A Glossary of Terms for Smoke Shaft Testing

Smoke shaft systems are critical to fire safety in high-rise buildings and a key part of a smoke control system; therefore, the shaft’s airtightness is paramount. However, different terminology can confuse the average person preparing for air testing of their smoke shaft.

To clarify some common air-testing and smoke-shaft terms, we’ve assembled this glossary of words that can be difficult to understand in the field of air-testing smoke shafts. It includes terms related to air testing, smoke shafts, and test parameters. While it’s far from exhaustive, we hope it provides some guidance.

Smoke Shaft Air Testing – A glossary of terms A to Z

Here’s an A-to-Z glossary of terms related to air testing for smoke shafts:

A – Airflow Rate: The volume of air moving through the smoke shaft per unit of time, typically measured in cubic meters per hour (m³/h). Most smoke shafts need to achieve an airtightness target of 3.8 m³/h/m².

B – Building Regulations: Legal standards that govern the design, construction, and performance of buildings and smoke shafts, including fire safety measures.

C – Calibration: The process of verifying the accuracy of testing equipment against known standards. Smoke shaft air-testing equipment should be UKAS-calibrated

D – Damper: A device installed within ductwork or smoke shafts to control airflow.

E – Extraction Rate: The rate at which smoke is removed from a space by ventilation systems.

F – Fan Pressurisation Test: A diagnostic method used to determine a building’s airtightness by using a blower door fan to pressurise or depressurise the building.

G – Gauge Pressure: The pressure within a smoke shaft relative to the external atmospheric pressure, usually shown in Pascals (Pa).

H – Human toxicity: The impact of toxic substances emitted into the environment on human health, such as very leaky smoke shafts that emit smoke into the protected atmosphere.

I – Infiltration: The unintentional or accidental introduction of outside air into a smoke shaft, typically through air leakage paths such as cracks and openings within the envelope of the shaft.

J – Joint Sealing: The application of sealant at junctions, seams, or gaps to prevent air leakage in smoke shafts.

K – Kilopascal (kPa): A unit of pressure. 1 kPa equals 1,000 pascals (Pa).

L – Leakage Path: Routes through which air can enter or escape from a building or smoke shaft.

M – Mechanical Ventilation: The use of mechanical systems to control the indoor air quality by diluting and displacing indoor pollutants such as smoke or dust.

N – Negative Pressure: A condition where the air pressure inside the smoke shaft or building is lower than the air pressure outside. Some smoke shaft air tests use negative pressure to find air leakage.

O – Opening (AOV) Doors: Doors that open in each protected area, such as a stairwell landing, in the event of a fire.

P – Pressurisation Method: A technique used in air tightness testing where the building or smoke shaft is pressurised to a known level and the airflow required to maintain that pressure is measured. Readings are usually taken between 25 and 70 in 5Pa increments.

Q – Qualitative Analysis: The assessment of a building’s air tightness based on observations rather than numerical measurements, often using smoke or thermal imaging.

R – Retardant: A substance or device used to slow down or stop the spread of fire or smoke, such as fire-board and intumescent paint.

S – Smoke Shaft: A vertical duct designed to extract smoke from a building in the event of a fire.

T – Thermal Imaging: The use of infrared cameras to detect temperature differences caused by air leakage. When used with a blower door, it’s an extremely powerful tool for identifying air leakage in smoke shafts.

U – Useful Space Heating: When the smoke shaft is heated to 6-8C higher than the surrounding building temperature, combined blower door and thermal imaging can be used to identify air leakage through the smoke shaft envelope.

W – Weather Sealing Strips: Materials used to seal gaps around doors to prevent air leakage.

X – Xenon Test: A method for detecting air leaks that uses xenon gas as a tracer in a pressurised space.

Y – Yield Point: The point at which a material or system begins to deform under stress, which could affect the smoke shaft’s airtightness.

Z – Zero Tolerance to Air Leakage: Because the smoke shaft must achieve a low air leakage figure to pass the air test, extra care is needed during the design and construction of the smoke shaft.

