Electrical Enclosure Pressurisation Systems Guide

Apr 29, 2026

Electrical enclosure pressurisation systems are designed to protect industrial electrical cabinets from dust ingress, internal heat buildup, and contamination-related electrical failure. In harsh site environments, filtered positive pressure airflow provides a cleaner, cooler, and more reliable operating environment for sensitive electrical components.

In this guide, we provide a general overview of what electrical enclosure pressurisation systems are, how they improve cabinet protection and electrical reliability, why more industrial sites are adopting them, and where they are commonly used.

Let’s dive in.

What Is an Electrical Enclosure Pressurisation System?

Electrical enclosure pressurisation systems are dedicated filtered airflow units fitted to electrical cabinets to actively control the environment inside the enclosure. Rather than relying solely on cabinet seals, these systems continuously introduce clean filtered air while maintaining stable internal pressure during operation.

This allows the enclosure to operate as a protected internal space, helping reduce the impact of airborne contamination and excessive heat on sensitive electrical hardware.

A Filtered Positive Pressure Protection System

The system works by drawing in ambient air through a high efficiency filtration assembly before supplying that air into the cabinet. Once inside, the filtered airflow creates slight positive pressure, meaning the cabinet pressure remains above the surrounding atmosphere.

Because air naturally wants to move outward through any small cabinet gaps, dusty external air is far less likely to leak inward. This simple pressure difference forms one of the most effective barriers against long-term contamination.

Common Electrical Cabinets Protected by These Systems

Electrical enclosure pressurisation systems are commonly installed on PLC cabinets, variable speed drive cabinets, motor control centres, automation panels, and remote field instrumentation enclosures.

These cabinets are often located close to conveyors, crushers, wash plants, diesel equipment, or process areas where dust and heat are constant operating challenges.

Electrical Enclosure Pressurisation Systems Improve Cabinet Protection

The biggest advantage of enclosure pressurisation is that it helps create a far more stable internal cabinet environment compared to passive sealed enclosures. Instead of allowing the cabinet to slowly absorb site contamination and trap internal heat, the system actively manages both cleanliness and airflow.

This leads to better long-term electrical reliability and reduced stress on internal components.

Reducing Dust Ingress and Airborne Contamination

Even cabinets that appear sealed can slowly draw in contaminated air through cable penetrations, worn seals, and maintenance openings as internal pressure changes throughout the day.

Positive pressure airflow changes that behavior completely by ensuring filtered air is always moving outward. This greatly reduces the amount of airborne dust, fine particulates, and moisture entering the cabinet over time, helping keep terminals, relays, boards, and drives cleaner.

Supporting Better Cooling for Sensitive Electrical Components

Modern electrical enclosures generate a significant amount of heat from PLC processors, relays, drives, transformers, and power supplies. Without controlled airflow, this heat can remain trapped and push internal temperatures beyond ideal operating levels.

Continuous filtered airflow helps remove that trapped heat and creates a more stable internal operating temperature, reducing thermal stress on sensitive electrical components and lowering the risk of nuisance trips or premature failures.

More Industrial Sites Adopting Electrical Enclosure Pressurisation

Industrial machinery is becoming increasingly dependent on electronic control systems, which means electrical cabinet reliability now has a direct impact on machine uptime.

As site environments become harsher and automation becomes more sensitive, many operations are recognising that standard cabinet sealing methods are no longer enough for long-term protection.

Electrical Cabinet Failures Lead to Expensive Downtime

When contamination or overheating causes electrical faults, the issue often extends beyond a single failed component. Machines may shut down unexpectedly, electricians are called out for troubleshooting, and production can be interrupted for hours or even days.

This makes cabinet protection a reliability issue as much as a maintenance issue.

Proactive Protection Is More Effective Than Reactive Repairs

Rather than waiting for contamination-related failures to occur, many sites are moving toward proactive enclosure protection to keep cabinets cleaner and cooler from the beginning.

Electrical enclosure pressurisation helps reduce the frequency of dust cleaning, electrical repairs, and heat-related component stress, making it a practical long-term upgrade for equipment operating in harsh environments.

Where Are Electrical Enclosure Pressurisation Systems Commonly Used?

