Tooled-up for cleaning

Out of sight out of mind is very often the approach when it comes to maintaining the hygiene of ventilation ductwork, sometimes with dire consequences. So in response to the growing need for information on the management and maintenance of most ductwork systems, the industry's institutions have collaborated to produce a Ventilation Hygiene Toolkit.

The package contains publications from CIBSE, the HVCA, BSRIA and the Health and Safety Executive. These aim to provide a broad range of information and advice to satisfy current best practice requirements.

From the HVCA comes TR/17: Guide to Good Practice – Cleanliness of Ventilation Systems. This covers both new and existing ventilation systems, including ductwork, ahus, fan coils and all plant and ancillaries associated with air distribution systems. The guide sets out standards for testing, cleaning, and verification of internal cleanliness. The publication also includes an appendix on relevant legislation and guidance.

Guidance to the Standard Specification for Ventilation Hygiene from BSRIA targets facilities managers, who may have limited knowledge and experience of building services. The publication describes the process for conducting a ventilation hygiene contract. It also applies to the health and safety requirements of air conditioning and other mechanical ventilation systems, though it does not apply to local exhaust ventilation for process plants.

The guide aims to help engineers meet the new health and safety regulations, which require compulsory compliance with maintenance and cleaning practices. The competency of bidding cleaning companies can also be assessed and their recommendations understood. The guide can help users ensure that building insurance standards are attained, along with any hygiene checks for building environmental accreditation.

The HSE guide, General Ventilation in the Workplace – guidance for employers, is intended for employers and gives basic information on the benefits and limitations of effective general ventilation in the workplace.

It defines what is meant by general ventilation and gives information on fresh air requirements as well as the health implications of insufficient fresh air. The guide covers the principles of natural ventilation as well as looking at the use of general ventilation as a means of controlling exposure to substances hazardous to health as required under the Control of Substances Hazardous to Health Regulations (COSHH) 1991 and associated approved codes.

Also included are the current ventilation standards and advice to employers on how to achieve effective ventilation in the workplace. It outlines the methods used to assess the effectiveness of ventilation systems including maintenance of mechanical systems. A final section sets out the legal requirements for ensuring effective ventilation, and where to get further information and help.

CIBSE's contribution to the toolkit, TM26: 2000 Hygienic Maintenance of office ventilation ductwork, gives guidance for those managing mechanically ventilated and air conditioned buildings. Specifically it gives information on the issues of assessment and maintenance of the microbiological cleanliness of the ductwork system. The guide includes an appendix giving an overview of the current practice in designing and operating ductwork systems.

TM26 proposes protocols for obtaining microbial samples from the air in occupied spaces and from the inside surfaces of ducts. It also indicates the levels of microbial contamination that are likely to be found on uncleaned and cleaned duct surfaces, and gives advice on interpreting the results of sampling. The procedure may also be used following cleaning or disinfection to assess residual microbial contamination.

The Ventilation Hygiene Toolkit is priced £49.50 including postage for CIBSE, HVCA and BSRIA members, and £89.50 including postage to non-members. To order a copy contact CIBSE Publications Sales, tel: 020 8675 5211; fax: 020 8675 5449.