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Manual on Product-Oriented Environmental Work

1 Overview of a product's life cycle

This tool can be used to obtain an overview of a product's life cycle. It is the first step in a real environmental assessment.

When you use this tool, the main results you obtain are:

	an overview of the phases of the product's life cycle
	clear definition of the scope of a life cycle review
	collection and organisation of data in a suitable form.

The tool consists of five steps:

1. Designation of the product
2. Preparation of list of materials and substances
3. Preparation of flow diagrams/process tree
4. Quantification of input/output flows
5. Completion of MECO form (MECO = Materials, Energy, Chemicals and Other).

In general, with this tool, you must use as your basis the data that are easily accessible.The work involved in using the tool takes 1-2 weeks.We recommend that you obtain "Manual on Environmental Assessment of Products" (see the reference list), which will help you carry out a real environmental assessment of the product.

1.1 Designation of the product

Before you start it is important to designate the product you are going to work on.

Think about the following questions:

	Are there two products you want to compare to clarify whether the environmental impact is smaller for one than for the other?
	Do you want to determine whether a modification of a product will reduce the environmental impact?
	Do you want to look at a product to see where the significant environmental impacts occur in its life cycle?

It is important to define what the product or products you choose to work on does/do. This is also called the product's function and is expressed by establishing the functional unit.

The functional unit describes:

1. a quantity (number, volume or area)
2. a duration (lifetime or a chosen period of time)
3. a quality or properties.

For example, some drainpipes are made of plastic.To compare drainpipes made of PVC and PP (polypropylene), you must ensure that the pipes have the same dimensions.

Today, milk is sold in 1-litre cardboard cartons or in 2-litre plastic bottles. The consumers may find a 2-litre bottle difficult to handle. On the other hand, it has a better closing mechanism than the cardboard carton. In other words, some consumers will consider that the two products have the same quality, while others will not - even though both products deliver 500 litres of milk per year to the family.

It is thus not the product itself that you should focus on, but its function. If you can describe clearly the same function for two products you want to work on, you can also carry out a real comparison.

Examples of functional units are shown in example 1.

Example 1:
Functional units for various products

1.2 Preparation of list of materials and substances

Prepare a material specification to get a systematic overview of the materials and substances that will form part of the finished product. For each material or substance, indicate the quantities (kg or %-weight) in the product.

If the product is fairly simple and consists of non-composite materials and substances, you can set up the material specification directly, as illustrated in example 2.

Example 2:
Material specification for a thermos flask

If, on the other hand, the product is fairly complex, with many components, it may be helpful to set up a so-called list of parts for the product as the basis for the material specification.

In the list of parts you divide the product into different components, which you then subdivide if they comprise several parts.

From your knowledge of the materials used in the individual components, you can sum up the total use of the materials or substances of which all the components consist (see example 3).

You should make a determined effort to procure information about the largest parts (components/substances) used in the product.

You can try to obtain any data you lack concerning the composition of components, materials and/or substances either through suppliers or by assessing the product on the basis of your knowledge of other products. If the suppliers cannot tell you in what quantities the individual materials are used, you can find this by weighing the individual components.

A possible procedure for gathering data from suppliers is as follows:

	Establish personal contacts at the relevant companies
	Explain the purpose of your enquiry and what the data are going to be used for
	Send precise questions
	Follow up on the personal contact
	In many cases, you may have to pay a visit in order to assist the supplier and avoid misunderstandings.

If some of your suppliers have introduced environmental management or some other form of systematic environmental work, start with them because that is where you are most likely to be able to procure data.

Example 3 shows a list of parts and a material specification for a pump.

It will be seen that the pump consists of a cabinet, which in turn consists of a number of components, including a tank, a strap and two drain plugs. The tank is made of 1143 g stainless steel, the strap is made of 190 g stainless steel, and the two drain plugs are made of in all 45 g fibre reinforced PPE. At the bottom of the table, all identical substances and materials are added together, so that you get an overview of the amount of material, e.g. stainless steel, used in the whole pump.

You then enter all the data on materials and constituents obtained by setting up the list of parts and material specification in the flow diagram with inputs and outputs (see example 6) and carry them forward to the matrix form (see example 7).

Example 3:
List of parts and material specification for a pump

1.3 Preparation of flow diagrams/process tree

First, it is important to get an overview of:

1. the processes that the product passes through
2. the inputs and outputs during the product's life cycle.

Start by roughly sketching the product's life cycle and then add more and more detail. By working from level 1 to level 3 below, you get a flow diagram that shows in detail all process steps/activities and all inputs/outputs in each of the phases of the product's life cycle from production of raw materials to disposal.

1.3.1 Level 1 Prepare a flow diagram showing roughly the life cycle of the product.

You illustrate the product's life cycle by drawing the various phases in the life cycle:

	material phase
	production phase
	use phase
	disposal phase
	transport phase.

Example 4 shows a general flow diagram for a pump.

Example 4:
General flow diagram for a pump – level 1

1.3.2 Level 2

Add to the general flow diagram a description of the process steps through which the product passes in each phase.

Then prepare a drawing showing the process steps that take place in each phase.

It is a good idea to start by preparing drawings covering the process steps in your own company, because you know most about them. If you understand the processes that take place at, for example, suppliers of subcomponents, you can enter them as well; otherwise, in the first instance, you must simply add the name of the subcomponent.

Example 5.
Detailed flow diagram showing the individual process steps for each phase of the life cycle of a pump – level 2

Enter the inputs and outputs for each "box"/step in the flow diagram. Start with what is called level 1 above.

