instituttet för vatten- och luftvårdsforskning.

Antonsson A_B, Carlson H (1995b). The basis for a method to integrate work environment in life cycle assessment. J. Cleaner Production, Volume 3(4): 215 – 220.

Antonsson A-B, Nilsson M (1999). Arbetsmiljö-LCA – viderautveckling av en kvantitativ metod. IVL-rapport B 1320. IVL, Stockholm.

ISO (1997). ISO 14040: Environmental management - Life cycle assessment - Principles and framework. First edition, 15.06.1997

ISO (1998). ISO 14042 Environmental management - Life cycle assessment - Life cycle Impact assessment. Committee draft (ISO/CD 14042.22), 28.01.1998.

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Version 1.0 April 2004, © Danish Environmental Protection Agency