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Air quality relies on compliance

For a safe and healthy building, maintaining ongoing ductwork compliance with TR/19 is essential, and will be a legal requirement throughout a ventilation system’s lifetime, as Gary Nicholls, Managing Director of Swiftclean Building Services, and co-author of TR/19, explains.

In order to maintain a healthy indoor environment with good air quality, you need a well-designed, clean, TR/19 compliant ventilation system. The leading industry guidance document concerning ventilation hygiene is TR/19 (Second Edition) Internal Cleanliness of Ventilation Systems, which is issued by the Building & Engineering Services Association (BESA). Following this guidance also ensures that you stay compliant with British Standard and European Norm BSEN:15780 and BG49/2013, BSRIA’s guide on Commissioning Air Systems.

All ductwork needs to be cleaned, and the accumulated dirt in it completely removed, at regular intervals. The frequency of those cleaning intervals will vary, according to the purpose and usage of each of the ventilation systems. The system in each part of a property must be classified under TR/19 as high, medium or low. For example, in a hospital, operating theatres and laboratories which require a particularly clean environment will require a high classification and more frequent inspection and cleaning as necessary. Wards, offices and visitor areas will require a medium classification and slightly less frequent inspection and cleaning as necessary than the high classification areas. Less populated areas such as boiler rooms or workshops can be given a low classification and will need attention the least often.

Kitchen extract systems must also be TR/19 compliant. Cooking even the healthiest food causes airborne fat, oil and grease which, as the exhaust air stream cools, solidify, forming deposits on the inside of the kitchen extract ductwork. These pose a serious fire risk. The thickness of these deposits must be controlled to ensure that average thickness does not exceed 200 microns – approximately half the thickness of an average business card. To ensure this control, the grease must be completely removed on a regular basis.

TR/19 contains very helpful tables which indicate how frequently the system must be cleaned, depending initially on how often and for how many hours each kitchen is used and once historical grease accumulation rates are established frequencies should be adjusted to keep within TR/19 defined limits. In a stadium or shopping centre, there may be different catering concessions with widely varying patterns of usage. It is important, therefore, to have a management system in place to control grease levels adequately in each kitchen extract system.

A clean mechanical ventilation system is more efficient and therefore takes less energy to run, so TR/19 compliance can reduce your energy costs. Insurance companies expect that you will comply with industry best practice in managing your property, so it may compromise your buildings insurance if you don’t comply with TR/19 and provide robust evidence of your compliance.

You must have before and after photography to demonstrate that your system has been regularly, competently and effectively cleaned to make it TR/19 compliant. If the worst were to happen, a fire can spread through your kitchen extract system to other parts of the building.

If negligence is proved in the event of a fire, and you haven’t maintained TR/19 compliance, the responsible person could face criminal charges and a potential custodial sentence; so evidence of your compliance will be vital.

In order to achieve TR/19 compliance, the system must be fully accessible. A new system must be tested and where necessary fully cleaned and commissioned before being handed over and put into use, but it does not currently have to include the full remit of access hatches or aids to access that TR/19 requires for ongoing compliance. In some instances, we find permanent features such as walls, ceilings and even staircases obstructing the ductwork, preventing access. Where we find inaccessible areas of a system, we can often retrofit additional access hatches to allow TR/19 cleaning to be carried out.

You will need expert help and guidance from a specialist provider to achieve and maintain TR/19 compliance.