This glossary covers fundamental terms associated with air testing for smoke shafts. For more detailed information on smoke shaft regulations, contact APT Sound Testing to chat with our smoke shaft testing experts.

Need help with air testing your smoke shaft?

If you need help with air testing your smoke shaft, we can help. Our experienced air test engineers have over 10 years of smoke shaft testing experience, so we know how to help clients pass testing and achieve smoke shaft sign-off.

Our premium smoke shaft testing service includes:

• Smoke shaft survey visits by experienced consultants.
• We are a UKAS and ATTMA Level 2 air testing company.
• Smoke shaft air test certification.
• The latest high-powered fan equipment
• UKAS-calibrated blower door equipment.
• Diagnostic air leakage surveys using smoke & thermal imaging.
• Rapid 24-hour testing service

We offer leading design, consultancy, and compliance for every part of your project. IAPT aims to provide a friendly, professional, stress-free experience for all your smoke shaft air testing requirements.s

For more information on our smoke shaft air testing services for smoke shafts, please get in touch with Darrenen directly on 07775623464, or email us at info@airpressuretesting.net

Contact APT for your smoke shaft Air Test.

APT Sound Testing Ltd is one of the UK’s leading UKAS-accredited testing laboratories for smoke shaft air tightness testing. We combine air leakage testing, smoke visualisation surveys, and thermal imaging inspections to accurately diagnose leakage pathways and help clients achieve compliance first time. Our experienced engineers conduct smoke shaft testing on residential, commercial, high-rise, and mixed-use developments across the UK.

Smoke Shaft Air Tightness Testing • Smoke Shaft Leakage Detection • Thermal Imaging Surveys • UKAS Accredited Testing • Nationwide Coverage

APT Sound Testing Ltd
📞 07775623464
🌐 www.aptsoundtesting.co.uk
📧 info@aptsoundtesting.co.uk

Helping developers achieve compliant smoke ventilation systems through expert testing and leakage diagnostics.

Guide to Smoke Shaft Air Testing for High-Rise Developments 

APT Sound Testing’s team of ATTMA Level 2 engineers carries out smoke shaft air testing using UKAS-calibrated equipment, with all testing undertaken in accordance with the latest applicable standards and guidance, including ATTMA TSL Issue 1, CIBSE TM23:2022, BS EN 13829 and BS EN 12101-2:2017.

Read our guide to the latest smoke shaft air testing regulations and standards.

How Smoke Shaft Air Testing Works

To begin the test, our engineer installs a high-powered blower door fan into an opening within the smoke shaft, typically at mid-floor level. We then temporarily seal the top and bottom of the shaft, along with other intended openings such as extract points and ventilation grilles.

Once the shaft is prepared, the fan pressurises it so its air permeability can be measured under controlled conditions.

Finding Air Leaks in Smoke Shafts

Our air testing engineer will conduct a controlled test to establish the smoke shaft’s air-pressure permeability. Smoke shafts are generally designed to achieve an air leakage rate of less than 3.8 m³/hr/m² at 50 Pa, subject to the requirements applicable to the particular project.

If the smoke shaft or AOV installation does not meet the required air permeability, our engineers can use specialist smoke-testing equipment to help locate the source of air leakage.

We use a high-powered smoke generator while the shaft is under pressure. Escaping smoke can make otherwise difficult-to-see leakage paths much easier to identify, allowing remedial works to be targeted more effectively.

Where smoke use could be problematic, our engineers can also use high-resolution thermal imaging cameras to help identify air leakage. Combining air testing with thermal imaging provides a highly effective way to investigate failed smoke shaft tests.

Smoke Shaft Air Testing Checklist

Before smoke shaft testing can take place, construction of the shaft should be substantially complete. To ensure the test can be carried out correctly and in accordance with the relevant requirements, the following points should also be addressed:

• No temporary seals should be present on the shaft envelope. Temporary seals are generally only permitted for dampers, fans and linking ductwork.
• Fire-stopping and penetrations should be fully completed throughout the shaft.
• No construction work or operatives should be present within the shaft during testing.
• The shaft should be clear of debris, tools and construction materials.
• A suitable 240V power supply should be available.
• Small blow heaters should be available in the smoke shaft, where required.