Electrical enclosure pressurisation systems are used anywhere industrial electrical cabinets are exposed to airborne contamination, excessive heat, or unstable site conditions.

These systems are particularly valuable in operations where electrical reliability is critical to machine productivity.

High Dust Mining and Processing Environments

Mining operations, quarry plants, crushing systems, wash plants, and bulk handling facilities constantly generate fine airborne particulates that can slowly contaminate exposed electrical enclosures.

In these environments, maintaining positive pressure and filtered airflow helps create a far more reliable cabinet condition over long operating periods.

Remote Industrial Equipment and High Temperature Zones

Remote field automation stations, underground operations, smelters, and process areas often combine contamination risk with elevated ambient temperatures.

Electrical enclosure pressurisation provides both environmental protection and thermal airflow support, helping cabinets maintain cleaner and more stable operating conditions where standard sealed enclosures often struggle.

Keeping Underground Mining Safe with OnGuard!

Oct 14, 2025

Technical

Oct 14, 2025

High-efficiency air filtration system with durable black filters and white PVC piping, designed for improved indoor air quality and ventilation in industrial and commercial facilities.

In underground activities, especially tunnelling and mining, dust exposure and poor air quality are critical health hazards. Limited ventilation, restricted air circulation, and the accumulation of carbon dioxide can quickly create unsafe working conditions for machine operators and crew members. To address these challenges, BreatheSafe designs and installs advanced filtration and pressurisation systems that provide operators with a clean, safe, and comfortable environment even in the harshest underground settings.

The Challenge of Underground Air Quality

Unlike open-air environments, underground worksites have very limited natural ventilation. Dust generated from drilling, cutting, and vehicle movement can remain suspended in the air for long periods.

At the same time, carbon dioxide produced by diesel engines, blasting activities, or human respiration can accumulate within enclosed spaces.

These conditions can cause a drop in oxygen concentration, increase operator fatigue, reduce visibility, and pose long-term respiratory risks. Maintaining air quality in such an environment requires a continuous and intelligent approach.

Industrial workers operating breathing-safe equipment in a manufacturing plant, promoting workplace respiratory safety and compliance with health standards.

Photo of BreatheSafe and Stairway inspecting the installation of an OnGuard system on a Tunnel Boring Machine.

How OnGuard Keeps Operators Protected

To ensure the safety of operators, BreatheSafe’s OnGuard air quality manager continuously monitors and manages air quality inside control rooms, break rooms, medical rooms, and offices.

The system automatically detects changes in pressure, carbon dioxide (CO₂), and dust levels, then reacts intelligently to any changes in air quality. It maintains positive pressure inside the room to prevent contaminated air from entering and logs air quality data for compliance and performance tracking.

This fully automated process allows operators to focus on their tasks while OnGuard maintains a stable and safe working environment without the need for manual adjustment.

Photo of one of the OnGuard systems on a Tunnel Boring Machine.

Custom Solutions for Demanding Conditions

Not only the RoomSafe system, but BreatheSafe also provides tailored solutions for underground machines, as well as electrical enclosures. Each system is custom-designed to meet specific site conditions or equipment requirements, ensuring optimal performance, safety, and reliability.

Whether it is protecting operators underground, safeguarding electrical components from dust and heat, or maintaining clean air in break rooms, BreatheSafe delivers integrated air quality solutions that enhance both safety and operational efficiency across all environments.

Operator Cabins – BreatheSafe System

What it does:
BreatheSafe system filters and pressurises air in mobile machinery like excavators, dozers, trucks, and drills.

Key features:

HEPA H14 filtration removes 99.995% of harmful dust (carbon filter optional for gas removal)
HEPA Panel Return Air Filter scrubs and filters the internal air
Positive pressure keeps contaminants out
Real-time monitoring of CO₂, PM2.5, airflow, and cabin pressure

Why it matters:
It protects machine operators at the source of exposure and helps your site meet safety standards for air quality.

BreatheSafe system fitted to a Sandvik Loader 517i

Electrical Enclosures – VoltAire System

What it does:
VoltAire protects sensitive electronics inside the enclosure by preventing dust ingress and heat build-up. This improves the reliability and longevity of critical electrical components.

