Many of the problems seen in our laboratories have arisen as a result of poor process controls and management in the washroom area. These problems range from residual unknown stains to colour loss and fabric damage.

There are still many launderers that wait for something to go wrong and then end up not only upsetting a customer but also having to pay out often hundreds of pounds in compensation. In addition to losing the customer, they stand to lose their professional reputation.

One way of avoiding this type of problem is to regularly monitor what’s going on in the washroom.

This is where the routine use of test pieces becomes an invaluable launderers’ tool. Not only will the test piece confirm that the launderer is achieving the right levels of stain and soil removal but it will often highlight aspects of the wash process where costs of water, steam and chemicals usage are out of balance.

The results of the test piece can also be used as a marketing tool to provide a customer with the reassurance that not only is the laundry correctly processing their valuable textiles, but also causing the lowest levels of fabric damage so their stock lasts as long as possible.

The illustration shown here demonstrates the most common test pieces used to monitor the wash process.

They are (clockwise) protein soiling – blood, milk and carbon; mineral oil soiling; vegetable oils; vegetable dyes; and in the centre, unbleached cotton calico for assessing whiteness maintenance, brightness and fabric damage.

There are a whole range of artificially soiled test pieces available to test the efficiency of the laundry wash process for specific soils and stains – but these samples are the most popular test pieces for the healthcare and hospitality industry assessments.

They are designedso that they do not come totally clean in just one wash – and it is essential that when selecting the test pieces that they are all manufactured and evenly soiled with a constant type of soiling – otherwise the results achieved are like comparing apples with pears and have little value.

Always ensure that test pieces are from a reputable manufacturer and they have been stored and prepared correctly.

Wrong thread is faded by bleaching

A very up-market health resort and spa purchased a range of high quality bathrobes that were embroidered in gold coloured thread with the spa logo and name.
Within a couple of washes the dark gold colour of the embroidery had faded to a pale cream and was barely noticeable.
The spa management immediately blamed the laundry for excessive bleach usage, that not only damaged the embroidery but could also damage the bathrobe – although there was no evidence as yet of any additional damage
The launderer was adamant that hypochlorite bleach had not been used and the use of peroxide bleach could not have possibly caused the problem now seen.
Examination under ultraviolet lighting failed to identify the familiar dark rings associated with excessive use of bleach, and the OBA levels on the bathrobe were excellent. There was no bleach damage to this bathrobe.
By carefully un-picking a small portion of the logo and subjecting the small bits of thread to a burning test it was identified that the thread used was a standard viscose thread, which is difficult to dye so as to be colourfast to an oxidising bleach.
In this example, the embroiderer had simply used the incorrect thread and not the more expensive (but highly resistant to bleaching) polyester thread.
Solution: Replace the existing embroidery with the correct thread and ensure all future items have the embroidery thread specified.

Contamination turns white towels creamy yellow

A hotel purchased a large quantity of new white towels for use and then sub-contracted the towels out to a local laundry. The owners became rather upset when, within weeks, the towels started to take on a distinct ‘creamy-yellow’ hue as shown in the photograph.
The launderer was adamant that the towels were being rinsed correctly, and were not being over-dried. However, any suggestion that the problem might be caused by something the manufacturer had put on the towel was also wrong.
Laboratory testing showed the towel had a pH of 5, so the launderer had been souring rather heavily. When tests for residual iron (rust) were carried out, the familiar pink tint appeared confirming that the laundry has a problem with rust contamination.
The rust could be coming from a variety of sources – for example, from the water supply, from the steam or water lines and so on.
No matter where it was coming from however, the source had to be urgently identified otherwise the launderer could be facing a hefty claim for the premature replacement of these towels (and all the rest of his other customers’ textiles) due to the chemical damage that will occur – especially if he is using any bleach.
Solution: Seek external assistance to first identify the source of the iron/rust contamination, and then replace old pipework or treat the water supply as required.

Ultraviolet shows up chewing gum residue

The customer returned this 100% Egyptian cotton duvet cover to the laundry complaining of residual marks.
On close examination there were three distinct types of marks – two of which were readily identified as pinch-roller marks from the folder and old residual blood.
The third mark took the form of a ‘smear’ and made the material in the area quite stiff.
When examined at 15x and 60x magnification, a layer of a gelatinous material that had a very high fibrous and hair content was identified.
Under normal lighting the mark was a light brown/creamy coloured mark, but under ultraviolet the mark became a very dark ruddy/brown – indicating a high protein and possibly metallic content.
Closer examination revealed the mark was chewing gum residue which will not wash off the fabric during a normal wash process – and fortunately for the launderer, when the duvet cover was ironed, the chewing gum residue did not make contact with the ironer bed.
Solution: Although the chewing gum residue was now quite hard and crisp, caused by heat from the ironer, a gentle rub and soaking in solvent will soften the chewing gum and allow it to be removed safely.