Meeting these requirements before our engineer arrives can help avoid delays and ensure the test proceeds efficiently.

Accreditation and Technical Competence

APT Sound Testing is a UKAS-accredited ISO/IEC 17025 testing laboratory, specialising in on-site (field) air tightness testing for smoke shafts in commercial and large-scale buildings.

Our UKAS accreditation demonstrates that our testing, reporting and quality management processes meet recognised technical and procedural standards.

We are also an ATTMA Level 2 registered organisation, qualified to test Large, Complicated and High-Rise (LCHR) buildings, as well as phased and zonal handover projects. In addition, our ATTMA EA accreditation enables us to perform accurate, compliant envelope area calculations for complex commercial buildings.

With more than 20 years of specialist experience, our engineers have provided testing and consultancy services on some of the UK’s most prestigious and technically challenging developments, including Battersea Power Station and the Imperial War Museum London.

This combination of accredited competence, specialist technical knowledge, and extensive industry experience lets us provide reliable, repeatable, and fully compliant smoke shaft air testing across a wide range of commercial and high-rise developments.

Contact APT Sound Testing

A failed smoke shaft air test can result in costly delays and remedial work. An experienced, appropriately accredited testing laboratory can help identify potential issues early and give your project the best chance of passing its smoke shaft air test on the first attempt.

If smoke shaft testing is required for your development, contact our smoke shaft testing specialist, APT Sound Testing, on 07775 623464 – 01525 303905 or email info@aptsoundtesting.co.uk to discuss your requirements and arrange a test.

Smoke Shaft Air Testing: Why It Matters and How to Avoid a Failed Test

Smoke shafts are commonly installed in high-rise buildings as part of a fire-engineered smoke control strategy. They play an important role in helping to remove smoke from a building during a fire, allowing escape routes to remain as clear as possible.

Because the smoke shaft is such an important part of the overall smoke control system, air tightness is critical. A smoke shaft that is too leaky may not perform as intended, which is why air tightness testing is required before the system can be signed off.

What happens if a smoke shaft fails its air test?

The usual air tightness target for a smoke shaft is 3.8 m³/hr/m². If the shaft exceeds this limit, the leakage can affect the performance of the smoke control system.

A failed test can also cause delays to a project, as the smoke control system may not be able to receive final approval from the fire system contractor and/or Building Control until the issue has been resolved.

Fortunately, a failed test doesn’t necessarily mean extensive remedial work is required. The key is finding where the air is escaping.

Finding and fixing smoke shaft leaks

We have extensive experience testing smoke shafts of all sizes, from individual shafts through to large-scale developments.

When a smoke shaft fails its initial air test, we can provide a diagnostic leakage investigation to identify the cause of the failure. We use a combination of smoke testing and thermal imaging to locate air leakage paths within the smoke shaft envelope.

This approach allows us to pinpoint areas that require attention rather than relying on trial-and-error sealing.

Once the investigation is complete, we collate our findings into a detailed air leakage report. This gives the client a clear indication of where remedial sealing work is required, allowing contractors to focus their efforts on the areas that matter.

On previous projects, this targeted approach has enabled remedial works to be completed quickly, with the smoke shaft subsequently passing its air tightness test on the next visit.

Our smoke shaft testing service

Our smoke shaft air testing service includes:

• Smoke shaft survey visits carried out by experienced consultants
• UKAS and ATTMA Level 2 accredited air testing
• Smoke shaft air test certification
• High-powered fan equipment suitable for a range of shaft sizes
• UKAS-calibrated testing equipment
• Detailed leakage diagnostics using smoke machines and thermal imaging
• Rapid testing and reporting

Experienced smoke shaft air testing specialists

Air Pressure Testing is one of the few companies in the UK to hold both UKAS and ATTMA Level 2 accreditation for air tightness testing of buildings, as well as smoke shafts and floor plenums.