Key features:

EPA E11 pressurisers filter incoming air.
Positive pressure prevents contaminated air from entering.
Automatically manages pressure and flushes out hot air when electronics begin to overheat.

Why it matters:
Electrical components are highly sensitive to heat and airborne contaminants. Reducing maintenance costs and extending equipment lifespan.

High voltage electrical safety equipment in industrial setting, featuring yellow control panels with warning labels and black electrical components.

VoltAire system fitted to a Caterpillar 796AC HV Cabinet

Our Commitment to Zero Exposure

At BreatheSafe, our mission is clear: Eliminate operator exposure to airborne contaminants. With the integration of OnGuard, we are helping create safer underground environments where operators can work confidently and efficiently, knowing their health and well-being are protected.

High-visibility workwear for industrial safety with respiratory protection at manufacturing plant in Australia.

Keep Your Operators Safe Everywhere

Air quality is not negotiable in the workplace. Dust, CO₂, and poor ventilation can put workers at serious risk and compromise the reliability of your equipment.

Get a Quote

Saving Lives in the Smoke: A New Approach to Firefighter Safety

Aug 26, 2025

Technical

Aug 26, 2025

Firefighters battle more than flames; smoke filled with toxins poses an invisible, long-term threat to their health. In this interview, BreatheSafe’s General Manager of Engineering and Product, Tommi Perkins, shares how innovations are helping protect those on the frontline.

Learn more about the high-temperature solution

Q: Tommi, wildfire fighting is one of the most demanding jobs in the world. From BreatheSafe's perspective, what are the primary health challenges facing these professionals?

Tommi Perkins: Wildfire firefighters have an incredibly strenuous task, often working up to 24 hours straight in high-temperature and high-smoke conditions. For a long time, smoke from wood fires was presumed relatively safe, but research has proven this is not the case. The smoke contains a dangerous mix of gases and particulates, with studies identifying up to 31 carcinogens.

The challenge is that prolonged exposure to these fine particulates and gases, which is an industry given, causes significant and permanent lung damage. This can lead to cancers, COPD, and other serious respiratory illnesses. Many in the industry still believe they can't burden firefighters with PPE because of the risk of overheating in a high-intensity, remote environment, but modern medical research is now highlighting the massive damage being done to firefighters’ lungs.

While wearing heavy PPE in the field can be impractical, we can still protect firefighters by creating a clean and safe breathing environment inside the enclosures of their vehicles and heavy machinery, where many are either operating or taking a moment’s respite.

Q: So, how does BreatheSafe's general solution, used in mining and construction, translate to this unique environment?

Tommi Perkins: The approach is very similar. The solution is to protect the entire enclosure rather than just the person, and it’s a tried and tested method. We can isolate any enclosure from the outside air, like a dozer cab or a crew transport vehicle, by creating positive pressure inside. By delivering high volumes of purified, clean air into the space, the internal air is constantly pushed out. This ensures that none of the gases, dust, or ash from the outside environment can make its way into the enclosure.

The only way for air to get inside is through our filtration system. This creates a safe environment where firefighters can step in, take off their heavy gear, and cool down, confident that the air they are breathing is purified and safe.

Q: Firefighting poses some very specific risks that mining might not. What modifications or additions have you made to address the reality of flames, heat, and embers?

Tommi Perkins: You're right, the threat of flying embers is a key concern. Our solution for firefighting equipment, such as dozers that are literally pushing burning trees, includes a spark arrestor and a pre-cleaner to extinguish embers and remove heavy ash and soot before it reaches the air filter. We also use heat-resistant and flame-retardant filters to ensure that the system can withstand high-temperature air.

Another critical modification we’ve made addresses the issue of heat. The last thing you want to do is introduce 176°F (80°C) air straight into the cabin onto an already hot and uncomfortable crew. We have designed a system that mixes the incoming air with the machine’s already cooled air from the air conditioning system before it passes through multiple stages of filtration. This ensures the air introduced is safe to breathe and also helps the firefighter cool down, as well as continuously filtering the air inside the cabin. The process of mixing and cooling the incoming air before it is moved into the enclosure is actually part of a patent-pending system.

Q: What about the types of vehicles and machinery used in firefighting? Can you provide solutions for all of them?

