There are certain scenarios that increase the importance of the choices made when designing ventilation systems. In healthcare – where the careful specification of all building services is crucial of course – indoor air quality (IAQ) is an issue which has a direct impact on what matters most: the welfare of the patients.
Ventilation, literally, is the provision of fresh air into a space. The problem is, the word fresh is not always entirely accurate. The air might flow throughout every room of the building, and in a hospital or care home, patients and occupants are vulnerable and at a high risk of contamination and infection.
Prevention is protection – protection of the patients themselves, which in turn protects the provider from liability.
Assessing the risks
Digesting these outlines is easier said than done, but being aware of the responsibility building services providers have in these situations is simple.
Healthcare premises are bound by the duty of care. Poor indoor air quality can foreseeably be a cause of harm, so this potential must be eradicated through carefully considered system design.
Each room should be isolated from airborne threats. The spread of viruses is unpredictable but the consequences can be severe. Great care is taken in sterilising and disinfecting the equipment, objects, and indeed the people within these buildings – the cleanliness of the air should be treated with similarly scrupulous attention.
Isolating and eradicating contaminant airborne risks is one thing, but the constant battle against excessive CO² levels must be constantly monitored too. Relying on windows and draughts is not sufficient as during the cold winter months it is the natural reaction to try and keep the warmth in. As a result, CO² builds up to unacceptable levels, to the detriment of occupants’ health.
The advantages of excellent indoor air quality don’t stop there either. The work that nurses, doctors and carers do requires intense levels of concentration and attentiveness. It has been proven in schools and other public establishments that IAQ has a huge bearing on concentration, so inadequate levels must not be allowed to hinder their capability to perform such important work.
Natural vs Mechanical
Natural ventilation is established in the design of the building: making envelopes or openings in the building itself whereby air can be channelled. If the complexities of ventilation requirements in healthcare buildings are considered in the initial design, natural ventilation is indeed a viable option. But that is not to say it is the most suitable solution for safeguarding potentially vulnerable occupants.
The most pertinent issue with it is the lack of both isolation and regulation. Air flow is difficult to manage in the absence of a mechanically supplied negative pressure, which increases the risk of contaminating adjacent rooms and corridors. It is also heavily dependent on there being natural forces available. In cold weather for example, windows and vents might be shut and air will become stagnant as a result.
When the air flow and room temperature need such careful monitoring, the control that mechanical ventilation offers – or even a hybrid system – makes it a sensible choice.
Technological advances now mean that mechanical ventilation systems can be integrated and controlled within a heating system. Through one system, operators can ensure that each room is at a suitable temperature whilst maintaining a steady flow of fresh, clean air. The air is pulled into the room mechanically, is passed over the heat exchanger in the radiator, which displaces stale air and pushes it upwards towards a linked extraction fan which pulls air through at the same rate as the air intake.
The elevated importance of the indoor environment can be a burden – mechanical systems can help alleviate any health risks in the most efficient manner.
Energy costs better controlled
A mechanical, demand controlled ventilation system soothes this sticky financial issue perfectly. If the intake of fresh air is regulated, it reduces energy wastage caused by over ventilation or overheating.
A healthy environment for occupants that improves the provider’s bottom line.