Fundamental of Occupational Hazards Health Effects

0905(2)601

Occupational hazards
In
the cotton textile industry

Name: Mohamed Salem Mahmoud Salem

Code No: 0905 – 2 -004

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 Occupational hazards in the cotton textile industry

Introduction

The textile industry consists of a number of units engaged in spinning, weaving,

dyeing, printing, finishing and a number of other processes that are required to
convert fiber into a finished fabric or garment.

In this article, we will look at occupational risks related to Cotton Yarn

Manufacturing

Cotton Yarn Manufacturing (Cotton Yarn Spinning)

Cotton spinning process consists of many stages as shown below, the stages differ
depending on the type of the cotton yarn you are producing whether it is a carded
cotton yarn or combed cotton one.

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Major processes

1- Opening, blending, mixing and cleaning.

Opening and cleaning is the first operation which takes place in the spinning
mill. The department where cleaning and opening is called Blow Room, it is
called this way because the cotton is transported from one machine to another
by blowing it through the ducts. Blow room is combination of machines varying
significantly unlike other processes in spinning.
The main objective of the blow room is to open, mix, clean and even feeding to
the next process, which is carding.

An Example of Blow Room Sequence

(1) The automatic bale opener (2) A condenser drum (3) beater/grid-bar-airflow
system (4) multi-stack continuous blender (5) multi-beater cleaner for intensive
opening and cleaning (6) a final deducting step.

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2- Carding
It is a mechanical process that disentangles, cleans and intermixes fibers to
produce continuous web or sliver suitable for subsequent processes.

3- Combing.

Combing is the process of preparing carded sliver for spinning. Combing

separates out short fibers by means of a rotating ring or rectilinear row of steel
pins.

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4- Drawing
Drawing is one of the simplest processes here; a number of slivers from the
carding are stretched to make one sliver. This process is purely done to
improve the evenness of the end product. A thin spot in one sliver when mixed
with 5 to 7 and sometime more sliver becomes insignificant. The Drawing
stages might be one or two.

5- Simplex /Roving

This is an intermediate stage before the final yarn is made in the next stage.
The problem with the sliver is that it is too thick to put directly into spinning. To
make yarn it needs to be stretched gradually the simple/roving is just an
intermediate drawing stage, here the sliver is get stretched and slightly twisted
to keep the strand intact while transporting to next stage.

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6- Spinning

The rovings are taken to the ring frame, which stretches the roving to the
required thickness and imparts twists to give strength to the yarn.

Stretching is performed by increasing the speed of the roller pairs gradually so

the back roller pair runs slower than the middle pair and the middle pair runs
slower than the front creating a stretch in the fiber strand (stretching is
performed same way in drawing and simplex too).

7- Winding
In this stage the spinning bobbins is being
converted to a packages for better transportation
and longer yarn in the package. Also this stage can
work as a quality control on the yarn where all thin
areas and thick areas can be eliminated for better
more even yarns

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 Subjective Hazards
And
Control measures

A- Physical Hazards
1- Noise

 RISKs

- Occupational hearing impairment.

- Communication interference and safety.

- Effects on job performance.

- Annoyance.

 SOURCEC

- High spindle speeds reached on new machines (ring spindles up to 20000 rpm,
rotor speed up to 11000 rpm).

- Ducts and pipes

Vibrating duct is the common cause of noise. The source of noise is the fan

- Machine behavior

Any machine while in running is prone to develop the noise and textile
machines have no exception for the same. When we talk about the noise with
respect to machine it is the vibration generated due to two or more solid
surface interface. The vibrating members alternately push and pull against air
creating noise, off course there are many reasons for generation of noise and
can be summarized as follow:-

1) Machine footing and its foundation.

2) Type of mechanism adopted while designing the machine (no. of mechanical

components presented and linkage mechanism)

3) Working speed of machine.

4) Maintenance of machine.

5) Design of other machine parts like blowers, ducts and pipes etc.

6) Material handling system.

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 Control measures
* Engineering control;-

1) Proper maintenance.

