Hazardous Area Assessment for Distilleries

Engineer the Hazard.
Don’t Assume It.

Operating a distillery means working with ethanol — and that means managing a potentially hazardous atmosphere.

A Hazardous Area Assessment for distilleries identifies where ethanol vapours may create an explosive atmosphere and determines the extent of the hazardous area around your distilling, transfer, storage and bottling operations.

But not every distillery presents the same risk.

At HHH Distill, we take an engineering-led approach to Hazardous Area Assessment. Rather than simply assuming the extent of the hazard, we calculate potential ethanol releases, consider ventilation and operating procedures, and determine the actual conditions within your distillery.

The objective is simple:

Create a safe, compliant distillery without unnecessarily over-engineering it.

Does Your Distillery Need a Hazardous Area Assessment?

Distilleries handle ethanol, a flammable liquid capable of producing potentially explosive vapour-air mixtures.

In Australia, electrical installations are governed by AS/NZS 3000, commonly known as the Wiring Rules.

Section 7.7 addresses electrical installations in hazardous areas and refers to AS/NZS 60079.10.1 for the classification of areas where flammable gases or vapours may be present.

For a distillery, this means the operation needs to be assessed to determine where hazardous atmospheres could occur and how those areas should be classified.

A proper assessment doesn't simply look at the still.

It considers the way ethanol moves throughout your operation.

This can include:

  • Distillation

  • Ethanol and spirit transfer

  • Still filling and emptying

  • Spirit collection

  • Storage

  • Bottling

  • Potential spills

  • Vents and pressure-relief points

  • Equipment failure scenarios

  • Ventilation

  • Operating procedures

Every distillery is different, which is why the assessment needs to consider the actual process and facility.

What Is a Hazardous Area Classification?

A Hazardous Area Assessment determines whether potentially explosive concentrations of ethanol vapour may occur and, if so, where.

These areas may be classified into different zones depending on the likelihood and duration of an explosive atmosphere being present.

Zone 0

An area where an explosive atmosphere is present continuously or for long periods.

This would typically apply to the internal space of equipment or containers containing flammable ethanol mixtures under relevant conditions.

Zone 2

An area where an explosive atmosphere is not expected during normal operation and, if it does occur, is expected to exist only for a short period.

Zone 1

An area where an explosive atmosphere may occasionally occur during normal operation.

Depending on the design and operation of the distillery, this could potentially include areas surrounding particular ethanol release points.

Non-Hazardous Area

An area where the assessment determines that an explosive atmosphere requiring hazardous-area classification is not expected.

The classification — and importantly, the physical extent of each zone — can have significant implications for the design and cost of your distillery.

Why Hazardous Area Classification Matters

The Hazardous Area Assessment doesn't just produce another compliance document.

It can influence how much your distillery costs to build or upgrade.

Electrical equipment installed within hazardous zones may need to comply with specific explosion-protection requirements.

Specialised equipment can include:

  • Electrical motors

  • Heating elements

  • Lighting

  • Switches

  • Junction boxes

  • Fans

  • Sensors

  • Instrumentation

  • Control equipment

Explosion-protected equipment can cost considerably more than conventional electrical equipment.

This creates an important engineering question:

How large does your hazardous area actually need to be?

If an assessment is unnecessarily conservative, a distillery may potentially be required to install specialised equipment across a larger area than necessary.

Getting the classification right therefore matters for both safety and capital cost.

The HHH Distill Approach

We Calculate the Actual Hazard

There are simplified approaches that may be used in some circumstances when assessing smaller distilleries.

HHH Distill takes a more detailed engineering approach.

We calculate potential ethanol releases associated with the actual distillation process and use the methodologies contained within the relevant standards to assess how those releases could affect the surrounding atmosphere.

This allows us to understand the potential hazard rather than simply presume it.

Our assessment can consider:

  • How much ethanol vapour could potentially be released under identified operating or failure scenarios?

  • Could ethanol vapour accumulate within the distillery and at what concentration?

  • How effectively is ethanol vapour diluted and removed from the space?

  • Where could ethanol potentially enter the atmosphere during transfer, distillation, collection, storage or bottling?