Whether you’re arranging a smoke shaft test for a new development or need help diagnosing a failed test, our team can provide both the testing and diagnostic support needed to identify problems and help get the shaft ready for a successful retest.

For more information about our smoke shaft (AOV) air testing services, or to request our smoke shaft checklist, please contact us through our website:

Air Pressure Testing – Smoke Shaft Air Testing

Elevate Fire Safety Standards with Professional Smoke Shaft Air Testing

Smoke shaft air testing is a critical component of modern fire safety strategies, helping to ensure that smoke control systems perform effectively when they are needed most. In the event of a fire, smoke presents one of the greatest risks to building occupants, accounting for more than 60% of fire-related fatalities through smoke inhalation.

Our premium smoke shaft testing service includes:

• Smoke shaft survey visits by experienced consultants
• We are a UKAS and ATTMA Level 2 accredited air testing company
• Smoke shaft air test certification to UKAS/ATTMA
• The latest high-powered fan equipment
• UKAS calibrated equipment.
• The best diagnostic leakage service using smoke machines & thermal imaging.
• Rapid testing service

At APT, we provide comprehensive smoke shaft air tightness testing and remediation services, helping developers, contractors, and building owners achieve regulatory compliance while safeguarding occupants and emergency responders.

Why Is Smoke Shaft Air Testing Important?

Smoke shafts are commonly incorporated into fire-engineered solutions for high-rise residential and commercial buildings. As a key element of a building’s smoke control system, the air tightness of the smoke shaft is essential to its performance.

During a fire, smoke shafts work alongside Automatic Opening Ventilation (AOV) systems to remove smoke from escape routes and common access areas. However, if the shaft is not sufficiently airtight, the effectiveness of the entire smoke control system can be compromised.

Most smoke shafts are required to achieve an air permeability target of approximately 3.8 m³/hr/m². Failure to meet this standard can prevent the smoke control system from being signed off by the fire system contractor or Building Control.

Expert Testing and Remediation Services

APT has extensive experience testing smoke shafts of all sizes across a wide range of developments. In addition to air tightness testing, we offer specialist diagnostic services for smoke shafts that fail initial testing.

Using a combination of:

• Smoke testing
• Thermal imaging surveys
• Air leakage diagnostics

we can quickly identify air leakage pathways within the smoke shaft envelope.

Our findings are compiled into a detailed air leakage report, enabling contractors to carry out targeted remedial sealing works. This focused approach reduces unnecessary disruption and significantly increases the likelihood of achieving a pass during subsequent testing.

Why Undertake Air Testing for Smoke Shafts?

1. Compliance with Legislation and Standards

All buildings incorporating smoke shafts should undergo air tightness testing to demonstrate compliance with relevant standards and fire safety requirements, including:

• BS 9991:2015 – Fire safety in the design, management and use of residential buildings
• BS 9999 – Fire safety in the design, management and use of buildings

Testing provides evidence that the smoke shaft performs as intended and supports Building Control approval.

2. Improved Fire Safety

Smoke is often more dangerous than flames during a fire emergency. Effective smoke control systems help to:

• Protect escape routes for occupants
• Improve visibility during evacuation
• Reduce exposure to toxic smoke
• Assist firefighters during rescue and firefighting operations

Air tightness testing helps ensure that smoke shafts can effectively remove smoke and maintain safe evacuation conditions.

3. Verification of System Performance

Before AOV systems can be commissioned, the smoke shaft must demonstrate adequate airtightness. Testing verifies that the shaft can operate efficiently and deliver the required smoke extraction performance during an emergency.

Building Regulations and Smoke Shaft Standards

Smoke shaft design and testing requirements continue to evolve alongside changes in UK fire safety legislation.

For residential developments, BS 9991:2015 provides detailed guidance on smoke control systems and the role of smoke shafts in maintaining safe means of escape. Compliance with these standards is increasingly important, particularly in higher-risk residential buildings.

Professional testing provides documented evidence that a smoke shaft meets the required performance criteria and supports the building approval process.

