Shopping Cart

0 item(s) - £0.00



Why do I need an extraction/filtration unit?

According to the HSE (Health & Safety Executive) and the CoSHH legislation, employers are required to control the exposure of their employees to substances that are potentially harmful. Most businesses use substances, or products that are mixtures of substances. Some processes create substances. These could cause harm to employees, contractors and other people.

Sometimes substances are easily recognised as harmful. Some common substances such as paint, bleach or dust from natural materials may also be harmful.

By using a BenchVent LEV unit you are taking steps to ensure that you protect yourself, your clients and staff and ensure a cleaner, healthier working environment.


What is LEV?

LEV stands for Local Exhaust Ventilation. These are units that are designed to remove dust and/or fumes away from the operator’s breathing zone and either return cleaned air (recirculatory units) back into the workplace or, removed the dirty air completely to the outside atmosphere (ducted units)


How do I choose the best LEV unit for my situation?

It is well know that every year, thousands of workers in Britain develop occupational diseases from breathing in certain dusts, fumes or other airborne contaminants at work. LEV systems are designed to ensure that the risk from these contaminants are reduced, however some employees rush out and buy the wrong type or have it incorrectly installed. Follow this link to a simple guide on how to choose the best LEV system for your requirements.


Is it best to have a filtration or extraction unit?

Extraction - Total removal of particulates and odours.

The total removal of particulates and odours can be achieved through the extraction of the potentially harmful air, away from the operator and filtering it prior to exhausting it through a length of flexi-duct, either to the external atmosphere through a window or through a wall or partitioning. The flexi-duct does not have to be fixed as in most custom extraction systems, it can be easily and effectively placed through and open window or door whilst in use; alternatively, the 100mm x 2m standard hose can be fixed via a domestic louvered wall ventilation grille. These systems are a must when the unit is to be used regularly, especially in a confined space and windows are available.

Filtration as an alternative

Filtration is ideal, where the area from which the contaminated air is to be removed, is not located conveniently for the use of extraction. BenchVent filters offer several stages of filtration before the filtered air is returned in to the work place. Firstly, initial cleaning of the air takes place by way of high dust holding capacity intake filters; these 3 stage filters stop ever decreasing molecules to typically 5 microns. The open structure of the first stage discourages surface loading and promotes depth filtration, ensuring a high dust holding capacity and reducing resistance to airflow. The denser backing filter and final scrim material provides finer filtration to 5 micron. NB: Spray particulate size varies from 10 to 20 microns.

For finer filtration then optional EPA filters remove particles from typically fine dusts, powders and solder smoke. These are 85% efficient to the MPPS (most penetrating particle size) This is around 0.1 micron. The next stage is provided by carbon filters. Carbon impregnated fibre filters give additional filtration alongside the initial Intake filters, the filtered air is then recirculated back into the workspace.

For high level removal of odour then wide spectrum High Efficiency Activated Carbon filters are used. In these, filtered particles which pass through the intake filters are adsorbed by the carbon molecules in the filters and are prevented from being recirculated back into the working environment.


Do you use washable filters?

Washable filters are great as grease filters in cooker hoods and kitchen situations. They also have limited use in some situations where “sticky” solutions are being used. We at BenchVent do not use, or recommend washable filters. The main reason being that they are only effective when cleaned regularly. In most situations where BenchVent air filtration and extraction cabinets are used, the.


What warranty is available?

With all* BenchVents own units, there is a lifetime warranty. This is activated by registering your purchase on our online registration page . This is subject to certain terms and conditions and is a return to base warranty. This means that it is your responsibility to get the unit back to us. We will assess the problem, repair if covered by the warranty and return the unit free of charge. If the problem is not covered, we will advise repair costs prior to carrying out the repair. The cost of returning the unit to you under these conditions will be included in the costs.

* Does not include BenchVent Beauty units or those units that are distributed by BenchVent for other manufacturers. In these cases a standard 1 year warranty applies.


How long do the filters last?

Particulate filter: In the case of the particulate filter the filter life is dependent on use. We would recommend that in most cases they should be changed at least every two months.

Carbon Filter: This is a time dependent as well as usage. This is because the carbon in the filter will adsorb moisture and other gases from the atmosphere even when the units are not being used. Our recommendation is that they should be changed every 6 months as a minimum..


When do I know that the filters need changing?

Particulate filter: At the moment, our units do not have airflow indicators. These will be installed in the near future. The best way to check is by way of a visual check – are the particles being taken into the filter; or by offering an A4 piece of paper close up to the filter. The paper should be drawn up to the filter in the last centimetre or so and should remain there un aided. If it drops off, the filter needs to be replaced.

Charcoal and Carbon filters: These filters need to be changed every 6 months regardless of use as they absorb moisture and other contaminants from the surrounding atmosphere on a daily basis. This is as a minimum. If the unit is in constant use they will need to be replaced more often.


How do I dispose of my dirty filters?

In most cases it should be possible to discard of the filters with the general waste. However in certain cases; such as Pharmaceutical and Lab use, the contaminants may be required to be disposed of as hazardous material. Therefore we always suggest that you consult your waste disposal policy and/or local council environment office to see if there are specific requirements in place.


Do I need to service the unit?

General ongoing service is down to filter changes at the required time.

However, health and safety law says you must assess the risks to your workers from hazardous substances – dusts, fumes, vapours, etc. - and decide what measures to use to protect their health.

If the measures you adopt include extraction systems (LEV) to remove the dusts, fumes, vapours etc. produced by your work processes or activities, then you must maintain the LEV in efficient working order so it continues to provide the necessary protection. You should also have a periodic thorough examination and test (at least every 14 months) and must keep this record for at least 5 years. In addition, you should have information on the installed LEV system to confirm it provides adequate protection, which should be kept for the life of the equipment.


What is the purpose of a thorough examination and test?

It is a check that your LEV is still working as effectively as originally intended and is helping to protect your employees’ health. To be able to tell if it is still working as it should, you should be able to provide the examiner with information about the intended or designed performance of your system e.g. hood type and position relative to the process, airflow and other measurements.

This information might be in the form of an initial appraisal or commissioning report, if one was carried out, or for simple ‘stand alone’ systems it could have been provided as standard operating data by the suppliers of extraction equipment. Alternatively, it might be found in recognised guidance (including that from HSE) on simple processes/systems. (For examples see If none of this is available, you could consider getting someone competent to advise you. BenchVent do offer a LEV test and inspection service. Please contact us for more details.



Registered in England: 03127859 VAT No: 664779479