Every so often, I have a load of "dry-clean only" garments and I am reminded of the dry cleaning process and its inherent hazards. Cruising the Internet, I found a very informative article on
http://www.science.com/. Below is a description of a standard operating procedure (SOP).
Tagging and inspection - Some method, whether it is small paper tags or little labels written on a shirt collar, is used to identify your clothes so they don't get mixed up with everyone else's. Clothes are also examined for missing buttons, tears, etc. that the dry cleaner might get blamed for otherwise.
Pre-treatment - The cleaner looks for stains on your clothes and treats them to
make removal easier and more complete.
Dry cleaning - The clothes are put in a machine and cleaned with a solvent.
Post-spotting - Any lingering stains are removed.
Finishing - This includes pressing, folding, packaging and other finishing touches. [1]
Doing my own laundry, I like to compare my procedure to that of the professionals. With regard to pre-treating stains, I must admit that I don't do that very often. That also is a reflection of the fact that I try to be very careful. When working with solvents or chemicals, I rarely wear clothing that I care enough about getting stains. For example, when painting or changing the oil in my car, it is common sense to wear items of clothing you don't care about, like an old, long-sleeve shirt and pair of jeans. I have a specific set of clothes I use only for working on my car, keeping them in the garage. However, by keeping them in the garage to isolate them from my other clothes, I forget to wash them on a regular basis. Although it does seem wasteful, I will most likely end up throwing away those clothes after a while instead of washing them. There is no shortage of old casual clothing that I no longer wear that can then be used for yardwork or working on the car. The old business clothing is more likely to be donated to the Goodwill or Salvation Army.
Nevertheless, some stains seem to be unavoidable at some point in everyone's lives. That, of course, would be food stains. Whether eating fast-food garbage or an over-priced restaurant meal, getting some on one's clothes happens to adults and children alike, albeit with varying frequencies. I learned something useful about pre-treating, perhaps common knowledge to some:
Simply apply water for wet stains (a stain that had water in it) and solvent for
dry stains (a stain that has grease or oil in it). Then, gently tap and blot
both sides of the fabric with a soft cloth so the stain "bleeds off" onto the
cloth. Then, rinse the fabric, let it dry and your cleaner will do the rest. [2]
How to treat wet stains is common sense but I didn't even know what a "dry stain" was, much less how to treat it. The greatest challenge, to me at least, was to treat the "ring-around-the-collar" on my business/dress shirts. I would place that in the "dry stain" category due to the oils contained on human skin that can't help but rub off on collars throughout the work day, even worse when giving presentations, going on interviews, etc. White dress shirts are the most noticeable victim of this affliction. I learned long ago to start wearing off-white or blue dress shirts. White seems to be the best backdrop to notice all the little stains one might come across and appears to be very obvious when its brightness starts to fade. After an exhaustive online search, there appeared to be a myriad of methods to treat the stain.
Common among the suggestions was to treat the stain immediately, washing the garment soon after its wear. However, this is contradictory to water-conserving practices. The suggested solvent varied from solvents specifically marketed to remove sweat/perspiration stains to pre-soaking in white vinegar or ammonia. In the dry cleaning industry, the solvent of choice is perchloroethylene or PERC.
Perchloroethylene (PERC) is the most commonly used drycleaning solvent. PERC can enter the body through respiratory and dermal exposure. Symptoms associated with exposure include: depression of the central nervous system; damage to the liver and kidneys; impaired memory; confusion; dizziness; headache; drowsiness; and eye, nose, and throat irritation. Repeated dermal exposure may result in dermatitis. [The National Institute of Occupational Safety and Health,] NIOSH considers PERC a potential human carcinogen. [3]
Due to the adverse health effects of PERC use, alternatives have been sought. Among the alternatives and their respective advatages/disadvantages are described below.
Modern wet cleaning is a new method to clean by water immersion garments normally cleaned in solvent.
