The commercial washing machine has undergone a gradual evolution. Most of the changes are under the skin, so they are not obvious, but the result is a far more reliable and flexible tool.
The first major change was the introduction of the high-spin washer- extractor which offered a more energy efficient alternative to the rigid-drum type.
Although cheaper to manufacture, rigid-drum machines are more labour intensive with the laundry process usually involving a separate hydro-extractor to further reduce residual moisture content for drying. This combination not only occupies more space in the laundry but can also cause potential installation problems.
Energy forces
The energy forces exerted on both washing machine and hydro-extractor necessitate securing with foundation bolt fixings, the energy transmitted being absorbed by the building structure. This can cause major headaches (quite literally) in buildings with suspended floor construction. The problem is alleviated by the suspended-drum alternative.
The suds container features a more sophisticated support system, enabling the drum to float freely and therefore rotate faster, with the energy forces being absorbed by dampers.
Hydraulic oil-filled dampers are more effective than friction dampers but in both cases, substantial anchor fixing is not needed except when the machine is plinth mounted. This broadened customer choice by putting any capacity model into one of two camps. If the OPL was processing large quantities of towels, then the installation of a high-spin machine would save large amounts of money. If, however, it was processing easy-care linen then the benefits of a high-spin washer-extractor with its greater capital cost would be questionable.
Deciding what machine best suits customer needs is best achieved in consultation with a recognised supplier or manufacturer of commercial laundry equipment, one who will survey the property correctly and calculate accurately what equipment will most effectively and efficiently process the given amount of laundry, with regard to time, space and staffing.
Calculations need to be specific, taking account of machine load and application-related criteria.
In a hotel, these would include the number of beds and the occupancy rate; type of bedlinen, restaurant linen and kitchen accessories; and additional demands from, for example, function suites and pool or sauna.
Healthcare establishments have specific requirements which must be assessed and can greatly influence machine quantities and capacities. In addition to the number of beds and residents, the percentage of incontinence must be taken into account. This has a significant impact on the quantity of laundry produced and influences the type of machine that can process it. The laundry must also be properly planned in order to avoid the risk of cross infection. Advice on the handling of soiled laundry in healthcare applications is given in the publication NHS Executive Guideline HSG(95)18.
It also covers recommendations concerning wash programs. Anyone involved in the purchase of machines which are to be used for sluice and thermal disinfection work should ensure that the specification conforms with this. The thermal disinfection temperatures recommended are either 710 C for 3minutes or 650 C for 10minutes. Recent research in hospitals has indicated that this is inadequate as some forms of bacteria are not destroyed at these temperatures. There have been cases of re-infection even when the recommendations have been followed. As a result, the CSC (Central Sterilising Club) has set up a working party to investigate and is likely to propose an increase in the disinfection temperature.
Other factors that should be taken into account are the installation requirements of the Water Supply (Water Fittings) Regulations 1999. The backflow section of the regulations seeks to avoid the possibility of mains water contamination and define the risk factor and accepted protection device for the five fluid categories listed.
Risk level
Washing machines in healthcare premises are defined as high-risk, category 5 but because of regional variance in interpretation of the regulations, this risk level could be applied to any commercial washing machine.
The highest level of protection against backflow is a Type A air-gap and certainly any mains-connected washer-extractor in healthcare establishments should feature this. If a Type A air-gap is not included, the installation should have an approved breaktank fitted. Most manufacturers are now offering machines that provide some sort of air gap, but it is worthwhile to establish what level is covered and whether the machine has been tested and approved by the WRAS (Water Regulations Advisory Scheme).
The wash function results from the interaction of four elements: time, temperature, chemical action and mechanical action. Changing one element will directly affect another; for example, increasing chemical input can reduce the need for mechanical action. Mechanical timers provided little opportunity for customising the wash program. Program card operation increased flexibility but was not entirely reliable and not user-friendly.
The introduction of electronics together with the development of new motor technology opened up a whole new area of washer-extractor development.
The ability to control and precisely vary drum rhythm, dwell time, dip level and other parameters through the electronic programmer interfacing with the frequency-modulated drive motor allowed new wash technology for niche markets.
This led to wash programs which could take advantage of advancements in chemical and cleaning technology.
Cleaning agents can be precisely and accurately dosed to process, for example, multi-structured garments like protective clothing. Other OPL applications include bedding programs, where wash parameters can be varied to compensate for different pillow fillings, and curtain washing. Other benefits include programs for water recycling where rinse water is discharged and stored in a tank for re-use, reducing running costs considerably.
If fitted with a compatible electronic control,the washer can be continuously updated to keep in line with technological developments without further capital investments. New wash programs or enhancements can be quickly downloaded from a laptop computer via an optical connector. This electronic data highway can flow in both directions to capture information concerning the washer extractor operation.
Validation is a key requirement in clean rooms where barrier machines process a variety of sensitive workwear. In the healthcare industry the batch monitoring of some equipment is essential in order to avoid the risk of cross infection. A number of process documentation packages are now available. Data capture can even extend to cover water quality.
Thirty-one
Systems such as Miele Watch extend this data flow to allow up to 31 machines installed on the same site to be monitored remotely from a single interface control box connected to a phone line. When a machine fails, fault codes are automatically fed back to the service centre. This is particularly useful for operators who have large numbers of machines on various sites, enabling nationwide monitoring from one central location.
Maybe one should sit and contemplate all these machine developments in Liverpool’s Caledonia Pub where the enterprising landlord has installed a coin-op launderette so that regulars can enjoy a drink while doing their washing. If that is the future of OPL washer-extractors, then make mine a pint!
