Fume Hood Ventilation Testing, Servicing & Validation

What is Fume Cabinet testing?

A fume cabinet is a piece of equipment that’s primary function is to protect the operator from toxic fumes, gasses or particulates. There are two key types, ducted fume cabinets and recirculating (ductless) fume cabinets.

The principle is the same for both types: air is drawn from the front (open) side of the cabinet and either expelled from the building via ducting or made safe through filtration and returned to the room.

The fume cabinet is designed primarily to:

Protect the user from inhaling toxic emissions

Secondary functions of these devices may include protection from explosion, spillage, and other functions necessary for the work done in the equipment and cleanroom environment.

Owing to the critical nature of what it is being used for, performance testing is vital to confirm that the fume cabinet operates at a level that ensures the desired capture, control, and removal of the emissions.

The tests are covered by COSHH regulations for Local Exhaust Ventilation Systems.

If the cabinet is already in operation in the laboratory, it is recommended that it be tested under two operating conditions: when installed (commissioned) and after use. COSHH regulations state that local exhaust ventilation (LEV) equipment be tested every 14 months.

For the “commissioning” test, the fume cabinet is installed at the customer’s location and tested when it does not contain anything, but with the ventilation system balanced in the installation. The “after use” test is performed after the cabinet has been installed and used.

Here at Total Clean Air, helping our customers to keep their work environment safe and fulfil their legal obligations is exactly what we do. Our fume cabinet testing is carried out to conform to BS EN 14175 and BS 7989.

Each member of our team has gone through extensive training, which means that when choosing Total Clean Air, you are entrusting your LEV testing to the competent person, just as the law says you should.

To request more information, call 01737 924700 today to speak to one of our experts.

Total Clean Benefits

  • All Work Is Guaranteed
  • Full Manufacturer Warranty
  • ISO Accredited Validation
  • Operational Qualification
  • Performance Qualification
  • References Available

Ducted Fume Cabinet Testing

Ducted fume cabinets have externally placed fan units that are connected to the fume cabinet via ducting. Generally, these cabinets pull air out of their front opening, , in order to vent to a safe position on the roof of the building. This discharge point is typically three metres above the roof line and from here, hazardous fumes can be safely expelled into the atmosphere.

The Control of Substances Hazardous to Health in the 2005 Regulations require that LEVs be maintained in effective working order and that they are in good state through examination and testing.

To this end, fume cabinets, ducts and all the relevant extraction equipment must be examined and tested at least once in every 14 months.

The relevant records and testing and repairs need to be kept for at least five years and the label attached to the cabinet must indicate the date of the tests and other pertinent information. Fume cabinets found to be below the standard appropriate for the stated type of use must be removed from use until repair is completed.

Whether you need your fume cabinet commissioned to ensure that it delivers the level of safety you need, or you want to arrange for our expert engineers to test and service your equipment, Total Clean Air will always provide you with a professional, reliable , cost-effective and friendly service. For information on our ducted fume cabinet testing and maintenance, call 01737 924700 to speak to one of our experts today.

Total Clean Air – Testing & Validation Services

Contact us today and find out how we can best serve you on your next project.

Ductless Fume Cabinet Testing

The recirculating or ductless fume cabinets are self-contained units that remove contaminated air from the opening, pass it through the filtration system and discharge it back into the room. The type of filter used depends on the class of chemicals to be used, and the filters in these cabinets have a limited lifespan.

It is vital to ensure that the absorbency capacity limit of the filter is not exceeded, as this may result in hazardous substances being released back into the work environment.

Consideration should be given to whether such equipment can provide adequate, reliable control of the anticipated hazards, and whether resources and a safe work system are in place to ensure that the unit is monitored and maintained.

The main reason for the use of a fume cabinet is to provide the operator and other laboratory personnel with a safe working environment. It is therefore vital that this equipment is constantly tested to ensure that it operates at optimum performance and consistently meets the required standards.

A ductless fume cabinet should be tested by an accredited, competent person when it is first installed. It is also covered under COSHH and must be tested every 14 months.

