Application of Control Charts to Process Safety Events

Historically, there has been a significant increase in the desire to create and implement a data-driven culture within companies. Terms such as Big Data, Data Science, Data Analysis, have been gaining more and more ground to help support this process of transforming large volumes of data into strategic drivers.

With the increased use of information to support decision-making, the focus on ensuring that the right data is being presented is becoming even more a priority. In January 2021, Ilumeo, a data science consultancy, published some interesting statistics on its website:

According to Gartner, an average of US$15 million a year is spent on wrong decisions in companies and, according to Experian, 90% of companies are affected by this problem [...]

An IBM study revealed that 1/3 of business executives don't trust their data and that, on average, 32% of their data is wrong. Another study, by Forrester, shows that 1/3 of data analysts spend more than 40% of their time reviewing data manually, field by field, looking for quality problems. Precisely because of the lack of trust.

Considering this scenario, Vale - a Brazilian multinational mining company and one of the largest mining companies in the world, with a staff of approximately 185,000 people (including its own professionals and contractors) - which deals with various fronts and initiatives focused on data and has a specific corporate area whose main objective is to capture and transform Health, Safety, Environment and Operational Risk/Process Safety (HSEOR) information into strategic assets through a data-oriented culture, created the Data Quality area, with a focus on guaranteeing the quality of HSEOR data.

This area arose because of the need to clarify the quality and reliability of the information on these issues that exists in the company today. Ensuring the quality of this data also ensures the optimization of time and processes, increasing the chance of good results and reducing the risk of failures. The Control Chart is one of the methods used to achieve this goal.

The local safety areas at Vale have been increasingly working on plans to reduce the occurrence of Process Safety Events. The aim of the corporate quality area is to provide support so that these areas can understand where to act to prevent a new event from happening. To this end, the control chart was implemented. Its methodology consists of identifying the acceptable limits for the process under analysis. Two ways of defining these limits were applied in this study: the traditional method which consists of calculating the Upper and Lower Limits according to the behavior of the process; the limits were also defined following the target values stipulated for each area in the process under study. The second method was more effective in detecting deviations for action. By mapping the weekly behavior of events in each area, it is possible to identify which week is outside the process.

Each week, a process is carried out which culminates in the automatic triggering of an email alerting us when a certain area deviates from the existing standard. These emails make it possible to carry out studies to identify the causes associated with this deviation more immediately, preventing the behavior from continuing for more than a week.

By having the teams work to discover the causes and eliminate them, given the results achieved by applying the Control Charts to the Process Safety theme, it will be possible to minimize risks, improve worker safety and protection against fires and explosions, for example. The great expectations for the study are to extend the application to the other themes in the area (Occupational Health, Occupational Safety and Environment) in order to achieve greater safety in our operations and to create an environment for sharing the causes already identified so that other areas can use them as learning.