Remember that you can often indicate the main flows without much detailing. Most of the production personnel know where "the shoe pinches" - and so do suppliers.

Inputs are, for example:

	raw materials, materials and chemicals
	energy consumption
	water consumption
	ancillaries, e.g. degreasing agents, lubricants, etc.

Outputs are, for example:

	atmospheric emissions
	discharges to water
	waste quantities.

In addition, you should note any health effects, e.g. chemical impacts, noise or dust problems, in the process tree.

Remember also to consider the need for operation and maintenance of the product in the use phase and the materials and substances used for that.

In the case of the disposal phase it is important to consider and note whether the whole of the product is disposed of in the same way or whether some parts are disposed of in a different way. For example, one can envisage large metal parts being separated and sent for recycling, while the rest of the product goes for incineration.

Start by outlining inputs and outputs at level 1 (see example 6). If you go into too much detail when establishing the first overview, you risk suffering data death. If you have information at a more detailed level (see example 5), e.g. via an environmental management system, it seems obvious to use it.

Example 6 illustrates a process tree with inputs and outputs for the production phase (level 1).

Example 6:
Flow diagram for pump with inputs and outputs

1.4 Data collection

You need to have an idea of the size and size ratios of the inputs and outputs in order to judge which environmental impacts are important, seen in a life cycle perspective.You therefore need to collect data for the inputs and outputs you have entered.

1.4.1 Where to find data

Start by collecting the easily accessible data:

	in electronic registration systems that you have built up in connection with other environmental work or in connection with the implementation of environmental management
	in product specifications, suppliers' material safety datasheets for use and technical datasheets
	in environmental approvals, inspection reports or similar
	from employees in the production department, the development department or the purchasing department
	from suppliers and customers.

A company or supplier often does not know what it "costs" in energy terms (energy content per kg material) to produce materials and substances. If you are unable to procure the necessary information, you may find it in reference books or databases.

If you have "Manual on Environmental Assessments", you will find some of the data you need there, together with some rules of thumb for estimating figures that you lack. If you have access to the EDIP PC tool, you will find there a unit process database with information about what it has "cost" in energy terms to produce a number of substances and materials.

1.4.2 Lifetime

As mentioned under the explanation of the functional unit, besides determining the size of the various inputs and outputs, it is important to determine the lifetime (e.g. number of operating hours or years) of the product. The product's lifetime is of great importance, particularly when looking at the environmental impact from two different products with the same function.

If one develops a new product or modifies an existing product, e.g. by substituting materials, it is important to investigate whether that affects the lifetime of the product. A shorter lifetime represents an environmental impairment.

1.4.3 Breaking down flows

You may encounter situations in which data cover the production of several products - for example, if you make many types of products but only record the total energy consumption for lighting and heat or if you calculate the total consumption of cooling water for two process lines in which different items are made.

In such cases, you need to break these material, energy, emission or waste flows down to distribute the figures between the product you are investigating and other products.

The most natural breakdown is to look at the quantity of the product in relation to the others. This can be done on the basis of the value of the products. Choose the breakdown method that seems most natural for you and for which you have data.

1.5 Completing a MECO form

When you have collected and entered input and output data in the flow diagrams, you must summarise the data in a MECO form in order to create an overview of the data collected.

A MECO form is as shown below:

Materials, M:

Under materials, indicate for each phase of the product's life cycle:

	the materials (resources) and substances used directly in the product (i.e. remains in the product for the rest of its life cycle) and the quantities of waste produced (minus chemical waste, which must be listed under chemicals)
	water consumption.

The reason for listing the quantities of waste under materials is that the waste is regarded as a potential resource. If, for example, there are metal shavings from fabrication of the rotor and the shavings are collected because they can be sent for recycling, the metal is treated as a resource that can be used in another product. The metal must therefore be credited to the pump, i.e. it is deducted from the total material consumption.

Energy, E:

Under energy you list the forms and quantities of energy used in the different phases of the life cycle, i.e. whether electricity, oil, natural gas or other form of energy is used and, if so, in what quantity (kWh or MJ). You will find it easier to obtain an overview of the size of the consumption in the various phases if you convert the consumption of the individual forms of energy into the same unit.

Remember that energy is generated during waste incineration and that this energy must be credited to the pump.You do that by deducting it from the total energy consumption, thus entering it as a negative energy consumption under disposal in the MECO form.

Chemicals, C:

Chemicals cover:

	use of chemical ancillary substances/products, e.g. lubricants, cutting oil or cleaning agents and
	atmospheric emissions and emissions to water, e.g. carbon dioxide and nitrogen oxides to the air or phosphates and heavy metals to water.

Other, O:

Other should include health factors, e.g. noise. Besides that, land use may be a parameter, e.g. in the case of agricultural production or dam building for energy production, where large areas of land are used.

Example 7 illustrates a completed form with input and output data for a pump.

Se her!

Example 7.
Completed matrix for a pump

1.6 Further work

In the MECO form, the company's data are collected in a clear way related to the individual phases of the life cycle and the types of data (materials, energy, etc.).

The MECO form gives a first indication of where the significant environmental impacts occur and reveals where data are lacking.The MECO form can also be used for a first assessment of the product or for a first comparison of products.

The next step is to incorporate what you know about the environmental significance of using raw substances and energy and of discharging substances to water and atmospheric emissions.That means that you have to translate your data on inputs and outputs into environmental impacts and then assess the importance of these.

This translation and assessment lie outside the scope of this manual.We recommend that you go on to "Manual on Environmental Assessment of Products" (see the references). This manual tells you how to carry out an assessment on the basis of a MECO form and how to continue if you want to use a PC tool.

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