The term ‘protective clothing’ covers a wide range of products, including high visibility garments for workers amongst traffic; flame-proof coveralls for racing drivers; flame and heat resistant turn-out suits for firemen; gas, liquid, and dust proof suits for the chemical industry's workers; chain-mail gloves for butchers; chain-saw stopping trousers for forestry workers; hard hats and hard-toe boots for building workers; welders' UV protective gloves and goggles; hearing protectors, immersion suits, and buoyant garments for workers on water; rescue harnesses and fall arrest systems; bullet proof vests; and a wide range of sports equipment from fencing masks to ice hockey goal keepers' whole body coverage with impact absorbing padding.
Viewed simply, protective clothing is something an individual places between themselves and a hazard in order to stay in the vicinity of the hazard with a reduced risk of injury.
It is better to reduce the hazard than to wear protective clothingThe recognition of the need to use protective clothing is an admission of failure to find another way of carrying out the task that eliminates the hazard or removes the worker or sportsman from the vicinity of the hazard. During the industrial revolution many industries produced uncontrolled hazards such as the dust from cotton spinning and weaving. When the resulting fire risks and illnesses were recognized, regulations and ventilation were introduced to control the dust. Modern protective clothing could allow workers to work in the cotton dust, but the appropriate solution is still to control the dust. Similarly, highly carcinogenic dyestuffs can be handled safely, but it is better to replace them by less dangerous ones.
There remain, however, many situations in which the people cannot be or even do not wish to be separated from the hazard, so apart from using protective clothing increased safety can only be achieved by ending the activity. Cricket would not be the same game if the ball was so soft it could not cause injury. The batsman's pads, gloves, and helmet are the protective-clothing response to the hazard of the high speed hard ball. Health care workers cannot be separated from the infectious patients they treat. They therefore need clothing that is a barrier to bacteria and viruses. Motorcyclists will remain at high risk of severe and fatal injuries from road and vehicle impacts, until they all drive cars. Helmets and leathers are worn to reduce the severity of the injuries in the inevitable accidents that occur.
Is discomfort the penalty of protection?Naturists regard all clothing as an unnecessary impediment to the enjoyment of life and freedom of expression. All clothing has mass and bulk, so it inevitably impedes movements and the free exchange of energy with the environment. In a hot humid climate any clothing is a burden and we would be better off wearing none. However, when the sun shines clothing is a beneficial barrier against radiant heating and ultraviolet burning.
An individual's choice of what regular clothing to wear depends on its availability and cost, changing fashions, cultural conditioning, desire to project a particular image, and perception of comfort. Comfort is a person's subjective evaluation of satisfaction with prevailing conditions, including external physical factors, internal physiological responses, and psychological and emotional state. It is well known that a lot of physical discomfort is acceptable if the right image can be projected. On the other hand, desire for comfort may well have led people to develop clothing that provided a high level of protection long before such a concept was coined. The Inuits' traditional caribou skin garments protect against severe cold, and a cowboy's chaps protect against thorny vegetation.
Protective clothing is primarily developed to prevent a particular hazard causing harm to the person in the clothing. Developers seek materials and construction methods expected to resist the hazard. They consider which parts of the body are most at risk and seek to cover these. If the hazard is a dust or gas they may have to design for total enclosure. Consideration of the wearer's comfort, mobility, dexterity, and level of physiological stress tends to come after the desired protection level has been achieved. Not surprisingly, users complain that this is the wrong way round.
Discomfort is the major unsolved problem with protective clothing. As greater mass and bulk are added to provide specific protection, discomfort escalates. Soldiers may be quite comfortable in a range of conditions wearing under-clothing providing soft skin contact and a battle dress designed to keep them dry, warm, clean, and inconspicuous. However, they soon become very uncomfortable wearing a flak jacket and ballistic helmet as well. Add an NCB coverall (nuclear, chemical, and biological protection) and a respirator, and major physiological strain occurs on exercise. Add climatic conditions such as those in Saudi Arabia and it is obvious that the essential protective clothing is going to become a very big problem to its wearer.
Re-thinking the job may reduce the need for protection and therefore discomfortSometimes a radical re-evaluation of a job results in alternative solutions to the use of protective clothing. Work on the sea bed used to be done by divers in rigid, steel pressure-resisting suits with atmospheric pressure inside. Their capacity for work was very limited. Now divers are compressed in hyperbaric chambers to the pressure at the depth at which they will work, and breathe special helium/oxygen mixtures to prevent subsequent decompression sickness. When at depth they are at the same pressure as the sea water, so they can wear light, non-pressure-resisting suits and do much more work. The disadvantage is that they have to remain compressed for many days and nights, and have to go through a long decompression process before they can safely leave the chambers.
