The Covid-19 pandemic and the disproportionate number of deaths among the elderly population of care homes in many regions worldwide, exposed very starkly the vulnerability of care home residents to cross-infection. On premises laundries (OPLs) have a significant role to play in addressing this.
They and need to be consistently providing clean linen which is assuredly free of pathogenic bacteria and viruses (including Covid-19). We look at the different means by which this can be achieved (and economically verified), using the latest techniques. Of equal importance is provision of the same justified assurance to hotel guests, that the towels, pillowcases and table napkins from their OPL do not carry unwanted micro-organisms to their hands and faces.
It is a startling fact that even in some regions, which pride themselves on their hygienic cleanliness, there is no legislative requirement for bug-free linen, either in care homes or hotels.
This is probably set to change and organisations that have not yet addressed this need to be preparing now.
Disinfection
For many years, the healthcare sector worldwide (and the laundries which serve it) practised implied thermal disinfection for hospital linen. However, this required processes which involved, for example, three minutes plus mixing time at 71C minimum or 65C for ten minutes. These generally achieved a 5log10 reduction in bacteria count, which met the demands of national healthcare legislation in most regions.
These processes may not be attractive to care homes, if their laundries utilise washer extractors with electric heating elements, because of the long warm-up times needed (although this can also be overcome using small, in-line, temperature-controlled, instantaneous gas-fired heaters – see LCN July/August 2020 issue).
Implied thermal disinfection may not be attractive to hotel laundries either, especially if these have no heating elements and rely on the hotel hot water system, which supplies the guest rooms (at temperatures below the thermal disinfection requirement). As a result, both the care home and the hotel sectors may be demonstrating wide variations in the quality of disinfection actually achieved, both from region to region and within any one region.
Different ways of ensuring adequate disinfection at low temperature are now readily available in virtually every region worldwide, with independent certification to assure their effectiveness. Some of these involve thermo-chemical disinfection at 50C or 60C, for example. Some can achieve assured disinfection at temperatures as low as 40C: in all cases it is vital to use the time-temperature-chemical combination specified by the supplier. Simply using a particular chemical or a particular temperature is not sufficient.
Many healthcare providers make use of the European Norm EN 14065, which describes a simple system for assuring the laundry user of the ongoing effectiveness of the disinfection regime. This system is now available for adoption by on-site laundries in both care homes and hotels, with economically viable controls to demonstrate disinfection quality to customers on an ongoing basis. It differs considerably from the traditional implied thermal disinfection principle, which is based on the feed forward concept that if the hot wash is maintained at the requisite temperature for the specified time, then you can assume that the bug kill will be adequate. This did not always work well, especially if the temperature controls were not properly calibrated, or the washer was overloaded. The recently updated standard uses the feedback principle. You can adopt whichever disinfection regime suits you best, but you must verify by simple, regular monitoring that it is achieving consistently the desired degree of disinfection.
Greying
Progressive greying of white linen often leads to negative comments from users, suspicious of the wash quality and the competence of the launderer! These comments are generally entirely justified, because long-term greying is caused by re-deposition from the wash liquor of soiling and staining which has been washed off and has then been attracted back onto the clean cloth. Greying is countered by incorporating in the detergent a suspending agent, which wraps around the groups of soiling molecules to prevent re-deposition, both physically and by neutralising the tiny attractive electrochemical charges involved. The best detergent mixes contain sufficient suspending power to achieve this. Eliminating greying caused by re-deposition also removes the risk of leaving nutrient on the fabric and consequent bug breeding.
Yellowing
Random yellowing of linen can be caused by inadequate rinsing: it results from failure to remove the alkali (part of the detergent system), leaving residues which then yellow with the heat in drying. It is cured by attention to the rinsing, using a chemical sour if necessary. More serious are the areas of yellowing which appear in soiled areas (such as where the head rubs in the centre of a pillowcase), caused by inadequate removal of the protein these areas contain. The residual protein yellows with the heat of drying, after which it becomes much more obvious and very difficult to remove. It is prevented by setting up the pre-wash correctly (ensuring at least 4 minutes below 40C) and if necessary, by incorporating a small dose of emulsifier in the detergent mix.
Stain removal
Care home and hotel OPLs should always design wash processes to achieve complete removal of protein soiling and staining. This comes from human body fluids and many foodstuffs. Proteins must be adequately softened in a cool pre-wash (below 40C), before total removal in the main wash by good detergency and mechanical action. They will come away very easily if they are softened correctly, but if the temperature rises above 40C they will start to set (just like the white of an egg sets in a frying pan) and lock on to the yarns and fibres. Temperatures slightly higher than 40C may be offset with increased alkalinity after the set-up, by and under the monitoring of, a reputable detergent supplier. If protein stains become set they are then virtually impossible to remove, even in a good main wash. They can be removed by chemically burning them off with sodium hypochlorite and/or high alkalinity washes, but this could be accompanied by much reduced textile life, leading to expensive replacements.
Vegetable dye stains from tea, coffee, red wine and beetroot for example, can be easily removed with an oxidising agent, either in the wash or the first rinse, provided the protein stains are first removed correctly, as described in the previous paragraph.
Odours
The residual protein in yellowed areas or in greyed fabric can act as an effective nutrient for bug growth in the linen cupboard. The excrement from this bug growth can smell unpleasant and is a common cause of odour complaints. This problem can become much greater if the rinse water is not bug-free. Infected rinse water can arise if the water source for the laundry is from a river or stream which passes through an area of animal grazing. It can also become infected if it is accessible in storage by birds or rodents: a secure cover over any water storage tankage is needed to prevent contamination with urine, faeces or decomposing bodies of rats, birds or squirrels, for example.
Harshness
Once the care home or hotel OPL has sorted out disinfection, greying, yellowing and odours, the next most common complaint might be the harshness of fabric which comes into contact with the user’s skin. This is rarely a problem with table napkins, but it is not uncommon for guest room towels and robes be so harsh against the skin as to generate user complaints.
Harshness of a terry towel is often caused by over-drying, sometimes combined with incorrect dryer operation and set-up. Harshness problems arise if the drying air temperature is not optimised and if the endpoint for the drying cycle is not tuned properly. Curing harshness will usually result in towels which also stay white for much longer, often right through their useful life. Incorrect drying is a major cause of towel greying.
The best dryers have automatic cycle terminators fitted as standard, which leave a defined amount of moisture in the towelling and then tum themselves off. These usually work by infra-red detection of the correct residual moisture in the drying towel, but these sensors must be cleaned on a regular basis to work correctly.
The extra investment is usually returned within 12 months by the saving in heat energy, but the benefits of user delight at the softness and whiteness, and the usefulness of the extra drying capacity they create in the laundry, can frequently outweigh the financial attraction.
Conclusion
Getting disinfection established and independently verified is long overdue in some care home and hotel OPLs. Now at last there are economically viable processes and methods available. It is strongly recommended that anyone who is operating a laundry, where disinfection is critical to the finished quality, obtains a copy of BS EN 14065 (Textiles: Laundry Processes Textiles: Biocontamination Control System and follows the easy to read (and understand) advice that it contains. If you have any questions, then please contact the Editor of LCN and we will do our best to help.
The advice in this issue of Material Solutions is designed to offer a route to a step improvement in all aspects of wash quality, which if followed will enable you to both surprise and delight your customers.
- If you have problem that you think LTC Worldwide can help with, or that you feel would make a good subject for Material Solutions, please call T: 00 44 (0) 816545
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