Darren Ling explains why regular monitoring and maintenance of ductwork and ventilation systems in buildings are crucial to protecting the respiratory health of their occupants.
Occupational exposures to fumes, dusts and chemicals together account for around 4000 deaths a year,1 while some 38,000 individuals suffer breathing or lung problems that they believe are caused by their work.2 Asthma, bronchitis, allergic rhinitis, emphysema and mesothelioma are just some of the serious – and, in some cases, fatal – conditions that can develop as a result of exposure to respiratory hazards.
But such hazards are not just a concern in industrial workplaces; dusts, fumes and pathogens can build up in any situation where they are left unchecked. Dirty ventilation systems can seriously affect staff well-being and working environments, and legislation and best-practice guidelines clearly put the onus for cleaning maintenance on building owners, landlords and managing agents.3,4,5 Adopting an ‘out of sight, out of mind’ mentality when it comes to the air we breathe and the hidden-away systems that control and contribute to it isn’t an option.
Even in so-called “low-risk” indoor workplaces, like shops, offices, and schools, these contaminants are present. Ventilation systems provide the perfect breeding ground so it is vital to keep heating, ventilation and air-conditioning (HVAC) ductwork systems clean to avoid the accumulation of dust, dirt and potentially harmful bacteria.
For example, MRSA and Clostridium difficile are constantly in the news these days but they are not exclusive to medical environments, and are not only spread through touch. Both bacteria have been found in duct systems, blowing around the building and spreading far and wide.
Gases can also be present in indoor working environments. Ozone, for example, is commonly found where photocopying takes place. There is an occupational exposure limit (OEL) for ozone, as it can irritate the eyes and upper respiratory tract. An excess of carbon dioxide can cause people to feel lethargic and suffer headaches. Typically, it builds up as a result of poor airflow around a building, which can be caused by a ventilation system that is blocked by dust and dirt either on the incoming air side or the extract side. Again, the solution is simple: regular testing, surveying and cleaning.5
Poorly maintained extract ductwork also poses a very real fire risk. Within a ventilation system, there are fire dampers – shutters built into the system as fire containment measures. Heat and smoke travelling down the system will trigger a mechanical stop to release the shutter and prevent the fire spreading; if these shutters are clogged with dirt, dust and grease, they may not work properly.
It is therefore essential to check these systems regularly as part of a fire maintenance regime. The Regulatory Reform (Fire Safety) Order 2005 states that all fire dampers should be tested at regular intervals not exceeding two years, spring-operated fire dampers should be tested annually, and fire dampers in dust-laden and similar atmospheres should be tested more frequently. It also puts the duty of care on the building owner to minimise the fire risks by maintaining the ductwork properly.
A growing problem
And it is not just the pipework in a building that can cause problems – the condition of the premises can also be a factor. Take this example of an employee in an office, who suffered from asthma. His condition deteriorated and eventually became so severe that he had to be signed off work.
Upon investigation, it was discovered that rainwater had leaked into the building over a prolonged period and this, combined with shabby housekeeping of the premises, led to extensive growth of mould. Three types of organisms were found in abundance: cladosporium, stachybotrys and rhyzopus. Cladosporium can cause infections of the skin and nails, as well as sinusitis and pulmonary infections. Stachybotrys can cause cold and flu-like symptoms, including sore throats and headaches. But the most worrying is rhyzopus, which can cause fungal infections and can even be fatal to humans.
The unsanitary working conditions in this case arose primarily because routine building maintenance and housekeeping were not carried out by the duty-holder. The building’s leaky roof contributed to the apparent damp and mould growth and, while repairing it will help prevent the damp getting any worse, fixing the damage caused by mould growth will be a considerably bigger and more costly job.
The cost of ignorance
If the risks of illness, fire and death are not motivation enough, there are also possible financial repercussions. Failing to maintain any system is not cost-effective in the long run. Build-up of harmful deposits in ventilation systems can impair their performance, thus making them more expensive to run. The aforementioned health effects on employees will also likely result in a loss of productivity due to under-performance and sickness absence.
As regular maintenance and cleaning of extraction systems are usually conditions of insurance policies, insurers can and will refuse to pay claims in cases where contamination, or a fire, was due to lack of maintenance of ductwork.
Summary
In the current economic climate, building-owners and duty-holders must not be tempted to try to save money by neglecting their ductwork and ventilation systems. As clearly outlined in industry guidance,5 carrying out regular inspections and recommissioning at intervals no greater than 14 months will satisfy the regulator and insurance companies that the right steps have been taken to properly clean extraction and ventilation systems so as to minimise the risks to employees’ respiratory health, and guard against fire.
References
1 www.hse.gov.uk/statistics/causdis/ copd/index.htm
2 www.hse.gov.uk/statistics/causdis/ asthma/index.htm
3 HSE (2000): General ventilation in the workplace: Guidance for employers (HSG202), HSE Books, ISBN 0 7176 1793 9
4 Regulation 5 of The Workplace (Health, Safety and Welfare) Regulations 1992 states that mechanical ventilation systems, including air-conditioning systems, should be regularly cleaned, tested and maintained to ensure that they are kept free from contaminants
5 See The Heating and Ventilating Contractors’ Association’s (HVCA) Guide to Good Practice – Internal Cleanliness of Ventilation Systems TR/19 – www.hvcapublications.co.uk
Darren Ling is a director of System Hygienics.
Approaches to managing the risks associated Musculoskeletal disorders
In this episode of the Safety & Health Podcast, we hear from Matt Birtles, Principal Ergonomics Consultant at HSE’s Science and Research Centre, about the different approaches to managing the risks associated with Musculoskeletal disorders.
Matt, an ergonomics and human factors expert, shares his thoughts on why MSDs are important, the various prevalent rates across the UK, what you can do within your own organisation and the Risk Management process surrounding MSD’s.