Tommi Perkins: Yes, we can. We have designed systems for a wide range of vehicles, from frontline dozers and fire engines with huge cabs to emergency crew transports and even light support vehicles. While a lot of fire equipment has sufficient excess power for our systems, a key challenge is that these vehicles are not built with adequate sealing, unlike modern mining equipment.

The industry is also poorly addressed right now. I've seen some existing proposed solutions, which filter the air in the space immediately around them, like a home room purifier, which means they’re only targeting air already inside the cabin and not necessarily in the breathing zone of the crew. There is nothing right now that provides a comprehensive solution. Our unique approach of filtering all incoming air and then mixing it with the air inside the cabin is something no one else has done yet.

Wildfire smoke is a silent threat to firefighters’ health. BreatheSafe’s cabin protection systems provide clean, cooled air and a safe space to recover—so our frontline heroes can keep breathing safely.

Comparing Cabin Filtration Systems: What is the BEST?

Apr 7, 2025

Technical

Apr 7, 2025

In high-risk industrial environments such as mining, tunnelling, construction, and heavy machinery operation, airborne contaminants like respirable dust, diesel particulates, and chemical vapours pose serious threats to operator health and safety. In such conditions, cabin filtration systems must go far beyond the basic requirements of HVAC.

This article explores the three common cabin filtration system types: Open Circuit, Closed-Circuit Dual HEPA, and Closed-Circuit Tri HEPA. It explains why only Closed-Circuit systems should be considered for effective cabin protection.

What Makes a Cabin Filtration System Effective?

An efficient cabin air filtration system must achieve more than particle removal inside the cabin. It must function as an integrated system that delivers:

✅ HEPA filtration (≥99.95% efficiency at 0.3 microns) for both fresh and recirculated air

✅ Closed-Circuit air filtration, ensuring all cabin air, both incoming and recirculating, is filtered

✅ Positive pressure maintenance to prevent unfiltered air from entering

✅ Sealed integration with HVAC systems to ensure air quality and operator comfort are not compromised

These are not optional features—they are the foundation of compliance, operator health, and operational uptime.

1. Open Circuit Filtration - Not Recommended

An open circuit filtration system relies on the OEM HVAC filter for recirculating air inside the cabin, which usually features a low-grade cabin filter, not capable of removing fine respirable particles.

This creates a partial protection scenario, where fresh air is filtered to HEPA standard, but recirculated air is not. In dusty environments, this results in the accumulation of contaminants inside the cabin, compromising air quality over time.

The image shows the recirculated air filter from a dozer.

❌ Recirculated air bypasses the OEM filter

❌ Unfiltered internal dust builds up and re-enters the breathing zone

❌ Operator exposure increases with time, even if fresh air is clean

❌ Not compliant in high-risk or regulated environments

2. Closed-Circuit Dual HEPA Filtration

A closed circuit dual HEPA system filters both the incoming fresh air and the recirculated cabin air through independent HEPA filters. This creates a fully sealed, controlled environment where all air the operator breathes is continuously cleaned.

✅ HEPA filtration on all air pathways, fresh and recirculated air

✅ Dual HEPA stages improve system and filter longevity

✅ Maintains positive pressure to prevent ingress of contaminated air

✅ Continuously purifies internal air by scrubbing the cabin air

3. Closed-Circuit Tri HEPA Filtration

Tri HEPA systems take the closed-loop design further, using three stages of HEPA filtration to ensure maximum protection, longer filter life, and redundancy. Often paired with gas-phase filtration, CO₂ monitoring, and advanced sealing, these systems are built for critical-risk environments where safety is non-negotiable.

✅ Triple HEPA filtration layers reduce decay time

✅ Optimised filter loading, extends the recirculation filter's life

✅ Proven best for extreme dust working environments

Choosing the Right Cabin Filtration System

System Type	Fresh Air	Recirculated Air	Recommended for Air Filtration System?
Open Circuit	✅ Yes	❌ No (uses OEM low-grade filter)	❌ Not recommended for any condition
Closed-Circuit Dual HEPA	✅ Yes (HEPA H14)	✅ Yes (HEPA H13)	✅ Yes (for most conditions)
Closed-Circuit Tri HEPA	✅ Yes (HEPA H14)	✅ Yes (HEPA H13 & H14)	✅ Yes (for extreme conditions)

Final Thoughts

The effectiveness of a cabin filtration system is not just in what it filters—but in how completely it isolates and treats the air within the operator’s breathing space. Systems that filter only the incoming air while neglecting recirculated air are inherently flawed, especially in environments where fine particulate or toxic exposure is constant.

