Ergonomic hazard

Ergonomic hazards are physical conditions that may pose a risk of injury to the musculoskeletal system due to poor ergonomics. These hazards include awkward or static postures, high forces, repetitive motion, or insufficient rest breaks activities. The risk of injury is often magnified when multiple factors are present.
Environmental, operational, or design factors can all negatively impact a worker or user; examples include whole-body or hand/arm vibration, poor lighting, or poorly designed tools, equipment, or workstations. Some of the common body regions where injuries may occur include:

Muscles or ligaments of the lower back
Muscles or ligaments of the neck
Muscles, tendons, or nerves of the hands/wrists
Bones and muscles surrounding the knees and legs

Injuries in these and other parts of the body could result in musculoskeletal disorders, which may be called cumulative trauma disorders or repetitive strain injuries, and are estimated to account for about a third of all non-fatal injuries and illnesses and their associated costs. Ergonomic hazards occur in both occupational and non-occupational settings such as workshops, building sites, offices, homes, schools, or public spaces and facilities. Finding ways to eliminate or reduce ergonomic hazards in any setting will ultimately reduce the risk of injury.

Causes

Awkward posture

Awkward posture is when the body deviates significantly from a natural position during work-related activities. Awkward posture reduces work efficiency due to unnecessary overexertion. When awkward posture is sustained for a long period of time, muscles and nerves may become pinched. Examples include twisting, reaching, pulling, lifting, bending, or any other posture that can cause pain when sustained for a prolonged period.

Static posture

Static posture, or static loading, is when a person holds a consistent posture during the entirety of the time it takes to perform a task, which does not allow the body to relax. It is a problem because it can lead to muscle pain, fatigue, and joint issues, and increases the risk for musculoskeletal injuries. The degree of damage depends on the type and duration of posture, as well as the type of activity. Issues related to static posture among workers can be prevented by taking frequent breaks and stretching often.

Contact stress

Contact stress occurs when some part of a worker's body—such as the knees, elbows, wrists, or fingers—touches or rubs up against a sharp, inflexible, or immobile surface repetitively or for a long period of time. The surface could be a workstation, ladder, floor, or handle of a bucket or tool. Contact stress can also be created through pushing, gripping, pinching, pulling, and lifting objects that can place additional force on the body's joints. Increasing these forces requires additional muscle exertion, and places greater loads on joints and connective tissues which can cause fatigue and may contribute to musculoskeletal disorders when there is inadequate time for rest and recovery.

Repetitive motion

Repetitive motion is prolonged, repeated movement which causes muscle fatigue and eventually results in nerve damage. This motion can injure soft tissues, such as nerves, muscles, and tendons; examples of injury include tennis elbow, carpal tunnel syndrome, tendonitis, and bursitis. These motions require breaks during activity to help the nerve or muscles rest and recover.

High forces

High forces involved in some physical labors can injure muscles and joints. Overexertion can occur when an external or muscular force exceeds the force the body can safely endure. The force might come in the form of gripping, pinching, pushing, pulling, and lifting objects.

Prevention

Prevention of ergonomic hazards and musculoskeletal disorders is multifaceted and can be complex. Importantly, ergonomics tries to fit the job to the worker, not the worker to the job. One way to approach ergonomic hazards is to use the Hierarchy of Controls—a system published by the National Institute for Occupational Safety and Health that describes how to manage hazards by elimination, substitution, engineering controls, administrative controls, and personal protective equipment.

Elimination is the practice of removing a hazard from the work operation so there is no longer risk of harm. This is the most effective solution. For ergonomic hazards, this could involve:
# Redesigning the work area to remove the need for prolonged reaching, bending, or maintaining awkward postures.
# Providing carts, dollies, or jacks to move heavy items so they do not have to be lifted.
Substitution is the practice of replacing the current hazard with one that is not as harmful. For ergonomic hazards, this could involve:
# Replacing heavy materials with lighter alternatives.
# Replacing a low-quality chair or equipment with higher-quality, softer, or padded materials.
Engineering control is the practice of physically separating a hazard from the worker. For ergonomic hazards, this could involve:
# Designing frequently lifted items to have easily gripped handles.
# Providing adjustable chairs, tables, stools, or workstations that can be fitted to a specific worker's height.
Administrative controls are policies and regulations in the workplace that help prevent a hazard. For ergonomic hazards, this could involve:
# Rotating workers between tasks so people are not using the same muscle groups for an extended period of time.
# Providing sufficient breaks for workers to rest.
# Storing heavy materials at waist level.
# Providing employee training for safe lifting.
Personal Protective Equipment controls are typically items a worker wears to protest them from a hazard. For ergonomic hazards, this could include:
# Back braces
# Lifting belts
# Lifting straps
Office ergonomics