Developing better protection and barrier systems for use in protective clothing may directly and indirectly cause problems. Firemen used to stand back from fires and direct their hoses at the burning buildings. This was not very effective. Modern practice is to get inside the building, and as close to the seat of the fire as possible, and to extinguish it directly. Much higher resistance to flames and to the transmission of heat is therefore needed in the firemen's clothing, and this has progressed from colourful uniforms, through heavy woollen fabrics, to the current multilayer non-flammable thermal barrier systems. The closer the fireman gets to the fire the greater is the need for a thermal barrier, and it is this that causes most problems, because it prevents the fireman's own metabolic heat being lost whether he is near a fire or not. Heat stress is an almost inevitable result. In addition, more mechanical protection is needed close to the fire due to the hazards of collapsing buildings and explosions; this adds to the weight, bulk, and stiffness of the clothing and hence to harder work with a higher heat output by the fireman.
Standards for the performance of protective clothingProtective clothing can be regarded as an aspect of occupational health. It is worn to prevent injury or ill health due to contact with a hazard. The performance of the clothing when it is needed may be critical, but its ability to deliver the performance may not be obvious to potential users. Therefore there has been extensive activity to produce standards for protective clothing so that purchasers can be told what the clothing should do. This work received great impetus with the publication of Council Directive 89/686 of 21 December 1989, by the European Union Commission. The Directive covers all personal protective equipment (PPE), including clothing, and it lists certain basic health and safety requirements that protective clothing must meet. The response of industry, Standards authorities, Test Houses, and users' organizations has been to work on harmonizing the protective clothing standards existing in European countries, and to develop new standards. The work is now usually being done with ISO (the International Organisation for Standardisation) resulting in worldwide participation and application. By 2001 over 250 PPE standards had been published and 100 were under development. It is only through the application of standards and the mandatory provision of understandable information to users that people will be able to make rational decisions about the protective clothing they need, and to identify it.
Standards for the ergonomics of protective clothingAs with the development of protective clothing itself, early standards concentrated on test methods and specifications for the protection offered. The physiological needs of the users were largely ignored. The ergonomics of the PPE were not taken seriously. Partly this was because it is much more difficult to specify and measure the lack of hindrance to movement, or to define methods for measuring discomfort, than it is to measure, say, the rate at which toxic chemical penetrates the coating on the fabric. Partly it is also because traditionally only the protection was specified.
The main ergonomic problems identified so far are that protective clothing is too heavy, too bulky, too hot, too ill-fitting, too tiring to wear, and too ugly. The subjectivity of these characteristics makes standards hard to define. What is too heavy? For whom is it too heavy, and when? Furthermore, the results of the use of test panels of subjects to evaluate comfort are generally too imprecise and unrepeatable for certification to standards.
Though most people can recognize symptoms of discomfort and over heating, they will not realize their own deterioration in mental performance, so in relatively familiar surroundings heat strain can develop with fatal consequences. It is said that up to one in a hundred workers in some industries suffer heat strain each year. Certainly some sportsmen and soldiers are known to die of heat strain. It is obvious that their protective clothing could be a contributory factor and that they need better information about the hazard of over heating.
Thermal effects of clothing on users are related to the weight, the bulk, the sweat impermeability, and the basic thermal properties of the fabrics. Both thermal effects on users and the thermal properties of clothing can be measured, so standards are being developed in this important area.
Ventilated, refrigerated, or liquid-cooled suits are means by which extreme environments can be survived, but they are hugely expensive and often impractical. In reality options are limited in many sports and in industry. Therefore heat stress will occur. The main contributory factors are high air temperatures, high radiant heat absorption by the clothing, high humidity, low air velocity, high clothing insulation and coverage, high metabolic heat production, and long duration of exposure. The last three are the most significant. Obviously the accumulation of heat can be reduced by wearing less protective clothing, working less vigorously, and working for a shorter time. Thus those managing a work-force or a sporting event have a significant responsibility for the well-being of individuals who may be unaware of impending hyperthermia.
What should be done in extreme circumstances?Some past human activities have left materials and situations now recognized as extremely hazardous and in which remedial workers would have to wear sophisticated protective clothing to obtain even partial protection. Stripping asbestos insulation off boilers and from fire barriers, decommissioning chemicals and munitions factories, making damaged nuclear reactors safe, and clearing landmines are examples. If protective clothing is only partially effective and itself causes heat stress, perhaps it is the wrong solution. The job should be done another way, or perhaps it should not be done at all. If for imperative reasons of public safety the job apparently has to be done, and has to be done by workers in close contact with the hazard, there will be injuries and possible deaths. Who should take the decisions balancing the level of the hazard, the risk of injury, the practicality of providing protective clothing, the cost of remote operation versus the cost of sending in people, and the benefit to society of the job being done compared with it being left undone?
See also cold exposure; diving; ergonomics; heat exposure; work and the body.
"protective clothing." The Oxford Companion to the Body. . Encyclopedia.com. (November 22, 2017). http://www.encyclopedia.com/medicine/encyclopedias-almanacs-transcripts-and-maps/protective-clothing
"protective clothing." The Oxford Companion to the Body. . Retrieved November 22, 2017 from Encyclopedia.com: http://www.encyclopedia.com/medicine/encyclopedias-almanacs-transcripts-and-maps/protective-clothing