Advantages of Wetcleaning
Fewer health and safety hazards
Soil contamination and large emissions of air pollutants eliminated
More pleasant smell than solvent
Some soils are more easily removed (i.e. sugars, salts, drinks, body fluids, starch, and milk)
Comparable cost to cleaning with PERC
Burden of strict health, safety, and environmental regulations reduced
Disadvantages of Wetcleaning
Not currently a complete replacement for cleaning with PERC
Potential for fabric deterioration, structural surface changes, felting, loss of luster and shape, dye transfer or color change
Wools, silks, and rayons are more subject to fiber shrinkage or bleeding of dyes
Greases, oils, waxes, and resins are more difficult to remove
Large quantities of contaminated wastewater
Labor-intensive, requires highly skilled workers
Presents additional ergonomic risks to workers because it is more labor intensive [4]
Petroleum-based drycleaning has been used in garment cleaning for many years.
Advantages of Petroleum-Based Drycleaning
Generally considered less toxic than PERC based upon exposure limits. Toxicological properties not as well documented as PERC.
Because the vapor pressures are lower than PERC, exposures due to inhalation are generally lower
Established cleaning solvent that is effective at cleaning all types of garments
Generally less expensive than PERC
Disadvantages of Petroleum-Based Drycleaning
Presents fire hazards; PERC does not. Fire codes may limit where some shops using these solvents may be located.
Better living condition for bacteria growth. Bacteria cause the garments to retain unpleasant odors.
Lower vapor pressures result in a longer drying process than ERC.
Less effective at removing oil and grease stains than PERC
Higher insurance premiums than with PERC [5]
Liquid carbon dioxide is a recently developed technology that is not yet on the market.
Advantages of Liquid CO2
Environmental concerns such as soil contamination, air pollution, etc. eliminated.
Shorter expected cycle time than with conventional drycleaning, reduced garment pressing time.
Potentially more effective in cleaning suede, leather, and fur than with conventional dry cleaning.
Relatively high PEL of 5,000 ppm
Disadvantages of Liquid CO2
Potential safety hazards--high pressure system, asphyxiation
Questions regarding garment redeposition of stains that have been removed
Possible problems removing protein stains such as grass, lipstick, or chocolate
Possibly more expensive than PERC machines
Very new technology for garment cleaning applications that has not stood the test of time[6]
Sufficed to say, I have very little in common with current and future dry-cleaning practices with specific regard to the choice of solvents. However, perhaps the greatest commonality between individual and commercial clothes washing occurs during the finishing or pressing phase. Having done quite a bit of ironing in my time, I have noticed several occupational hazards common to both the professional and average consumer, for example, standing for long periods of time, the potential of burning oneself, and the stress of repeated movements. Such stress of repetitive movements in detail below:
Musculoskeletal disorders are caused by repetitive motions, awkward postures,
excessive reaching, and precision gripping. In the drycleaning industry,
ergonomic risks occur during garment transfer, pressing, and bagging. These
activities, combined with a high work rate and frequency, may cause physical
discomfort and musculoskeletal problems for workers. Disorders can include
damage to tendons, muscles, nerves, and ligaments of the hand, wrist, arm,
shoulder, neck, and back. [7]
I have gone on my own ironing binges, ironing some 25 dress shirts at a single sitting, and I have experienced the physical stress of repetitive motions and long periods of standing. In particular, I have found that the longer the time spent on ironing, the greater the possibility of burning oneself. This has happened on numerous occassions. Fatigue, coupled with a narrow ironing board on a plush carpet, has led to many burns. This has led me to seek more professional irons and acessories. I have long hated the average consumer iron with its metal sole plate, heavy iron with water reservior, and cord that inevitably wind around and gets caught on something. Cord minders and ways to counterbalance its weight have been developed (Figure 1).
Also, there are steam-only irons where the sole plate is not heated and the only potential for burning is getting scalded from a blast of steam. This, I would imagine, virtually eliminates the frequency of burns.
Lastly, the weight of an iron is decreased when using a gravity feed iron, where the water reservoir is separate from the iron (Figure 2). This decreases fatigue when ironing for long periods of time.
Figure 2. Gravity feed iron.
[1] Marks, Nate and Debra Luhring, "How Dry Cleaning Works,"
http://science.howstuffworks.com/dry-cleaning2.htm[2] Ibid.
[3] National Institute of Occupational Safety and Health, "Control of Exposure to Perchloroethylene in CommercialDrycleaning (Substitution),"
http://www.cdc.gov/niosh/hc17.html[4] Ibid.
[5] Ibid.
[6] Ibid.
[7] National Institute of Occupational Safety and Health, "Control of Ergonomic Hazards in Commercial Drycleaning,"
http://www.cdc.gov/niosh/hc22.html