Ergonomics tries to fit the job to the worker, not the worker to the job. Whenever there is a worker and a job, there will be ergonomic considerations. Commonly, ergonomic issues can arise in an office setting. Many people who work in an office often spend hours sitting and working in the same position. Enough breaks should be planned to give strained muscles the opportunity to recreate from the static posture. Ergonomic considerations include chair and computer monitor height adjustment, lighting position, break frequency, and chair design. The efforts taken should be proportional to the amount of time spent sitting.

	Measures
①	Top of screen equals eye-line with a distance of at least 50 cm
②	Screen is placed perpendicular to windows and no light source is pointing at the screen
③	Lumbar support for the back
④	Adjustable arm rests allowing the elbow being oriented close to 90°
⑤	Hands rest on the desk with the same level as keyboard and mouse
⑥	Rocking mechanism promoting active sitting
⑦	Extendable seating surface
⑧	Height adjustable chair allowing the kees being oriented close to 90°
⑨	Feets are evenly on the ground or supported by an angled rest
⑩	Head support
⑪	Surface specific rollers for carpet or concrete

Depending on user preferences an ergonomic keyboard and ergonomic mouse can be helpful.
Sedentary lifestyle leads to an unhealthy amount of inactivity, loss of strength and obesity. Even with an ergonomic environment such person cannot maintain an ergonomic posture. Supplemental physical activity, fitness training and sports is required to sustain a healthy life on long-term.

Manufacturing ergonomics

Those working in manufacturing settings are prone to repetitive actions, awkward postures, high forces, and prolonged exposure to vibrations from equipment and tools. These exposures can result in increased rates of musculoskeletal disorders and cumulative trauma disorders. Specific risk factors include physical activities, bending and reaching for loads, twisting the body, and other high-intensity and energy-exerting tasks.
It is important to manage ergonomic risk factors and reduce employee exposure to those risk factors. Effective ergonomics practices can improve employee health, increase productivity, increase manufacturing quality, decrease cost, improve profitability, and create and grow a better, healthier team of employees.
The following tips and practices can be implemented by employees and company management alike to help improve ergonomics in the manufacturing setting.
Awkward posture
Workstations should be kept at an appropriate height for the employee, based on their needs and the task being performed. The work surface should be at an appropriate height, with commonly used items within easy reach to prevent the need for reaching and awkward stretching. Stools or chairs should be provided when appropriate for tasks to reduce the time employees need to stand. Knee pads should be provided to prevent the need to squat if work needs to be done on the ground.
Static posture
Assembly line workers who stand for the duration of a shift may experience negative effects over time. Switching tasks, taking breaks, or providing the option to sit can help reduce static postures.
Contact stress
Using lifting aids can reduce or eliminate the force placed on the employee's body during lifting tasks. Using carts, conveyors, or automated guided vehicles can help employees manage and carry heavy loads better, or even automate the lifting and carrying process.
When transporting heavy loads, try to push the load rather than pull. Pushing uses the body's stronger back and leg muscles. Ensure that the wheels on a cart or transporting device are appropriate for the surface on which it will be moved, as well as the materials it will be moving. Make sure preventative maintenance is performed on carts and moving equipment so they can continue to be used properly.
Repetitive motion
Using, and training employees on how to use, proper lifting techniques can ease the burden of awkward lifting postures. Lifting by bending at the hips and knees, and lifting within the "lifting safety zone", can reduce forces on parts of the body while lifting.
High force
High forces in the manufacturing industry can come from the lifting of products from one point to the other. Prolonged exposure can be problematic, as it increases stress and fatigue on the muscles and joints, which over time causes pain and discomfort.