Technology

Low back pain and other injuries occurring to the workers during the manual lifting tasks in the work place are one of the most significant issues concerning the health and safety of the workers. The organizations have initiated several new programs and activities for the betterment of workers health issues in the past, still the injuries of workers in this field bear a large percentage of affliction and economic costs affecting organizational performance as well.

Since the last two decades, the National Institute for Occupational Safety and Health (NIOSH) has played a key role in the identification of significant issues concerned with the injuries of workers in the work place. The institute has published a report, namely Work Practices Guide for Manual Lifting in 1981. The report proposed an analytical study for the manual lifting tasks by suggesting different approaches for domineering potential hazards during the lifting tasks and using the mathematical approach via equations weight calculations.

Job Description
While working in a textile factory, the worker during his shift has to feed a reel of threads to the machines. This task requires worker to actually do it mechanically by lifting the reel from the stock and then feeding it to the machine, which is usually situated at some height. The shape of reel is such that worker cannot lift it from the bottom. The diameter is 24 inches and the length between workers hands is approximately 12 inches. The total weight of reel is 45 lbs normally.

Analysis
The activity is assumed to occur once per shift so we can calculate F  0.2. We will also assume its duration to be 15 minutes.

Result and analysis
The weight which is to be lifted is 45 lbs, which is significantly larger than RWL at origin and destination which are found out to be 23.7 lbs and 22.37 lbs respectively. Also the LI is found out to be 1.8987 and 2.01. These values indicate that lifting this weight and outing it at destination is hazardous for most of the workers.

An example described here demonstrates the fact how the altered practice of the same work can be important for reduction of the amount of physical stress that is related to this kind of manual lifting job. This type of work is also dependent upon the conformity of the worker doing that job, as well as adaption and amendments needed for that specific physical job.

Proposed Modifications
The proposed modifications by funding out the above results will be
HM value is larger at the origin, so if the object is brought closer to the destination and then mechanical force is used in the form of worker, then hazard will be reduced.

Either the point where thread reel is placed in the machine should be lowered or the worker should lift up before he lifts the object. This will increase VM value and as well as DM value if both of these strategies are applied.

Loading reels from a certain angle of 90 degrees will help reduce the hazards as location of hands at origin is now changed.

After applying these modifications, if LI is still found out to be greater than 1, then vertical height of destination should be lowered. This will reduce VM and DM. Further weight and size of the object should be reduced to minimal levels. This can be done by using smaller reels and repetitive processing.

Summary
The manual lifting is a task that cannot be eliminated practically from the wok field. It indicates the fact that ergonomic study and design are more resourceful to use it as a controlling approach from the hazardous consequences. This strategy is aimed to reduce the dangers of loading conditions in the work field and also teach the best ways to avoid traumatic movements of body. So, the equations and methods provided in this document for the manual lifting tasks were basically designed to resolve ergonomic problems and also examine different solutions for ergonomic designs. Evaluation of the task presented here indicates that dangerous consequences related to this job can be examined, and in turn, be resolved by considering importance of the alternative designs to pursue in this kind of manual work.