  • Can procedures be changed to reduce the likelihood or magnitude of a release?

  • Could changes to equipment or process design reduce the hazardous area?

    The calculations and assessment methodology can then be documented, creating a transparent engineering basis for the resulting classification.

Ventilation Can Change the Equation

Ventilation is one of the important factors affecting the extent of a hazardous area.

The relationship is relatively straightforward:

Potential ethanol release + available ventilation = potential ethanol concentration.

But simply specifying more ventilation isn't necessarily the best engineering solution.

HHH Distill can perform sensitivity analysis to examine how different ventilation rates influence hazardous-area extent.

This allows us to consider questions such as:

  • What happens if ventilation capacity is increased?

  • Could a release point be vented directly outside?

  • Could changes to the process reduce potential vapour release?

  • Could operating procedures change the classification?

  • Could independent engineering controls create a non-hazardous area around particular equipment?

Instead of treating the first assessment as the final answer, we can take an iterative engineering approach.

Assess.

Calculate.

Improve.

Reassess.

The aim is to identify an appropriate combination of equipment design, operating procedures and engineering controls that delivers the required level of safety without unnecessary complexity.

A Cheaper Assessment Doesn't Necessarily Mean a Cheaper Distillery

This is one of the most important considerations when planning a new distillery.

A simplified assessment may initially cost less.

But the assessment itself is only one part of the cost.

If a conservative classification creates unnecessarily large hazardous zones, considerably more specialised electrical equipment may subsequently be required.

That can affect the cost of:

  • Electrical installation

  • Ventilation

  • Heating

  • Lighting

  • Instrumentation

  • Control systems

  • Future modifications and expansion

HHH Distill looks at the bigger picture.

We use engineering intelligence before you commit to capital expenditure.

A detailed assessment may identify opportunities to safely reduce hazardous-area extents through better design, ventilation, operating procedures or engineering controls.

The result can be a distillery that is both safe and economically designed.

Hazardous Area Assessments for New and Existing Distilleries

A Hazardous Area Assessment can be valuable at several stages of a distillery's life.

Planning a New Distillery

Assessing hazardous areas early allows safety and compliance requirements to influence the facility design before equipment and electrical systems are installed.

This is generally much easier than attempting to modify the facility afterwards.

Expanding Production

Greater production volumes or changes to storage, transfer and bottling processes may introduce different release scenarios.

Installing or Upgrading a Still

Changing still capacity, heating systems, ventilation or processing methods may affect the hazardous-area classification.

An assessment can help determine what needs to change before installation begins.

Reviewing an Existing Distillery

If your existing hazardous-area classification appears overly conservative, or you're facing substantial costs for explosion-protected electrical equipment, a detailed engineering assessment may identify alternative solutions.

Engineering Distilleries From Experience

HHH Distill doesn't approach Hazardous Area Assessment in isolation from the distillation process.

We understand how distilleries actually operate.

Our knowledge of still design, ethanol handling, process engineering and distillery operations allows us to look at the relationship between the equipment, the process, the operator and the environment.

That matters because hazardous-area classification isn't simply about drawing circles around equipment.

It's about understanding how and where ethanol can actually be released.

Learn More About Hazardous Areas in Distilleries

If you'd like to understand the technical principles behind hazardous areas, ethanol vapour, Zone 0, Zone 1 and Zone 2 classifications, HHH Distill has also prepared a detailed technical introduction:

Read: An Introduction to Hazardous Areas in a Distillery

This technical article explains why hazardous areas exist within distilleries and explores some of the engineering considerations that can influence their classification.

Need a Hazardous Area Assessment for Your Distillery?

Whether you're designing a new distillery, installing a still, expanding production or reviewing an existing hazardous-area classification, getting the engineering right at the beginning can prevent unnecessary costs later.

HHH Distill can assess your distillation processes, potential ethanol releases, ventilation and operating controls to determine the appropriate hazardous-area classification for your facility.

Don't simply assume the hazard.

Calculate it. Understand it. Engineer it.

Talk to HHH Distill about a Hazardous Area Assessment.