ISO 14001:2026 for Auditors > Clause 9.1
Explained: Monitoring, Measurement, Analysis and Evaluation
Clause 9.1 of ISO 14001 asks an organisation to monitor, measure, analyse and evaluate its environmental performance. In plain English, this means deciding what information is needed to understand whether the Environmental Management System is working, collecting that information reliably, and using it to make decisions.
What is ISO 14001 Clause 9.1 trying to achieve?
Clause 9.1 is about evidence-based environmental management.
The organisation should not guess whether the EMS is working. It should use suitable data, observations, checks and evaluation methods to understand environmental performance.
This includes deciding:
- what needs to be monitored and measured;
- how monitoring and measurement will be carried out;
- what methods are needed to ensure valid results;
- what criteria will be used to evaluate performance;
- when monitoring and measurement will happen;
- when results will be analysed and evaluated;
- what documented information will be retained as evidence.
The purpose is to turn EMS activity into useful information.
Why monitoring and measurement matters in an EMS
Without monitoring and measurement, the organisation may not know whether its controls, objectives and compliance arrangements are working.
Good monitoring and measurement can help answer questions such as:
- Are significant environmental aspects being controlled?
- Are objectives on track?
- Are emissions, waste, energy or water trends improving or worsening?
- Are inspection checks being completed?
- Are contractors meeting environmental requirements?
- Are emergency arrangements being tested?
- Are compliance obligations being fulfilled?
- Are corrective actions reducing repeat problems?
The EMS needs reliable information so the organisation can make sensible decisions instead of relying on vibes and crossed fingers.
What does ISO 14001 expect?
ISO 14001 expects the organisation to evaluate its environmental performance and the effectiveness of the EMS.
To do that, the organisation should determine:
- what needs to be monitored and measured;
- the methods for monitoring, measurement, analysis and evaluation;
- the criteria used to evaluate environmental performance;
- appropriate indicators where relevant;
- when monitoring and measurement will be performed;
- when results will be analysed and evaluated;
- what documented information will be retained as evidence.
The organisation should also ensure that monitoring and measuring equipment is calibrated or verified where needed.
Clause 9.1.1 — General performance evaluation requirements
Clause 9.1.1 is the general part of Clause 9.1. It sets out the basic requirements for monitoring, measurement, analysis and evaluation.
It asks the organisation to decide what performance information matters and how it will be gathered and evaluated.
For learners and auditors, Clause 9.1.1 is best understood as the “performance data” requirement. It is about making sure the organisation has reliable information on EMS performance, not just scattered records.
Auditor tip
When auditing Clause 9.1.1, ask how the organisation decided what to monitor. Monitoring should normally link back to environmental aspects, objectives, operational controls, compliance obligations, risks and opportunities.
Monitoring, measurement, analysis and evaluation are not identical
These words are related, but they do not mean exactly the same thing.
Monitoring usually means observing, checking or tracking something over time.
Measurement usually means assigning a value or quantity, such as litres, tonnes, kilowatt-hours, percentages or emission levels.
Analysis means looking at the information to identify trends, causes, changes, patterns or meaning.
Evaluation means judging the result against criteria, requirements, objectives, expectations or intended outcomes.
Simple example
A company measures electricity use each month. It analyses trends against production levels and weather changes. It evaluates whether energy-reduction objectives are being achieved and whether further action is needed.
What should be monitored and measured?
The organisation should monitor and measure what is needed to evaluate environmental performance and EMS effectiveness.
This may include:
- significant environmental aspects;
- environmental objectives;
- energy use;
- water use;
- waste generation and recycling rates;
- emissions to air;
- discharges to water or sewer;
- fuel consumption;
- spill incidents and near misses;
- environmental complaints;
- inspection results;
- maintenance of environmental controls;
- contractor environmental performance;
- training or awareness completion;
- audit findings and corrective action status.
The exact indicators should suit the organisation’s context, scope, aspects, compliance obligations and objectives.
Monitoring significant environmental aspects
Significant environmental aspects should often be reflected in monitoring and measurement.
For example:
- fuel use may be monitored through litres used, vehicle mileage or emissions data;
- waste may be monitored by waste stream, weight, cost or contamination rate;
- water use may be monitored through meter readings or process data;
- chemical storage may be monitored through inspection records and incident trends;
- emissions may be monitored through sampling, equipment readings or permit reports;
- contractor activity may be monitored through inspection results and incident records.