How Often Should a Smoke Shaft Be Air Tested?

The frequency of smoke shaft testing depends on several factors, including building type, maintenance schedules, insurance requirements, and regulatory obligations.

New Buildings and Major Refurbishments

Newly installed smoke shafts should always undergo initial air tightness testing before commissioning. This confirms compliance and verifies that the system will perform effectively during a fire emergency.

Ongoing Maintenance and Periodic Testing

Following initial certification, smoke shafts should be regularly inspected and retested to ensure ongoing performance. As a general guideline, annual testing every 12 months is recommended.

Regular testing helps identify:

• Deterioration of seals
• Damage to the shaft structure
• Unauthorised modifications
• Air leakage that could affect system performance

Proactive maintenance ensures continued compliance and reliability throughout the building’s lifecycle.

Why Choose APT for Smoke Shaft Air Testing?

APT has successfully undertaken smoke shaft and AOV testing across London and the South East on a number of prestigious projects, including:

• Battersea Power Station
• Imperial War Museum
• Claridge’s Hotel
• The Berkeley Hotel

As one of the few companies accredited for both building air tightness testing and specialist smoke shaft testing, we offer a level of expertise that sets us apart.

Our accreditations include:

• UKAS accreditation
• ATTMA Level 2 accreditation

Whether you require compliance testing, diagnostic investigations, or remediation support, our experienced team can help ensure your smoke shaft achieves the required performance standards.

Contact APT

For more information about our smoke shaft (AOV) testing services or to request a copy of our smoke shaft testing checklist, contact APT today by calling 01525 303905 and speak with one of our specialists.

Preparing Your Smoke Shaft for a Successful Air Test

Achieving a compliant air test for your smoke shaft is a critical step toward project sign-off, especially for systems designed for Automatic Opening Ventilation (AOV). With strict airtightness targets and challenging access conditions, careful planning and preparation are essential.

Here’s our practical roadmap to help you pass your smoke shaft air test first time.

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Know Your Airtightness Target

Smoke shafts serving AOV systems are typically required to achieve an airtightness level of less than 3.8 m³/h/m² @ 50 Pa.

This is a stringent standard, particularly when you consider the relatively small envelope area of smoke shafts compared to their internal volume. Even minor gaps or incomplete sealing can result in a failed test.

Understanding your target early allows you to plan construction and sealing strategies accordingly.

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Seal All Potential Leakage Paths

Smoke shafts are often constructed from a mix of materials. Each element must be carefully sealed to ensure compliance.

Concrete Casting

Concrete walls generally provide the most robust and airtight barrier.

Blockwork

High-density blocks perform well, provided mortar joints are continuous and free from gaps.

Stud Wall and Plasterboard

Particular attention is required here. Ensure:

• Full sealing between plasterboard panels
• Proper sealing at junctions with concrete elements
• No service penetrations left untreated

Penetrations and Openings

Any opening within the shaft wall must be sealed internally, including:

• Service penetrations
• AOV fans
• Louvres
• Shutters
• Floor grilles

Use appropriate sealing methods such as:

• Taping and jointing
• Fire stopping materials
• Mastic or expanding foam

All sealing should be completed from inside the smoke shaft to prevent hidden leakage paths.

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Timing of the Air Test

The timing of your air test is just as important as preparation.

The test should take place when:

• The smoke shaft is fully constructed and sealed
• AOV fans and louvres/shutters are not yet installed
• All AOV doors are shut
• The top of the shaft is temporarily sealed

Testing at the correct stage avoids unnecessary retesting and programme delays.

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The Smoke Shaft Air Test Method

Smoke shaft testing should be carried out by a UKAS-accredited, ATTMA-registered company using pressurisation in accordance with CIBSE TM23 methodology.

The process typically involves:

• Selecting the correctly sized blower door fan to fit within a shaft opening (ideally midway up the shaft)
• Installing the fan into a temporary board sealing one of the louvre or shutter openings
• Pressurising the shaft using a UKAS-calibrated blower door system

The test itself takes only a few minutes, although the total site time is usually around 3–4 hours.

