Hotels, nursing homes, schools and similar businesses have many valid reasons for choosing an on premise laundry rather than a contracted out service. They may not have a commercial laundry service in their area or have had a bad experience with a local service. This could be because of high numbers of lost/damaged items, poor or inconvenient delivery service, charges for stock loss or minimum rates.

The housekeeper may want an OPL to control the service and believes it will reduce losses. An in-house service can run with a lower par stock and this minimises the initial linen set-up cost.

Organisations that are committed to washing guests’/residents’ personal clothing may feel it will be convenient to wash the linen and towels as well. Managers want to have more control over results in terms of whiteness and stain removal.

However, the case for taking laundry in-house can rarely be made on grounds of cost reduction. A well managed and properly equipped commercial laundry should produce a minimum of 100pieces per operator hour (ppoh) and leading laundries now top 200ppoh for flatwork, with the correct training.

In contrast, an OPL rarely achieves more than 20 – 40ppoh. In nursing homes and school laundries the work will be mainly clothing so in these cases, the rate could be compared with a workwear laundry with an output of around 60ppoh.

Labour is by far the largest cost in any laundry, often 25 – 30% of the total. So in a hotel laundry paying £6.50 per hour, each piece will cost up to 32.5p in labour while in a commercial laundry the cost will be 6.5p per piece. Small on-premise laundries will also find that costs for water supply and effluent, energy and chemicals are significantly higher than for the large commercial laundry. For example, efficient commercial laundries will use tunnel washers with a typical water consumption of 6litres per kilogram of work and this may be reduced to as little as 2litres.

On-premise laundries using washer-extractors may consume around 25litres and as a result pay more in water and effluent charges. Commercial laundries are often better equipped for handling large bulky items such as duvets, which take a long time to dry, and for handling high volumes of flatwork.

So looking purely at costs the best choice for an organisation with high volumes of flatwork, might be to wash personal clothing in-house to minimise losses and provide a quick turnround while using a commercial laundry for linen to benefit from the economies of scale.

However, despite the cost arguments many organisations still want to process all laundry in-house for the reasons given. Such laundries can produce good output and high quality as long as they design the operation correctly and make sure that they work to maximise their efficiency.

Hygiene control will be a priority, although it may be an area that is not always given the attention it needs.

In most instances the on-premise laundry washers will have a number of pre-set programs already installed in the machine’s PLC or on-board computer. The choice should include one program that achieves at least 71C for 3minutes plus machine mixing time. This program is used to comply with implied thermal disinfection in accordance with UK Department of Health guidelines (see HSG(95)18).

The process is essential for preventing infection outbreaks caused by linen carrying bugs from one resident or guest to all staff and customers in the establishment.

The program selection will also provide a lower temperature wash for delicate items such as personal clothing.

Train the staff

Laundry staff must be trained to use the right program for each load and this is particularly important with regard to disinfection. An OPL’s washers will usually have internal electrical heating elements. The time taken for these to raise the wash temperature up to 71C can extend the cycle time to 90 minutes or more.

This can be offset by using hot water fill or by installing a gas-fired hot water heater, but either option increases the capital costs and maintenance requirements. If neither hot water fills or a gas-fired water heater are available many operators are understandably tempted to select faster processes operating at much lower temperatures.

They may add extra detergent in an attempt to compensate and the wash quality may still appear satisfactory. However, washing contaminated work at temperatures as low as 40C does not kill the bugs and as these build up and breed, the stench of their excrement creates (at best) odours of stale cabbage and (at worst) powerful sewer smells.

One quick sniff in a care home on-premise laundry is all it takes to gauge the level of disinfection being achieved. The only case where low temperatures are acceptable for such work is where the laundry has installed a system for ozone disinfection.

CSCI, the body that regulates care and nursing homes, recognises ozone systems as an alternative to thermal disinfection. Sometimes, even where there is good provision for hot washing at thermal disinfection temperatures, human nature will still prevail and operators, particularly if not well trained, may use the shortest wash for every load.

