This step is relevant to sections 4.5.5 and 4.6.1 of the ISO 50001-2011 standard.
Significant deviations in energy performance are defined by your organization. When a significant deviation occurs, your organization must investigate and provide an appropriate response and record the results of the response.
There are 3 tasks for identifying and responding to significant deviations and recording the results:
The data you collect by monitoring and measuring the key characteristics of operations that determine energy performance (see Step 4.1) is used to identify significant deviations. Your organization determines what will be considered a significant deviation but, in general, it is a departure from a level of energy performance that is acceptable, defined or expected. A deviation may be identified by a specific level of variation or can be evaluated by knowledgeable personnel to determine if it is significant and if action is required. Examples of methods for specifying significant deviations can include:
Once you determine the method(s) for identifying a significant deviation, you must determine the criteria you will use to evaluate if a significant deviation occurs. Your organization determines the method and criteria in accordance with what you deem acceptable or unacceptable relative to the impact on energy performance. As an example:
Your organization may decide that if electricity consumption for the current month increases by more than 10% over the previous month, that will be considered a significant deviation. Alternatively, you may decide that you want to be more proactive about improving energy performance and set a 5% or more increase as the deviation to be considered significant.
A significant deviation can be an improvement as well as a decline in energy performance. An improvement in energy performance is a deviation (although generally desired) and you must investigate if it is deemed significant (see Step 4.2.2). For example:
In the previous example, your organization decided a 5% or more increase in energy consumption for the current month compared to last month will be considered a significant deviation. Alternatively, the criteria could be any change in consumption of 5% or more comparing the current month to last month will be considered a significant deviation. In this case, a 5% or more improvement would require that your company investigate the deviation and respond.
Consider documenting the criteria for significant deviations within the energy measurement plan (see Step 4.1).
Significant deviations are also related to operational and maintenance controls which is discussed in Step 3.5.1. The methods for identifying significant deviations relative to operational and maintenance controls would be similar to the process for key characteristics discussed here. Operational and maintenance criteria could be a factor in the determination of significant deviations and Step 3.5.1 lists significant deviations that could be the result of operational or maintenance issues.
Once you have set the criteria for determining a significant deviation for each of the key characteristics that are measured and monitored, you must investigate and respond if the deviation occurs. Many organizations use the corrective action process (see Step 4.5) to address significant deviations. This works well in many organizations as the corrective action process will have procedures in place for addressing nonconformities such as:
A well developed and implemented corrective action process can be an effective tool for investigating significant deviations. However, the ISO 50001 standard only requires that you investigate and respond to significant deviations. It does not require that they be addressed by your corrective action process. You may decide to investigate significant deviations outside the corrective action system. A formal investigative process is not required; however, consider the corrective action steps described above as a best practice.
The investigation addresses normal operation, as well as evaluation of energy use and consumption expected as the result of process changes or implementation of improvement opportunities. As an example:
You may decide that improvements achieved as the result of planned activities will not be considered significant deviations if the actual results are in line with pre-project estimates. On the other hand, if there is a difference of 5% or more between the actual and estimated results, you may decide this is a significant deviation. If the results were better by 5% or more, this would require an investigation into why the results were better than the estimates.
Significant deviations that result in improved energy performance can be analyzed for actions to be replicated in other energy systems.
You must develop a response as a result of the investigation. Your response will likely be some type of action that is required to alleviate a significant deviation that results in declining energy performance or reproducing the conditions in other areas if performance is improved. However, note that a decision not to respond is a legitimate response. This may occur if the significant deviation:
You must record the results of the investigation and the response(s). If your corrective action process is used for investigating significant deviations, then the record requirements would already be addressed (ISO 50001 requires records of corrective actions). Otherwise, consider developing a record process in line with the ISO 50001 records requirements (see Step 3.3). There are no specific record requirements but items to consider recording include:
The following resources provide information needed to understand EnMS documentation and decide what documents and records are needed for your EnMS.
The following resource is designed primarily for organizations that plan to seek third-party certification to ISO 50001-2011. It helps you understand how to check and use your EnMS records to demonstrate the implementation of the system (you are doing what you say), and the effectiveness of the system in generating the intended results (what you are doing is working).
