Safe and effective floor drainage
Peter Jennings, Technical Director for ACO Building Drainage, explains the importance of good sanitary drainage in hospitals, and highlights the latest technology making wetrooms and shower areas safer for patients and more cost effective for hospital managers.
Ensuring sanitary drainage installations for hospitals are both effective and safe can present significant challenges for specifiers as there is typically a demanding set of criteria to be addressed. In addition to meeting the requirements for hydraulic capacity and water management, a system should provide easy access for those with limited mobility, safety features such as slip-resistant surfaces and fire protection, watertight connection to the surrounding floor, ease of installation and maintenance, and long service life. As drainage is an integral element of any hospital wetroom or shower area, choosing the right system is vital to the success of any new installation or refurbishment project.
The first fundamental aspect to consider is the hydraulic capacity of the drainage gully or channel system, which must exceed the maximum flow rate from the bathing area to prevent an excessive build up of waste water. This is not generally an issue for single shower head installations, but could be a serious issue if multiple shower heads are installed, particularly if pumped showers are used. In the latter case, larger channel-based installations are generally more appropriate as they can accommodate this higher level of waste water easily. It is important to consider the type of foul air trap used and take into account potential accumulation of hair deposits, as these factors can adversely affect the flow of water through the system.
As most shower installations provide bathing for single patients with varying degrees of mobility, it is necessary to provide facilities which allow the patient to shower in a safe, spacious environment that can accommodate a wheelchair if required. Patients’ privacy and well-being should be considered throughout the design and installation process. Many of the latest wetroom channels have been designed specifically for use in hospitals, care homes and lifetime homes, where a practical and safe drainage system is needed.
For example, ACO Building Drainage has developed an ‘Intercept’ channel configuration manufactured entirely from stainless steel with sloping inverts to the corner outlet foul air trap. The system effectively surrounds the bathing area, and together with an optional pumped waste option, ensures a drainage capacity of up to 24 litres per minute, keeping the floor free of excess water and therefore safer for patients.
The safety of both patients and carers can be increased further by the use of textured gratings, which provide a slip-resistant surface similar to flexible vinyl sheet flooring, exceeding SRV36 in wet conditions in compliance with British Standards (BS 7976 Parts 1 - 3 : 2002). Gratings are supplied with locks for security and overlapping longitudinal waterway inlet slots to prevent over-wash of water from the bathing area.
These latest Intercept channels are specifically designed for use with flexible sheet flooring and incorporate a mechanical vinyl clamp arrangement that ensures a 100% watertight interface. This clamp system allows the surrounding floor to be re-furbished as and when required without the need to modify the channel installation, keeping costs down for hospital managers.
Contrary to the popular placement of drainage in the shower area corner, the new Intercept channels are installed diagonally opposite the corner, essentially creating a barrier to water flowing toward the channel that would otherwise enter the general bathroom area. Falls towards the channel are created by using a rapid set levelling compound. There are two main advantages to this arrangement: firstly, a fall is not required towards the corner (practically such falls are difficult to achieve, especially if pooling of water is to be avoided outside the shower area), and secondly, in refurbishment situations, creating a fall requires either modification to the floor supporting structure or for the whole room floor to be raised; however, the Intercept channel is installed with only the immediate floor behind it being raised rather than lowered, considerably reducing the complexity and cost of installation.
These stainless steel systems provide durability and long life, as well as having low environmental impact. For example, ACO’s system is manufactured from at least 70% recycled stainless steel and is 100% recyclable once its working life is complete. The systems can be cleaned easily with soapy water and a clean water rinse, making them easy to maintain and eliminating the need for potentially hazardous chemicals.
As the ACO system features a maximum overall depth of 40mm, plus the foul air trap, it can be installed with minimal disruption to the existing solid concrete or timber floor. In certain specific drainage applications, it may also be necessary to provide drainage gullies that prevent the passage of smoke and fire and block off the oxygen supply in the event of a fire. A range of gullies are now available that conform to British and European standards for easy compliance with regulations and peace of mind.
In any hospital wetroom or shower area, patient comfort and safety should drive the design of the drainage system. With specially developed intercept channels and accessories now available, specifiers can find the right solution for their project, keeping the area safe at the same time as minimising costs.