For any serious industrial application, Closed-Circuit HEPA filtration—dual or tri-stage—is not just recommended, it is essential. Don’t leave operator health and compliance up to chance. If your current setup still relies on Open Circuit design, it’s time to reassess.

BreatheSafe offers engineered solutions tailored to real-world conditions, ensuring that every breath your operator takes is as clean as possible.

Additional Resource

How BreatheSafe replaces OEM filters to deliver superior operator protection.

Meandu Trial HV Cabinet Dust Prevention

Oct 18, 2021

Komatsu 830E HV Field Trial

Ongoing trial of BreatheSafe Dust Mitigation for a QLD Coal Mine

In November 2020, BreatheSafe consulted Meandu Mine of Stanwell Corporation concerning airborne mine dust in their high voltage cabinets. A High Pressure HEPA Filtration system was specifically designed and installed on a Komatsu 830E HV cabinet with four TL pressurisers.

Last Updated: 26/10/2021

Overview

The HV Cabinets are designed to use the unfiltered air from the alternator fan to cool the heat sinks on the inverters.

As the air is unfiltered the cabinets are prone to mine dust ingress requiring cleaning leading to potential mine dust exposure for maintenance staff.

Its our understanding that most site maintenance crews use compressed air to clean cabinets, which is a source of generating airborne dust inside the workshop area with potential risk for peak dust exposure for workers near the plant.

Aim

To develop an engineered solution to eliminate the requirement to clean the cabinets at all.

The Problem

Dust in the high voltage cabinet

Dust and health

Exposure to high concentrations of respirable dust will lead to the development of a range of serious irreversible lung diseases such as silicosis.

Issues with high and low voltage cabinets

Cabinets subject to unfiltered air introduced via the alternator fan to cool heat sinks.
Hazardous dust is forced though unsealed duct seams / deteriorated component gaskets into the main compartment requiring maintenance and cleaning.
Cleaning of these compartments typically occurs every 500 hours and presents risk of hazardous dust exposure to workers.

Dust and electronics

There are several good reasons to keep dust off and out of electrical components.

Cooling – if a component is covered by dust its core temp will slowly rise due to the dust acting as an insulator.
Some components are not as sealed as we would like so conductive materials can settle on/in the components leading to failure.
A lot of dust can become corrosive when moisture is present so if we keep the dust off & out of the component the you will not get the corrosion.
By maintaining pressure in the compartment, we are reducing the amount of moisture being forced through it by the cooling system.
Less wiring connector damage both by the dust & by the service team having to force the plugs apart as fine dust is locking them together reducing.
The aim is to ensure that we are safely circulating enough cleaned fresh air through electrical enclosures to keep the clean side duct free and cool.
Improve machine up time as they will not have to be stood down for cleaning.
We believe that if the cabinets are kept clean you will get an improvement on the reliability of each component.

View Our Systems

The Solution

Engineering Control

We feel that the BreatheSafe solution should be ranked as the highest level of protection our engineering control has eliminated the requirement to clean the compartment using compressed air.

Dramatically reducing potential exposure to all personal in the area.
We recommend that the compartment is cleaned prior to installation of the system.
Note we will still have the requirement to change the filters.
We feel that PPE and RPPE when blowing out cabinets is not enough protection. It is the least reliable control measure.

BreatheSafe Design

High Pressure HEPA Filtration

Cabinets have been cleaned out prior to installation.
The Main HV cabinet has been fitted with 3 High Pressure TL unit.
Arc Shoe cabinet has 1 standalone High Pressure TL unit.
These systems are variable speed pressurisation and HEPA H14 filters.
Max pressure achieved with the engine off: 1200 Pa above ambient.
Auto pressure setpoint at 400 Pa above OEM engine-driven fan pressure.
TL units force air into HV cabinets creating positive pressure.

High Pressure Hepa Filtration units positively pressurise cabinet pushing against dust ingress from unsealed ducts, gaskets and door seals, preventing dust-laden air from entering the cabinet.

