MATERIAL SOLUTIONS
best way of doing this is by occasional examination of a typical frontal area on one garment from a batch, using a good microscope, set up to focus on say an area 25mm x 25mm. Other techniques can be borrowed from cleanroom technology, using vacuum to remove fibres and particles from the surface of a test garment filtering this over a graticule and examining the contamination recovered using high magnification. Dangerous residual fibres of asbestos or glass can be recognised visually under magnification.
Organic carcinogens
Some very concerning university research results, reporting the higher incidence of death and serious disease (particularly cancers) in retired firefighters, have already been published by LCN (see issues from June 2018, Jan 2020 and Dec 2023). There is a strong possibility that organic carcinogens released or formed in a strong blaze and then absorbed through the skin or by inhalation could be a contributory factor. This is being addressed by the latest designs of layered fire-wear and by the policy of decontaminating used garments immediately after use. Outer layers are now removed at the scene of the incident wherever possible, and not allowed to come into human contact before decontamination.
There are a great many possible carcinogens in this category. It is possible to try to analyse for each of these. However, a more pragmatic approach is to uprate the power of the decontamination process by the incorporation of a broad
range emulsifier able to cope with all types of oily or fatty organic compounds. Chemicals which are either miscible with or soluble in water are not usually a problem for decontamination by laundering – it is those with an oily or fatty characteristic which might survive the wash.
In order to be certain that the power of the wash process is sufficient to reduce the risk of any organic contaminant surviving the wash, two checks are essential. Firstly, the wash process must be fully validated using garment batches known to be contaminated. This currently forms part of an LTC research program. Secondly, there should be regular simple checks to verify process power using, for example, EMPA test swatches. LTC have already followed the general principles of this approach and refined it for allergen control on food industry workwear, with eminently successful results which are now being widely implemented. Where the precise hazardous contamination is known, it might be necessary to make regular checks on either a garment taken at random or on plain white cotton test swatches, using appropriate analytical methods, able to pinpoint a particular chemical of concern.
Heavy metals
These are loosely defined as metals with high density, high atomic weight or high atomic number. They include cobalt, manganese, chromium, lead and uranium, for example. They are hazardous because they can be absorbed into the human body
quite readily, especially if they are in the form of a soluble salt or combined in a gaseous compound. Lead, for example, affects the brain, heart, lungs, kidneys and bloodstream, and lead poisoning is cumulative.
Tetraethyl lead was added to petrol in the UK in the 1920s to reduce engine pre- ignition or ‘knocking’. From 1970 until the end of the century, it’s estimated that about 140,000 tonnes of lead were released into the atmosphere from tailpipes, in the UK alone. However, since 1999, using lead in fuel has been banned in the UK and most countries worldwide due to evidence that exposure to lead causes developmental problems in children and cardiovascular, kidney, and reproductive problems in adults. National legislators are quite rightly keen to ensure no repetition of this with other potential contaminants. Decontamination of workwear contaminated with any heavy metal usually demands a laundering process with controlled alkalinity and other specific features, to solubilise the target metal or metals. Users can then be expected to request process validation, together with routine assurance checks that the process power continues at the level needed.
Mercury
Mercury vaporises at 356C, so vapour is generated in many fires, including industrial, commercial, educational and residential. Even a broken thermometer or barometer can give rise to concern – the safe exposure limit for mercury can be as low as one part per billion (1 ppb)! The problem is compounded by the fact that mercury has a relatively high vapour pressure throughout the temperature range.
FIERCE BLAZE: Firefighters can be expected to encounter probable carcinogens 18 LCN | October 2024
If there is any chance at all of mercury contamination on a batch of fire-wear for example, an effective laundering process can be designed to deal with this. This is also absolutely essential for operatives manufacturing chlor-chemicals based on electrolysis of brine (which uses a liquid mercury electrode). Protection systems for some outboard motors also rely on a sacrificial mercury anode, to prevent corrosion of aluminium components, for example, so even a boatyard blaze can result in serious garment contamination. Elemental mercury on workwear can be expected to form very tiny droplets, which in a correctly loaded washer extractor might
www.laundryandcleaningnews.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29