This is understandable, especially when linen stocks are low and the laundry is always under time pressure. However, the consequences can be disastrous. The mistakes may only be discovered during an investigation into an outbreak of E.coli or Clostridium difficile. In the worst cases such outbreaks can cause several deaths and the negligence becomes a serious and costly problem.

Laundries must monitor their operation to make sure disinfection programs are used wherever necessary. Correct machine loading for good soil and stain removal and disinfection requires trained personnel, who know how much a washer can safely take and how to weigh the load.

There are two key requirements. First, the laundry must have accurate scales with current calibration and correct tare functions so that the weight of a basket of dirty washing is corrected for the weight of the basket.

If the laundry does not have the correct scales, operators will either guess the weight or, more commonly, resort to cramming as much into the washing machine as they can before closing the door. They work on the principle that the textiles might not get much of a wash, but at least they all get wet.

The second requirement is that the laundry managers should know how much should be loaded into the washing machine.

Avoid overloading

Most in-house launderers rely upon the washing machine manufacturer to tell them the capacity so if they are told the machine takes 23kg, they will do their best to get the full weight into the washing machine. If staff then find that the washed work is not clean or still has stains, they blame the detergent supplier.

Such practices can also mean that even when the correct disinfection program is chosen, the middle of load is not disinfected correctly.

Laundry managers and supervisors must realise that an overloaded machine will produce unsatisfactory results because it cannot deliver the degree of mechanical action needed for good soil removal.

Whatever the load, rubbing the soiled surface while it is wet and using a cleansing agent (soap or detergent) is absolutely essential.

If you reduce the mechanical action, then the soil removal levels are also reduced in proportion. The inside of the washing machine rotating perforated basket is fitted with “lifters” so that the wet textiles can be lifted out of the water inside the machine and then dropped back across the cage diameter to cause a “lift and squeeze” pounding action.

If the washing machine is overloaded, there will be no room to lift and squeeze the linen, so little, if any, of the soiling will be removed.

Check the loading

Supervisors should look at the washers while they are in use. If the load is simply rotating as a solid lump and the same items can be seen continuously rubbing against the door glass, the machine has probably been seriously overloaded. So, what is the correct amount of soiled work that should be loaded into a washing machine?

In the 1950s, the British Launderers Research Association (BLRA) studied this in detail. BLRA found that the load ratio (in grams of washing per litre of cage capacity) for any washing machine is dictated by the diameter of the perforated inner basket.

The larger the perforated basket diameter, the greater the lift and drop and therefore the greater the mechanical action achieved and the greater the loading ratio for the soiled items processed in the washing machine.

As a general guide, if the washing machine has an inner basket diameter of less than 100cm then the degree of loading for medium-soiled 100% cotton textiles should be 56g per litre of cage capacity.

For washing machinery with a cage diameter greater than 100cm but less than 200cm, the degree of loading should be approximately 72g/litre.

Consider fabric and degree of soiling

BLRA also noted that the amount that can be loaded varies with the type of item, the type of fabric and the degree of soiling.

It would not be physically possible to load the same weight of bulky items such as duvets or woollen blankets into a washing machine as you could if the load consisted only of 100% cotton pillowcases.

When processing heavily-soiled loads of work or polyester/cotton blends, the amount loaded into the washing machine should be up to 20% less than for light-medium soiled 100% cotton loads. This will also help to minimise creasing of polyester cotton work.

An on-premise laundry can produce good output and first-rate quality but to do so it is necessary to design the laundry carefully and to install correctly specified equipment to deliver the desired quality, minimise cross-infection and maximise the production. This must be achieved without overloading and without using inappropriate wash cycles.

An in-house laundry may need to install special water heating or make special provision for disinfection. It will need to train staff properly, even if they only work for a few hours per week.