Apparel manufacturing is a labor-intensive assembly line process requiring significant amounts of repetitive and skilled manipulations. Therefore, like any other manufacturing industry, it has its own share of ergonomic problems where poorly designed and unorganized workstations contribute to musculoskeletal discomfort among the sewing operators. Research has found that ergonomic interventions including redesign and proper adjustment of workstations, use of ergonomically-designed seating, and training in low-risk methods and posture substantially improve workers’ efficiency.
- 1 What is ergonomics?
- 2 Improved ways for doing certain tasks related to the apparel industry
What is ergonomics?
Ergonomics is a science that focuses on designing a job for the worker. An ergonomically-designed job would ensure that a taller worker had enough space to safely perform his or her job, and also that a shorter worker could reach all of his or her tools and products without reaching beyond a comfortable and safe range. The opposite to this, and what typically happens in the workplace, is that a worker is forced to work within the confines of the job or workstation that is already in place. This may require employees to work in awkward postures, perform the same motion over and over again or lift heavy loads – all of which could cause work-related musculoskeletal
These injuries often start as minor aches and pains but can develop into disabling injuries that affect our activities of daily living such as laundry, hobbies (knitting, golf, etc.), and even the ability to pick up our children. Ergonomics aims at preventing injuries by controlling the risk factors such as force, repetition, posture, and vibration that can cause injuries to develop.
Some fundamental ergonomic principles that should be followed in our workplaces are…
Use proper tools
Tools should be appropriate for the specific tasks being performed. Tools should allow you to keep your hands and wrists straight – the position they would be in if they were hanging relaxed at your side. Bend the tool – not the wrist! The tool should fit comfortably into your hand. If the grip size is too large or too small it will be uncomfortable and will increase the risk of injury. Tools should not have sharp edges, create contact stresses in your hand, or vibrate.
Keep repetitive motions to a minimum
Our workstations or tasks can often be redesigned to reduce the number of repetitive motions that must be performed. Using a power-driven screwdriver or tools with a ratchet device can reduce the number of twisting motions with the arm. Some tasks can be automated or redesigned to eliminate repetitive movements and musculoskeletal injuries.
Avoid awkward postures
Your job should not require you to work with your hands above shoulder height on a regular basis. Arms should be kept low and close to your body. Bending and twisting of your wrists, back, and neck should also be avoided.
Use safe lifting procedures
Avoid lifting objects that are too heavy. Use more than one person or a mechanical device to reduce the load. Your workstation should not require you to lift objects above your head or twist your back while lifting. Keep the load close to your body and ensure that you have a good grip. Heavy and frequently lifted objects should be stored between knee and shoulder height – not on the ground or above your head.
Get proper rest
You need to rest your body and mind in order to prevent injuries. Give your muscles rest during your coffee breaks, lunches and weekends by doing something different from what you do in your job. For example, if you stand all day while performing your job you should sit down to rest your legs and feet during your breaks. If you sit down when working you should stand up and walk around during your breaks to give your back a rest and to increase circulation in your legs.
- The analysis of a workplace is crucial to establishing a safe and effective system for an operator to work in. ‘Ergonomics’ in a workplace is usually controlled by two broad factors: Human factor or ‘cognitive’ ergonomics influenced by decision-making process, organization design, human perception relative to design; and ‘industrial’ or ‘physical’ ergonomics which involves physical aspects of the workplace and human abilities such as force required to lift, vibrations and
- To find a solution, first, the problem has to be Some of the common problems faced by a worker include:
This can make tasks more physically demanding by increasing the exertion required from smaller muscle groups and preventing the stronger, larger muscle groups from working at maximum efficiencies. Handling or assembling very small parts and materials or performing extremely precise tasks may contribute to eye strain and awkward postures.
Force is the amount of muscular effort expended to perform work. Exerting large amounts of force can result in fatigue and physical damage to the body. Pressure points result from the body pressing against hard or sharp surfaces.
