Professional Laundry: Re-Washing & Identifying Common Problems
One of our key suppliers, RP Adam Ltd (Arpal Group) offers advice for on premise laundries focussing on at operational efficiency, re-wash rates, common problems and solutions.
Every laundry has the ability to reduce operating costs, energy use, improve operating efficiency and results. The starting point is an understanding of the total operational costs per kg of laundry.
To establish the quantity of linen processed, digital scales are used to physically weigh the washed/dried linen. From this, an accurate average of weight processed per week can be calculated. Everything else in the laundry revolves around this information including laundry procedures, staff hours, the size of machinery required, and ultimately the production costs per kilo of processed linen.
The cost per kilo of clean linen includes all costs within the laundry including utilities, labour, the depreciation of machinery, replacement of linen, chemicals and other sundry costs. When these production costs are itemised, the laundry manager then has a benchmark to compare costs and efficiency with other similar laundries. For example, a laundry washing large amounts of restaurant linen will have a higher operating cost per kg due to the heavy duty programs required compared to a laundry washing mostly bed sheets and towels.
Is Your Laundry Production Capability Correctly Scaled?
Undersized washer extractors lead to higher laundry costs because it results in laundry staff:
- Working longer hours to get the washing done.
- Taking shortcuts so they can finish within the hours allotted.
- Tending to put a lot of the washing through on short cycles.
- Skipping critical wash programmes such as pre-wash or rinse, or shortening the wash time.
It is also important to get the right ratio of tumble dryers to washer extractors because working with undersized dryers can cause bottlenecks in a laundry.
Are Your Re-Wash Rates Acceptable?
Every laundry manager’s dream is to achieve 100% clean results every wash. In the real world this is highly unlikely and the target therefore is to keep rewash rates as low as possible.
Remember the five basic factors that contribute to clean linen?
- Chemical action.
- Mechanical action.
Deficiencies in any of these factors can lead to higher reject rates. For example, contact time in various cycles of the wash formula are important, as are sufficient pre-flushes to help reduce water soluble soils and sufficient post-rinses to remove residual soils and chemicals from linen. Failures in any part of the process are likely to lead to higher re-washes.
Average re-wash rates per business type include:
- Hospitality: 2-5%.
- Nursing Homes: 6-8%.
- Hospitals: 4-10% (due to a wide range of variables).
Whereas hotels may experience a 2-5% re-wash rate predominantly due to human error, in care homes the percentage is slightly higher at around 6-8% and this is normally due to:
- Washing machines used in care homes are usually smaller than those found in large hotel laundries.
- Staff wash more varied wash loads.
- Care homes use more varied wash temperatures (from 30°C to 90°C, whereas hotels usually wash most at +60°C).
- Under time pressures, operatives may select the wrong wash programmes to speed up the overall wash process.
Every laundry should implement a strict classification procedure so that only very soiled linen is washed in a heavy duty wash programme. Proper classification of linen is important as are dependable relationships with your laundry equipment/chemical suppliers who will assist in ensuring wash standards are being met.
BEWARE: Re-wash levels lower than 1%
This may seem highly efficient but also may indicate excessive use of detergents and a reliance on hot wash (heavy soiling) programmes. The resulting “cost” to the business will be the cost of replacement linen caused by above average linen damage.
BEWARE: Re-wash levels higher than accepted levels
Obviously this is unacceptable and may be an indication of poor linen classification or inappropriate washing procedures, both of which may lead to discoloured or unclean linen and increased labour time to remove staining.
Common Problem 1: Yellowing (or Galling) of White Fabrics
This yellowing effect is caused by residual alkali left on the fabrics which have not been rinsed out properly at the end of the wash cycle (more common when a detergent booster is used in conjunction with the main detergent). When this is not properly rinsed, it may cause a chemical reaction between the residues in the cloth and the heat of the dryer. It can also be caused if chlorine bleach residues are left as a result of carry-over from the first rinse of a wash cycle. To prevent yellowing, a laundry sour chemical can be used to neutralise the residual alkalinity. Sours are normally colourless with an acidic odour and, if required, are dosed in the last rinse cycle.