The shaft is tested to confirm it achieves the required 3.8 m³/h/m² target.

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What If the Smoke Shaft Fails?

Due to restricted access, identifying leakage paths inside a smoke shaft requires specialist techniques.

Diagnostic Methods Include:

1. Smoke Testing
The shaft is pressurised and theatrical smoke is introduced using high-powered smoke machines. Escaping smoke highlights cracks and gaps.

2. Thermal Imaging Surveys
The shaft is heated and pressurised while thermal cameras detect areas of heat loss.

3. Multi-Level Spotters
Operatives positioned on multiple floors identify leakage points while the engineer controls the test equipment.

All findings should be documented in a formal air leakage report and reviewed with the client before leaving site.

If smoke testing is required, notify relevant parties—including the local fire brigade—and consider restricting access during and shortly after testing while smoke disperses.

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How APT Can Help You Pass Your Smoke Shaft Air Test

At APT Sound Testing, our engineers have over 10 years of specialist experience in smoke shaft testing. We understand the common failure points—and more importantly, how to prevent them.

Our premium smoke shaft testing service includes:

• Pre-test smoke shaft survey visits by experienced consultants
• Testing by a UKAS-accredited, ATTMA Level 2 air testing company
• Official UKAS smoke shaft air test certification
• The latest high-powered fan equipment
• Fully UKAS-calibrated testing systems
• Diagnostic leakage surveys using smoke machines and thermal imaging
• Rapid response and testing turnaround

We provide expert design advice, consultancy, and compliance support across your entire project, delivering a professional and stress-free experience from start to finish.

For more information about our smoke shaft air testing services, contact APT Sound Testing on 01525 303905 or email info@airpressuretesting.net.

Preparing Your Smoke Shaft for an Air Tightness Test

Elevate fire safety standards with comprehensive air tightness testing and remediation.
Accredited Air Pressure Testing (APT) solutions help you meet regulatory requirements, improve smoke control performance, and protect building occupants.

Ensuring the safety and compliance of smoke shafts is a critical component of any building’s fire safety strategy. Smoke shafts are designed to restrict the spread of smoke and heat during a fire, protecting escape routes and supporting effective evacuation.

To confirm they perform as intended, air tightness testing is essential. Proper preparation can significantly increase the likelihood of passing the test first time and avoiding costly remedial works.

Top 10 Ways to Prepare a Smoke Shaft for Air Tightness Testing

1. Consult Smoke Shaft Testing Experts Early
   Engage air tightness consultants who specialise in smoke shaft testing at an early stage. Their expertise can guide effective design decisions, detailing, and sealing strategies.
2. Set Clear Airtightness Targets
   Establish the required airtightness performance—typically less than 3.8 m³/h/m² @ 50 Pa. Be aware that some smoke shafts may require different targets, so always confirm the specification in advance.
3. Use Robust Construction Materials
   Construct the shaft using materials capable of forming an effective air barrier, such as in-situ concrete or high-density blockwork.
4. Seal Internal Finishes Thoroughly
   Treat the internal surface of the smoke shaft as the primary air seal line. Finishes should be smooth and fully sealed at all joints and junctions, particularly where steelwork or other elements penetrate the shaft.
5. Seal All Service Penetrations
   Ensure all service, structural, and cable penetrations through the shaft envelope are carefully sealed using appropriate fire- and air-rated products.
6. Seal Door Openings Effectively
   All access doors within the smoke shaft should be fully sealed using robust, heavy-duty sealing systems to prevent air leakage.
7. Seal AOV Door Frames
   The perimeter of Automatic Opening Vent (AOV) door frames must be fully mastic sealed to maintain continuity of the air barrier.
8. Seal the Base and Head of the Shaft
   Pay close attention to the base and head of the shaft, ensuring both are fully sealed prior to testing.
9. Use Calibrated Testing Equipment
   Testing should be carried out using a UKAS-calibrated blower door fan, capable of pressurising the smoke shaft and accurately measuring air leakage.
10. Address Any Test Failures Promptly
    If the smoke shaft does not achieve the required performance, diagnostic methods such as smoke testing and thermal imaging should be used to locate leakage paths and guide targeted remedial works.