Tools that are not properly maintained or are inappropriate for the task may increase the amount of hand-arm vibration and result in fatigue, pain, numbness, and tingling increased sensitivity to cold, and decreased sensitivity to touch in the fingers, hands, and arms.
Repetitive work involves duplication of certain motions over and over again resulting in awkward postures and forceful exertions of the same muscles, tendons, or joints. This subsequently increases the risk of injury and results in wastage of time leading to delays in production.
Therefore, one must analyze the work environment thoroughly and understand each worker’s need to apply ergonomic solutions making the work atmosphere congenial.
The requirements for a sewing table to be considered are height, size, shape, tilt, and legroom. Lack of task lighting (local lighting) is often an important deficiency noticed in the sewing machine. The workers complain of headaches and occasional accidents like needle-piercing because of the visual strain caused by insufficient light at the point of operation. The hazard identification and risk analysis indicated insufficient illumination as a risk for the sewing machine operators.
A good height for sewing tables is at or slightly above the elbow height. The height should be easily adjustable with the press of a button. Sewing tables can also be modified to meet the requirements of specific garments, machines, or operators by making the table smaller to allow carts to get closer to the sewing machine. Putting an extension on the table to increase its size can help to support the weight of larger garments or even act as an input location for the sewing table. Raising the edges of the table prevents the material or components from falling down. A sewing table tilted at 10° to 25° towards the operator, improves the visibility of the task and helps to keep the neck in a more upright position. The appropriate height of the table also gives the operator sufficient legroom.
The chair is a critical piece of equipment for sewing machine operators who work in a seated position. It can have a very large impact on the comfort of the worker and can affect the risk of muscle pain and injury.
Adjustable chairs reduce the shoulder and neck pain of the operators. A custom-designed chair is adjustable in height, has no wheels to ensure that the operator stays firmly seated in place, has no arm support to interfere with the movements, and has a seat pan that slants slightly downward to support forward-leaning postures. The chair is also upholstered with a breathable cloth and foam appropriate for the high-temperature environment of the garment shopfloor.
For seating and standing work, the workstation height should be such that it allows workers to function with elbows placed at 90 degrees. This will reduce stress on the body. If the workstation is too low, the worker is forced to bend at the waist to reach the work being done. This puts stress on the lower back. If the station is too high, the worker is forced to lift his shoulders or move elbows away from the body to reach the work. This puts increased stress on the shoulders which may lead to injury. During seated work, if good back support is not present or used, the body is subjected to static postures, which results in constant use of the back muscles. Therefore, it is important to adjust the workstation in order to allow the worker to use the backrest. It is also important to adjust the worker’s chair for him to work in a comfortable body position.
Most sewing machine operators use one treadle, which controls the direction and speed of the sewing machine. Some operators use additional smaller pedals that lift the presser foot or cut the thread.
One can increase the size of the treadles by placing a thin wooden board over the surface of the pedal, thus positioning it at the most comfortable position and angle for the operator. This way, if there is a requirement of a pedal, it will be at the same angle and position as the treadle, thus making it easily accessible by one of the feet. If only one foot is being used, a footrest should be located at the same height and angle as the treadle. Pedals for standing operators have to be close to the floor in order to support his body weight over both feet. The pedal could also be moved so that the operator is able to rotate between activating the pedal with his right or left foot.
Knee switches and hand controls
The knee switches are often not conveniently located for the operator.
Place the knee switch at a convenient position for the operator so that it rests very close to the leg, just above the knee, and ensure that it is also well-padded. Make sure that the controls are located at a place that does not have any obstruction. In addition, controls should activate with a light feather touch even from different angles.
Without proper lighting, an operator may be encouraged to adopt poor postures in order to see his work better and may subsequently strain his eyes or be less productive. Lighting requirements may vary depending on the task, fabric, and individual preferences.
Ensure that there is good general lighting and task lights are provided to the operators who desire them or have visually demanding tasks. The task lights should have a “goose-neck” so that the lights can be directed to the work area. Lampshades should have ventilation holes, but wherever necessary, these could be covered so that the light is not directed through these holes towards the operator disturbing his concentration.