Auditors should check whether significant aspects have appropriate performance indicators or control checks.
Monitoring environmental objectives
Environmental objectives should be monitored so the organisation can understand progress.
This may involve:
- baseline data;
- targets or intended outcomes;
- milestones;
- responsible persons;
- planned actions;
- progress updates;
- performance indicators;
- evidence of completed actions;
- evaluation of results.
If objectives are not monitored, they can become decorative. Lovely to look at. Not doing much.
Monitoring operational controls
Monitoring is not only about environmental output data. It can also be about checking whether operational controls are being carried out.
Examples include:
- bund inspections;
- spill-kit checks;
- waste area inspections;
- filter or extraction maintenance;
- contractor permit checks;
- equipment calibration checks;
- drain protection checks;
- emergency equipment inspections;
- shutdown checks for energy control;
- supplier or contractor performance reviews.
This type of monitoring helps show whether controls are operating as planned.
Methods should produce valid results
ISO 14001 expects the organisation to use methods that produce valid monitoring, measurement, analysis and evaluation results.
This may involve considering:
- accuracy of data sources;
- calibration or verification of equipment;
- sampling methods;
- frequency of monitoring;
- competence of people collecting data;
- consistency of calculations;
- clear definitions of indicators;
- data review and approval;
- handling of missing or abnormal data;
- record retention and traceability.
The more important the information is for compliance or decision-making, the more important data reliability becomes.
Monitoring and measuring equipment
Where monitoring or measuring equipment is used, the organisation should ensure it is calibrated or verified where necessary.
Relevant equipment may include:
- meters;
- weighing equipment;
- emissions monitoring equipment;
- sampling equipment;
- pH meters;
- flow meters;
- noise meters;
- temperature sensors;
- monitoring probes;
- software or data systems used for environmental reporting.
Auditors should check whether equipment accuracy matters and, if so, whether calibration or verification evidence is available.
Criteria and indicators for environmental performance
The organisation should determine the criteria it will use to evaluate environmental performance.
Criteria may include:
- legal or permit limits;
- environmental objectives;
- internal targets;
- corporate requirements;
- customer requirements;
- industry benchmarks;
- previous performance;
- acceptable operating ranges;
- planned action completion;
- risk-based thresholds.
Indicators may include quantities, rates, ratios, percentages, incident numbers, completion rates or qualitative evidence.
Simple example
Waste performance could be evaluated using total waste weight, recycling percentage, contamination rate, waste cost, waste per unit produced, and completion of waste-area inspections.
Analysis and evaluation should lead to decisions
Collecting data is not enough. The organisation should analyse and evaluate results.
This may include asking:
- Are results improving, worsening or stable?
- Are objectives on track?
- Are controls working?
- Are compliance obligations being met?
- Are there recurring issues?
- Are results affected by changes in production, weather, staff or contractors?
- Are current indicators still useful?
- Is corrective action or improvement needed?
Analysis and evaluation should feed into management review, internal audit planning, operational control, corrective action and continual improvement.
Communication of environmental performance
ISO 14001 expects relevant environmental performance information to be communicated internally and externally, as identified in the organisation’s communication process and required by compliance obligations.
Internal communication may include:
- performance dashboards;
- team briefings;
- management meetings;
- objective progress updates;
- incident trends;
- audit findings;
- management review reports.
External communication may include:
- customer reports;
- regulatory submissions;
- certification audit evidence;
- corporate sustainability reports;
- responses to interested party requests;
- contractual environmental reporting.
Environmental performance information should be accurate, reliable and suitable for the audience.
Documented information for Clause 9.1
The organisation should retain appropriate documented information as evidence of monitoring, measurement, analysis and evaluation results.
Evidence may include:
- monitoring plans;
- measurement records;
- environmental performance reports;
- objective progress records;
- inspection checklists;
- calibration or verification records;
- waste, energy, water or emissions data;
- incident and complaint trend records;
- contractor performance records;
- data analysis summaries;
- management review inputs;
- actions arising from evaluation.
Records should be retained in a way that allows the organisation to demonstrate what was measured, when, how, by whom, and what the results meant.
Practical implementation guidance
A practical monitoring and measurement process should answer:
- What are we monitoring or measuring?