By following these steps, you can ensure your smoke shaft is properly prepared for air tightness testing, improving compliance with current building regulations and enhancing overall fire safety.

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Why Choose APT for Smoke Shaft Air Tightness Testing?

APT has extensive experience supporting clients with smoke shaft testing across projects of all sizes. We also provide a dedicated diagnostic service for failed smoke shafts, using smoke testing and thermal imaging to accurately identify air leakage paths within the shaft envelope.

On many projects where smoke shafts initially failed, our engineers have rapidly located leakage points, enabling targeted remedial works and successful re-testing with minimal disruption.

Our UKAS-qualified and fully trained engineers are highly knowledgeable in current industry standards and testing methodologies. This expertise allows us to provide clear, actionable recommendations to improve the performance of your smoke shafts.

Air Pressure Testing is one of the few companies in the UK that is both UKAS-accredited and ATTMA Level 2 accredited for air tightness testing of buildings, smoke shafts, and floor plenums. This ensures all testing is carried out in line with regulatory requirements and recognised best practice, giving you complete confidence in the results.

Smoke Shaft Air Testing: Pass First Time

Smoke shafts play a crucial role in fire safety within high-rise buildings. As a key part of a building’s smoke control system, they’re designed to help manage smoke movement during a fire, keeping escape routes clearer for longer. Because of this vital function, the air-tightness of a smoke shaft isn’t optional—it’s essential.

Most smoke shafts must meet a strict air-tightness target (typically 3.8m³/hr/m²). If they fail to achieve this standard, it can compromise the performance of the entire smoke control system, leading to delays in sign-off from fire system contractors or Building Control.

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Experts in Smoke Shaft Testing & Diagnostics

With extensive experience across smoke shafts of all sizes, we’ve helped countless clients achieve compliant test results. If a shaft fails its initial test, our diagnostic service quickly locates leakage paths using a combination of:

• Smoke testing
• Thermal imaging

This approach allows us to pinpoint exactly where air is escaping. We compile these findings into a clear, detailed air leakage report so that targeted remedial sealing can be carried out efficiently. In most cases, clients achieve a successful pass on the follow-up test.

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Our Premium Smoke Shaft Testing Service Includes:

• Comprehensive smoke shaft survey visits by experienced consultants
• Testing carried out by a UKAS and ATTMA Level 2 accredited air testing company
• Official UKAS/ATTMA-compliant smoke shaft air test certification
• State-of-the-art, high-powered fan and UKAS-calibrated equipment
• Industry-leading diagnostic services using smoke machines and thermal imaging
• Fast, reliable turnaround with our rapid testing service

Air Pressure Testing is one of the few companies accredited to both UKAS and ATTMA Level 2 for air tightness testing of buildings, smoke shafts, and floor plenums.

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Works to the Smoke Shaft: 

Certain events may require additional testing:

• Alterations to the smoke shaft:If modifications are made to the fabric of the smoke shaft or adjacent areas, retesting is necessary.
• Fire Incidents:After a fire incident, smoke shafts should be inspected and tested to confirm their ongoing integrity.
• Building Occupancy Changes:If the building’s use changes significantly, retesting may be required, i.e. an office building to residentialConsult Local Authorities and Experts:Always consult with local fire safety authorities, building control officers, or fire engineers. They can provide specific guidance based on regional regulations and best practices.

Remember that maintaining properly functioning smoke shafts is essential for occupant safety during fires. Regular testing ensures their reliability and effectiveness in smoke extraction.

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Need Smoke Shaft (AOV) Testing or a Checklist?

If you’d like more information about our smoke shaft testing services, or want to download our smoke shaft checklist, contact us by calling 01525 303905 or visit our website at:
www.aptsoundtesting.co.uk

We’re here to help you achieve compliance quickly, efficiently, and with confidence.