Common Problem 2: Greying of White Fabrics
This is usually caused by insufficient/low concentrations of detergent in the main wash cycle. Too little detergent will not adequately suspend the soiling and it can re-deposit back on to the washed fabric. Greying can also be caused by over drying or it can incrementally build up in hard water conditions if the water is not sufficiently softened (which eventually leads to the fabrics being washed out, requiring replacement). NB: Greying on poly-cottons cannot be rectified as the surface will be physically damaged – this is why most poly-cottons are non-white/pastels).
Common Problem 3: Fraying
Normally caused by either 1) chemical damage through use of excessive bleaching or 2) using a low temperature pre-wash followed by an intense hot main wash programme. Any over bleaching will cause progressive rotting of fabric which will need to be replaced. NEVER USE CHLORINE BLEACH IN THE HOT WASH as this seriously damages fabrics. Remember, protein staining must be washed out of fabrics and not bleached out.
Common Problem 4: Rust Stains
Rust spots on clothing usually come from rust/iron deposits breaking loose in water pipes or water heaters and finding themselves in the washing machine. Rust staining can also occur from iron deposits in water e.g., following droughts, when the water levels are low, sediments can accumulate within pipes and affect the water supply. Rust cannot be washed out normally and can only be removed by special chemical treatments using either a Hydrofluoric acid or an Oxalic acid solution. These are hazardous chemicals and extreme care must be taken to ensure fabrics are properly re-washed to remove any residual chemical.
Common Problem 5: Mould & Mildew Stains
Mildew can attach to cotton, linen, silk and wool fibres as well as synthetic fibres. It effectively eats natural fibres, damaging and weakening the fabric, and leaves unsightly stains. The most common cause of mildew growth is damp laundry being left/stored too long before it is washed. To remove mould and mildew, the fabric should firstly be vigorously shaken or brushed outdoors to prevent its spread within the laundry area. Remove as much of the powdery substance as possible being sure to brush both sides of the fabric. Remember that mildew spores can be harmful and should not be inhaled, so a face mask is essential.
Pre-treat the stains if possible with a liquid detergent. Allow to work for at least 30 minutes. Then launder the fabric in the hottest water suitable for the material. Chlorine type bleach can be used on white 100% cottons to help restore whiteness. Oxygenated bleaches can be used on coloured fabrics or man-made white fibres (polyester, acrylic, nylon) to remove the stains.
Completely submerge the items and allow them to soak for at least eight hours. Check the stain and if it is gone, wash as usual. If it remains, mix a fresh solution and repeat. It may take several soakings to remove the stain but it should eventually be removed.
A 10 Step Guide to Stain Removal
The following 10 simple guidelines will help you address staining problems.
1. Treat the stain as promptly as possible – do not delay.
2. If you are using a specialist destaining fluid, follow the instructions for use religiously – do not experiment.
3. Test first in an inconspicuous spot to check for colour fastness before you go too far.
4. Apply stain treatment to the back of the stain as the goal is to remove the stain from the clothing. If it is a large stain on a larger item soak in suitable pre-wash container such as a sink or plastic bucket.
5. Be wary of the effects of bleaching agents as bleaching one stained spot may result in uneven colour removal and ruin the entire garment.
6. Do not mix stain removal products as they can cause toxic odours and cause damage to fabrics/clothing.
7. Wash stain treated items a soon as possible after treatment.
8. Be careful when using any dry cleaning solvents. Ensure they are rinsed out thoroughly, and air dried. Never put dry cleaning solvents directly into the washing machine.
9. Be patient! Stain removal can take time and may sometimes require repeated treatments.
10. Some stains cannot be removed without damaging the clothing or its colour so be aware of what is/isn’t possible.