Practical Environmental Management Systems
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Identifying and understanding how a company interacts with the environment helps to develop an effective EMS to reduce waste and improve environmental performance. This Section explains how to identify environmental aspects and assess their significance. The information gathered during the Initial Review provides a starting point for this part of the EMS. Aspects are the 'cause' of an environmental impact or effect. Environmental aspects also include measures you have already taken to prevent or reduce pollution.
ISO 14001 requires demonstration that all possible environmental aspects have been considered and evaluated.
Companies often find that compiling a list of environmental aspects and impacts and assessing their significance is the most difficult stage of implementing an EMS.
Start by making a list of the various departments on the site, e.g. manufacturing, utilities, stores and engineering maintenance (also include upstream and downstream processing activities such as goods inward, assembly, printing, packaging and dispatch) and then identify the different processes that make up these activities.
Draw a box for each activity and add the inputs and outputs to this diagram. Remember: consider emissions to air, water, and land (as waste or through spills) on the process map - however small they may be. The process map will help to identify all of the environmental aspects and clarify the operations where waste may be arising as well as opportunities for waste reduction. Also consider what happens under abnormal situations, e.g. start-ups, shutdowns and cleaning, as well as the potential for incidents and accidents.
- Non-core processes.
- Refrigerants in cooling and air conditioning
- PCBs in electrical transformers.
Normally these will not escape into the environment, but the EMS should have procedures for dealing with them during maintenance and final disposal.
From the process map, decide which inputs and outputs may interact with the environment and are, therefore, environmental aspects.
Remember: include aspects that are not covered by legislation - they may still be significant.
Impacts cannot be directly controlled - they are generated by the aspects previously identified. An aspect can generate more than one impact and many aspects have indirect impacts. Electricity use (an aspect) has three indirect impacts, i.e. climate change due to carbon dioxide emissions, air pollution from acid gas emissions and resource depletion through fossil fuel use.
The next task is to assess which aspects are significant. Environmental aspects that are judged to be significant are the ones that will be managed by the EMS. The Initial Review should reveal which activities are covered by legislation and/or have a high cost. These will be areas where improvement activities will have a high beneficial environmental impact and significantly reduce costs.
Assessing significance through a formal procedure enables:
- Concentration on taking action to reduce major impacts.
- Effective use of resources.
- Avoiding having to try to deal with all impacts (including insignificant ones).
Section 4.3.1 of ISO 14001 requires identification of significant aspects (those that have a significant impact on the environment) using a formal procedure. ISO 14001 does not specify a set method for assessing the significance of environmental aspects. However, the procedure used to assess significance should be recorded in a systematic manner for future reference. Accredited certifiers will want to see these records.
When assessing significance:
- Be consistent.
- Use criteria that provide a rational basis for the rest of your EMS.
- Record the method and decisions in a systematic manner.
There is no set or prescribed method for assessing the significance of environmental impacts. There are various techniques to assess significance - choose the approach that is the most appropriate to the company. The keys to success are:
- Develop a consistent approach that allows each issue to be clearly treated in the same way.
- Be able to demonstrate and justify the methodology used.
Risk assessment method
This approach uses conventional risk assessment methods to predict the likelihood and severity of outcomes or events. It is similar to the Failure Modes Effects Analysis (FMEA) approach used in quality and design management. It is also similar to some of the risk assessment methods used in Health and Safety. In all these methods, ratings of severity, likelihood and detection are individually assessed and then combined to produce an overall assessment of the risk.
A risk factor rating is assigned to each potential impact after considering the following:
- Hazardous properties.
- Frequency or likelihood of occurrence.
- Presence of sensitive environmental receptors, e.g. people, a watercourse and/or site of special scientific interest.
- Presence or absence of environmental controls, e.g. techniques designed to control or prevent the environmental impact.
For each impact, decide the degree of severity (minor, moderate, major) and how likely it is to occur (unlikely, likely, very likely). A total risk assessment is obtained by combining the severity of the consequences with the likelihood of occurrence for each impact. A numerical rating is given to each, with a negative number indicating an adverse impact.
More details on Risk Assessment for Environmental Aspects and Impacts
Numerical rating/weighting method
This method gives a score to each impact to quantify the importance of different criteria.
Step 1: Normal operating conditions
Each impact is awarded a score under normal operating conditions. These scores reflect the relative importance of major issues such as:
- Environmental damage.
- Interested parties.
Scores are weighted according to the likely effect of the impact. The weighting assigned to each issue is arbitrary but should reflect the company's priorities. Comparing total scores for each impact allows prioritisation of efforts under normal operating conditions.
Step 2: Other operating conditions
Each impact is given a score under other operating conditions such as:
- Abnormal operations.
- Past activities.
- Planned activities.
Allocating scores to these conditions allows the overall importance of the impact to be calculated.
What is significant?
After assessment, an impact is considered significant if the score is above a threshold value. For risk assessment methods, the absolute score is the important value for ranking. For numerical weighting methods, some impacts may be significant in only one category, others in both. Each company can set the scores over which impacts are considered significant but the reasons for the decision should be recorded.
The reasons for decisions should be recorded in a systematic manner for future reference and to show to accredited certifiers.
Written procedure for evaluating significance
The procedure to identify aspects and assess them for significance must be recorded and produce consistent results for each site.
The collection of lists of environmental aspects and evaluation of significance make up the ‘Aspects Register’. This Register should give details of the company's environmental aspects, together with an analysis of their impacts. It should indicate whether an aspect is considered significant and how significant environmental aspects are linked to the EMS.
Remember to assess new projects according to the chosen method and to link the evaluation procedure to the capital expenditure application and authorisation process.
- A written procedure to identify environmental aspects and to evaluate those with significant environmental impacts.
- An Aspects Register.
- Process maps and evaluation tables (the proof of the process).
- An environmental policy.
- Waste Minimisation Pays: Five business reasons for reducing waste (GG125).
- Environmental Management Systems for the plastics industry (GG251).
- Finding and reducing waste in plastics processing (GG277).
Available free from the Environment and Energy Helpline (0800 585 794)
The "Practical Environmental Management Systems" series is designed to give plastics processors an insight into how to implement an Environmental Management System. The series is being published in Polymer Engineering on a monthly basis and is published here after the Polymer Engineering publication. The series is:
Part 1: Clean business = good business
Part 2: Starting out
Part 3: Managing interactions with the environment (This section)
Part 4: The basic EMS system
Part 5: Operating an EMS system
Download the complete series as an Adobe Acrobat file.
Last edited: 11/03/10
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