Hazardous Area Classification - November 2025

About Hazardous Area Classification:

Hazardous Area Classification (HAC) is the assessed division of a facility where releases of flammable liquids and gases can occur, either intentionally or accidentally, into hazardous areas and non-hazardous areas. The Energy Institute Model Safe Code of Practice 15, Area Classification for Installations Handing Flammable Fluids (EI15) guidance is relevant to all industry sectors where the classification of potential flammable zones is a requirement.

In this course, delegates will develop the key knowledge they need to identify how flammable atmospheres can form and methods for classifying them into zones. The classification of zones then highlights where ignition sources must be controlled and is a key requirement of demonstrating a basis of safety.

This course will follow the new edition of The Energy Institute Model Safe Code of Practice 15, Area Classification for Installations Handing Flammable Fluids (EI15) guidance.

Key benefits:

• The course is based on the Energy Institute’s renowned EI15 guidance document
• Learn from an expert tutor, who was involved in the production of the EI15 guidance and has extensive experience of carrying out HAC studies for many companies in a wide variety of industry sectors
• Delegates will receive a Hazardous Area Classification training certificate from the Energy Institute.

Learning outcomes:

• To understand the methodology in the EI15 guidance
• To be capable of applying the EI15 guidance in practice
• To know when to use the EI15 guidance for relevant applications.

The EI15 is one of the Energy Institute’s most popular publications, being downloaded over 2000 times. It is recognised as de-facto guidance worldwide and recommended as industry guidance in IEC 60079-10-1:2021 and in the DSEAR Approved Code of Practice, L138. The course will train delegates in all aspects of EI15 and reinforce the learning through the use of practical exercises and examples. The session will be delivered by an engineer who is experienced in hazardous area classification and who is an active member of the Energy Institute working group who authors and edits the guidance.

Who should take this course?

• This course is suitable for anybody who is involved with process safety such as: risk analysts, chemical, mechanical and design engineers
• Delegates should have a basic understanding of flammable products, area classification techniques and relevant standards and guidance.

Course overview:

Introduction to legislation and standards

• Delegates will be introduced to the statutory requirements for HAC in the UK and internationally.

 Properties of flammable materials

• Delegates will learn about the properties of materials and their flammable and combustible characteristics.

 Key area classification concepts

• Minimum volumes for the application of HAC
• The definition of the grades of release
• The relationship between the grades of release, ventilation and the resulting zone
• The concepts of blanket and point zones
• The procedures and methodology in carrying out a HAC study.

Techniques of area classification

• Point Source approach - Covering sample points, atmospheric vents, pig launchers and pools of liquids
• Risk Based approach - How the Risk Level of an installation can be determined. The use of hole sizes in determining the zone 2 extents from secondary releases from pumps, pipework and compressors etc
• Direct Example approach - Particular attention will be given to storage tanks, road tanker operations and offshore well heads. How Direct Examples can incorporate the Point Source approach.

Ventilation

• Delegates will be introduced to the key change in EI15 on the effect ventilation has on releases. Its influence on zones will be considered in diluting releases both outdoors and inside enclosures.

Impact of external variables to area classification­­

• Throughout the training course, delegates will be familiarised with the effects of changes to external variables. The delegates will learn how the application of the direct examples and the risk based approach will change depending on the ambient or storage temperature and the resulting change in petroleum class or fluid category.

Throughout the course, there will be the opportunity for the delegates to practice the techniques on a real world example. A detailed practical exercise will be completed to reinforce the learning from each section of the training. This practical element will help translate the learning into a real world scenario.