Click images to expand

Installation

Easy installation in one day
Everything provided for installation in the install kit
3 x 76mm & 20mm power supply aperture from top of the cabinet to accommodate pressurisers.
Controller mounted to top of centre access door – also pressurised through HEPA filtration.

3715 Hours BreatheSafe HV Cabinet Komatsu Pressuriser

The BreatheSafe High Pressure Filtration Unit is the only pressuriser on the market capable of producing the pressure required to maintain a dust-free cabinet.

BreatheSafe HV Cabinet Komatsu Pressuriser

The Result

The BreatheSafe variable speed high-pressure system is proving to significantly reduce/eliminate dust loading in the high voltage cabinet. One comment was that the cabinets are getting cleaner. As time goes by, we feel the dust in the cabinet will very slowly be forced out of the cabinet = so it will gradually get cleaner.

The system is 11 months in operation, and components, including serviceable filters, have withstood harsh weather and mining conditions whilst maintaining efficiency.

Achievements:

Cleaning with compressed air has ceased/worker exposure to mine dust diminished! The cabinet is maintaining a significantly reduced dust load. Internal temperature maintained relevant to ambient. Components/wiring easily visible for fault finding. Minimised static dust on components - Extended component life. Heavily reduced downtime for maintenance/repair costs. The system was installed in November 2020 and has done over 3715 hours of service. The system has been inspected at 1000, 1500, 2230 and 2800 hours and is still running the original filters. System capacity maintains a 57% load with no drop in sealing efficiency after 3715 hours. Max pressure test dropped 390 Pa to a total of 810 Pa– consistent with filter loading/truck voltage & door seals.

BHP Autonomous Cabinet Field Trial

Jul 26, 2021

Caterpillar 793F Autonomous Field Trial

BHP Trial

In 2018, BHP consulted with BreatheSafe concerning airborne mine dust mitigation for their Autonomous 793F trucks. A field trial was started to deliver a full system to mitigate airborne dust, heat and water ingress with their Caterpillar fleet of Autonomous Trucks - electrical cabinet.

The Problem

The ongoing issue is airborne mine dust: there is dust build-up inside the electrical cabinet. This is causing electrical systems to run hot due to dust accumulation and electrical connections to corrode and fail when contaminated with abrasive particles. Airborne mine dust can comprise different materials that affect components with abrasive and corrosive properties.

Also, temperature control issues are critical in enclosure design. When temperature increases, it will affect electrical components. The optimal temperature for most electrical equipment is between 40⁰C to 50⁰C. Thus, when the internal temperature of electrical components rises above the optimal range, then their lifespan will decline. Further complication is OEM electrical cabinet has a small opening door which makes servicing difficult and time consuming

Other Industry Issues

High-voltage electrical safety testing equipment in a workshop setting at BreatheSafe, with control panel, laptop, and safety gear on an industrial yellow testing station.

The Solution

BreatheSafe custom design insulated cabinet enclosure: equipped with HEPA fresh air pressurisation integrated with temperature sensing and active cooling plus large access door; the key features are:

Keeps electrical components dust free.
Dramatically reduced maintenance costs.
Active cooling maintains enclosure internal temperature below 50⁰C.
Automatic Pressure Control (positive pressure is always maintained).
Remote monitoring: ongoing data for temperature and positive pressure.
Long life brushless electrical motor.
HEPA filters mitigate dust particulate down to submicron level.
Large door makes easy access to internal components.
No tools required for all dust mitigation system servicing.
Full service back up

View Our Systems

The Result

BreatheSafe autonomous cabinet enclosure can effectively control airborne dust down to submicron level with active cooling program. As soon as temperature rises above 45⁰C then pressuriser motor goes into high speed to cool enclosure effectively maintaining below 50⁰C.

Remote monitoring data has assisted with maintenance schedule routine with real time data for dust loading calculation.

Auto pressure control maintains positive pressure inside enclosure regardless of wind speed or as vehicle moves forward. Engine air pre-cleaner ejects coarse dust to successfully extend HEPA filters lifecycle.

Trial success, BHP has placed order to convert fleet to BreatheSafe custom enclosure.

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