Total Clean Air offers general inspection and testing of ductless cabinets in accordance with BS EN 14175 and BS 7989.

Book a test today. Call 01737 924700 to get started.

At Total Clean Air, we provide a range of specialised on-site test solutions, including HEPA filter integrity leak testing for biosafety cabinets, as part of your cleanroom certification. For more details or to book a test, call 01737924700 at your earliest convenience.

Inflow Air Velocities

The proper face velocity of the cabinet (the speed at which the air is drawn into the cabinet) is of importance for the safe and efficient operation of the fume cabinet. While too much face velocity can often lead to turbulence and limited containment, not enough velocity can also affect cabinet performance. It is generally recommended that the face velocity of the cabinet be between 0.3 m/s and 0.5 m/s, meaning 60 fpm to 100 fpm, however, it is important to check the front velocity recommendation with local safety regulations before using the fume cabinets.

It is also important to carry out regular tests to check the inflow velocity of air in the vapour cabinets.

The purpose of this test is to confirm that the average airflow velocity meets the specified recommendations for the relevant sash configuration.

Adequate face velocity is required but is not the only factor for achieving acceptable performance and should not be used as the sole performance indicator.

Total Clean Air can send a qualified professional to your location to test your cabinets using state-of-the-art airflow monitoring equipment.

Pressure Differentials

Many fume cabinets are equipped with static pressure indicators that measure the static pressure difference across the duct or between the laboratory and the exhaust duct of the fume cabinet. Some of these indicators are aneroid pressure gauges, such as magnehelics, which are installed on the front of the cabinet above the sash.

The gauge is a flow rate indicator with a scale that instead of reading in velocity, reads in pressure units. Differences in magnehelic reading are not linearly proportional to differences in face velocity; therefore, they should only be used as an index of the performance of the cabinet.

A difference of 20% and above in magnehelic reading from the previous recorded reading indicates that the flow rate in the duct may have changed significantly since the last test. If such a change is noticed or there is any other reason to suspect that the cabinet is not functioning properly, then it is important to seek expert assistance.

Total Clean Air are fume cabinet experts who offer applications and solutions to test and verify the slightest pressure differential in any type of fume cabinet. Get in touch to know more about this.

Total Clean Air – Testing & Validation Services

Contact us today and find out how we can best serve you on your next project.

HEPA Filter Integrity Leak Testing

HEPA filters or High Efficiency Particulate Air filters, have been used as filtering tools for more than 5 decades. The high level of efficiency of HEPA filters for smaller than micro-particle sizes makes them ideal for use in areas where contamination control and cleanroom conditions are critical.

A mandatory test for Class I and Class II Safety Cabinets, Laminar Flow Workstations and where HEPA filters are installed in filtered fume cabinets, is a DOP (Dispersed Oil Particulate) test, carried out under working conditions to confirm the integrity not only of the HEPA filter but also of the seals and housing. The aerosol is spread upstream of the filter and the downstream face and filter seals are checked for leakage using a calibrated photometer.

HEPA filter testing is important to verify that they are correctly installed without leakage caused by manufacturing defects or poor installation. HEPA filters can begin to leak after some time or when the filter is clogged. Regular inspection for integrity and pressure drops can significantly reduce the risk of leakage.

At Total Clean Air, we provide a range of specialised on-site test solutions, including HEPA filter integrity leak testing for fume cabinets, as part of your BS EN 14175 equipment certification.

For more information or to book a test, please call 01737 924700 as soon as possible.


Double HEPA Testing

The HEPA filter is a key component of the fume cabinet. A HEPA filter is a flexible, dry filter made of microfibers set in a thin layer of borosilicate that looks and feels like a piece of parchment.

The filters are designed to protect people from a wide range of particulates however, they do not last forever, and they can wear and tear, which poses a significant danger to the workplace and staff. However, a double HEPA filter can be used to increase performance. To ensure that the double HEPA filter is up to standard, the filter system must be tested both by the manufacturer and by a certified, competent person.