- Why are we monitoring it?
- Which aspect, objective, control or obligation does it relate to?
- What method will be used?
- How often will monitoring happen?
- Who is responsible?
- What equipment or data source is used?
- How will results be checked for validity?
- What criteria or target will results be evaluated against?
- Where will records be retained?
- What happens if results are outside expectations?
This does not need to be complicated. The key is that monitoring and measurement should be purposeful, reliable and used.
What auditors typically look for
Auditors look for evidence that monitoring and measurement arrangements are planned, suitable and used to evaluate EMS performance.
Evidence may include:
- monitoring and measurement plan;
- environmental performance indicators;
- records of energy, water, waste, fuel or emissions;
- inspection records;
- maintenance and equipment checks;
- calibration or verification records;
- objective progress reports;
- analysis of trends;
- management review inputs;
- corrective actions arising from results;
- communication of environmental performance information;
- interviews with people responsible for collecting and using data.
Auditor tip
Pick one environmental objective or significant aspect and follow the data trail. What is measured? Who measures it? How do they know the result is valid? Who reviews it? What happens when performance is not acceptable?
Common weaknesses in Clause 9.1
- data is collected but not analysed;
- monitoring does not link to significant aspects or objectives;
- methods are unclear or inconsistent;
- equipment is not calibrated or verified where necessary;
- performance criteria are not defined;
- results are reviewed too late to support decisions;
- environmental performance information is unreliable;
- monitoring focuses on easy data rather than important data;
- poor results do not trigger action;
- management review receives data but no useful evaluation.
Weak example
“The organisation records electricity, waste and water figures each month.”
This is weak because it does not show why those figures were chosen, whether the methods are valid, whether criteria exist, whether results are analysed, or whether decisions are made from the data.
Better example
“The organisation monitors electricity, gas, water, waste, fuel use, spill incidents and objective progress. Results are reviewed monthly against targets and previous performance. Significant changes are investigated, and findings are reported to management review with actions where needed.”
This is stronger because it shows monitoring, analysis, evaluation and decision-making.
Real-world example: warehouse and distribution company
A warehouse and distribution company identifies fuel use, electricity consumption, packaging waste and spill risk as important EMS issues.
Monitoring and measurement may include:
- monthly fuel use by vehicle or route;
- electricity use by site;
- packaging waste by waste stream;
- waste contamination rates;
- spill-kit inspection completion;
- incident and near-miss trends;
- progress against waste and fuel objectives;
- contractor performance issues.
An auditor could test whether the organisation uses this information to improve route planning, waste segregation, contractor controls and emergency preparedness.
Real-world example: office-based organisation
An office-based organisation may monitor simpler indicators, but Clause 9.1 still applies.
Examples include:
- electricity and gas consumption;
- business travel mileage or emissions;
- paper use;
- IT equipment disposal records;
- supplier environmental checks;
- progress against travel or energy objectives;
- employee awareness completion;
- audit findings and corrective action status.
The organisation should still analyse and evaluate results, even when the EMS is low-risk and relatively simple.
Auditor questions for ISO 14001 Clause 9.1
- What does the organisation monitor and measure?
- How was it decided what needs monitoring and measurement?
- Which indicators relate to significant environmental aspects?
- Which indicators relate to environmental objectives?
- What methods are used to ensure valid results?
- What criteria are used to evaluate environmental performance?
- When is monitoring and measurement performed?
- When are results analysed and evaluated?
- How is monitoring equipment calibrated or verified where needed?
- How are environmental performance results communicated?
- What documented information is retained?
- What actions are taken when results are outside expectations?
Related ISO 14001 clauses
- Clause 6.1.2 — Environmental aspects
- Clause 6.1.3 — Compliance obligations
- Clause 6.2 — Environmental objectives
- Clause 7.2 — Competence
- Clause 7.4 — Communication
- Clause 7.5 — Documented information
- Clause 8.1 — Operational planning and control
- Clause 8.2 — Emergency preparedness and response
- Clause 9.1.2 — Evaluation of compliance
- Clause 9.2 — Internal audit
- Clause 9.3 — Management review
- Clause 10.2 — Nonconformity and corrective action
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This page is part of SQMC’s ISO 14001:2026 guidance library for auditors, managers and QHSE professionals.
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