Testing a HEPA filter entails a visual inspection, as well as the attempt to pass particles of a certain size through the filter.

At Total Clean Air, we have experienced technicians who are experts in HEPA and ULPA filters and who can carry out the necessary checks in your double HEPA cabinet to ensure that it meets the required standards. Book a test today. Call 01737 924700.

Total Clean Air – Testing & Validation Services

Contact us today and find out how we can best serve you on your next project.

Ductwork Inspection and Testing

Fume cabinets’ ductwork is constructed mainly of material that can work well with the intended use of the fume cabinet.

The instructions on the materials needed for fume-cabinet ductwork can be found in the EN 14175 guidelines.

It is highly recommended that each fume cabinet should have a dedicated vent and a fan system.

Where these are shared between more than one enclosure, facilities must be in place to monitor the failure of any part of the system and to report that failure to any other part of the system likely to be affected.

Where systems are used that allow fumes from more than one enclosure to be combined, robust risk assessment and control measures must be put in place to avoid the concurrent use of mismatched substances.

All ducting is expected to come with leak-proof inspection covers that will allow for easy internal inspection during periodic maintenance and testing.

Total Clean Air are experts when it comes to ductwork inspection and testing. Our well-trained staff and state-of-the-art equipment will quickly detect problem areas, and we will come up with a hassle-free fix.


Leak Testing

A typical fume cabinet has a structure-like box with a sash window that is movable. Experimental procedures are performed within the cabinet, which is ventilated consistently and safely, usually through an extract blower and ductwork.

Chemical fumes are burnt and diluted over and over in the atmosphere and so have a negligible effect on human health. That said, at least annually, fume cabinets should be accredited after checking for leaks and to ensure that they are running safely.

Typical measures include measurements of the face velocity, checks for smoke and concentration of tracer gas. Tracer gas containment checks are particularly important, as studies have shown that face velocity is not a strong indicator of leakage in the fume cabinet.

The equipment to be used must be correctly calibrated and maintained before beginning any testing and the performance requirements for the fume cabinet to be tested, must be reviewed to ensure the appropriate ones are used.

Therefore, it is vital that you work with experts who know what they are doing when it comes to fume cabinet leak tests.

At Total Clean Air, we offer a wide range of services to meet the needs of our customers across the industry, providing a comprehensive validation document.

This will include the identification number of the fume cabinet, the date of the test, the type of test performed, the general room conditions at the time of the test, the results of our inspection and the performance test and any remedial actions needed.

Total Clean Air – Testing & Validation Services

Contact us today and find out how we can best serve you on your next project.

BS EN 14175 Testing

British Standards BS EN 14175 define the protection and performance criteria for fume cabinets for general use and further detail the technical specifications needed for fume cabinet design, manufacture, installation, and containment testing.

While past instructions have relied on face velocity measurements as a way of checking fume cabinet performance, current practise focuses on demonstrating containment, which is done most reliably by setting up a periodical programme for tracer gas containment testing.

The current BS EN 14175- 2:2003 describes all appropriate procedures for performance testing in detail.

At Total Clean Air, we offer a complete range of fume cabinet testing solutions, all designed and built to stringent BS EN 14175 standards.

To find out more about our solutions and services or simply make an inquiry, call 01737 924700 to speak with an expert at your earliest convenience.

Schools Fume Cabinet Testing

Schools and colleges are required by law to have their fume cabinets undergo a comprehensive test at least once every 14 months. At Total Clean Air we can carry out the required compliance tests on any fume cabinet make and model, whether ducted or filtered.

Our test procedures are also compliant with COSHH REG9, CLEAPSS G9, BS ENm14175 and other applicable school standards.

Choosing Total Clean Air means that you entrust a competent person with your fume cabinet test as required by legislation.

To ensure accurate test results, all our test equipment is regularly calibrated. If any operational fault is found, we can carry out remedial work as needed at the fume cabinet.

We have extensive experience in building, checking, and maintaining fume cabinets for schools – please contact us and we will be happy to help. Call 01737 924700 to book a test today.