It is recommended that a good preventive maintenance practice

should be adopted to reduce the noise level and also follow
scheduled check list for lubrication to reduce the wear and tear of
parts and maintain the same.

It is observed that malfunctioning or improperly maintained parts

produce more noise that well maintained one like,

 Loosely held bearings and belts.

 Torn belts
 Worn gears
 Imbalanced rotating masses
 Missing guards or shields
 Improperly adjusted cams and linkages

2) Room treatments:

One of the basic principles of noise control is to reduce the reflecting

sound, for that use of absorbent materials in between the
departments, modify the plant construction according to the acoustic
principle and engineering approach

3) Relocation of equipment:

Noise level drops off when the distance from the noise source is
increase.

 Noisy equipment should be as far as possible from employees.

 Do not put noisy parts at corner to avoid noise reflection

4) Simple machine treatments:

Many simple modifications in the machine show significant reduction

in the noise level.

 Reduce the dropping height of parts from bins and storage tanks
 Enclose the bin and boxes with rubber base material to absorb
the noise
 Keep optimum pressure when working with pneumatics and
hydraulics.

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 5) Proper operating speed:

As we know any increase in speed will prone to develop more noise so

run the machines with manufacturer recommendation.

6) Using proper machine speed

*Administrative controls;-

- Design and planning:

First step in effective noise control is design and purchase in noise

control in mind.

Take noise control in account when designing new facilities renovating

existing buildings.

Isolate noisy operations in designing rooms where fewer employees will

be impacted.

Use qualified engineers and architectures to design the work place and it
becomes easier to control techniques before machine installation and
other aspects. Before buying anything ask to the manufacture about the
noise and other technical parameters related to noise generation.
- Operating procedures and equipment replacement technique.

- Replacement of old equipment with quieter new models.

- Adherence to equipment maintenance programs.

- reduce noise doses by limiting exposure time.

- PPE.

- Pre- employment and periodic medical examination.

- Record Keeping.

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 2- Heat stress

 RISKs

- Systemic Disorders.

- Heat syncope.

- Heat oedema.

- Heat cramps.

- Heat exhaustion.

- Heat stroke.

- Skin Disorders

 SOURCEC

- Spinning sometimes requires high temperatures and artificial

humidification of the air.

 Control measures
* Engineering control;-

- Opening windows in hot work areas.

- Using fans, or Using other methods of creating airflow such as exhaust

ventilation or air blowers. Use air conditioning to cool the entire workplace
if possible.

- Use spot cooling for hot areas and work sites.

- Use local exhaust to remove heat from hot work processes.

- Insulate hot equipment and surfaces to contain radiant heat.

- Ensure that maintenance program quickly and effectively fixes problems

that create hot conditions—such as steam leaks.

- Cover or contain heat sources—such as steaming tanks, vats and drains.

- Fans can increase the air flow and reduce humidity. Improving the air
flow increases the cooling effect of sweating. However, if the air
temperature is at or above body temperature, fans will simply expose the
body to more hot air. This increases the heat load and the risk of heat
stress disorders.

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*Administrative controls;-

- Number and Duration of Exposures;-

Rather than be exposed to heat for extended periods of time during the
course of a job, workers should, wherever possible, be permitted to
distribute the workload evenly over the day and incorporate work-rest
cycles.

- Provide cool rest areas in hot work environments to reduce the stress of
working in those environments. Shorter but frequent work-rest cycles are
the greatest benefit to the worker.

- Drinking Water

Most workers exposed to hot conditions drink less fluid than needed
because of an insufficient thirst drive. A worker, therefore, should not
depend on thirst to signal when and how much to drink. Instead, the
worker should drink 5 to 7 ounces of fluids every 15 to 20 minutes to
replenish the necessary fluids in the body.

- Protective Clothing
In dry climates, adequate evaporation of sweat is seldom a problem. In a
dry work environment with very high air temperatures, protective clothing
could be an advantage to the worker.

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 B- Chemical Hazards
- Exposure to cotton dust

 RISKs

- Byssinosis disease.

 SOURCEC

- dust present in the air during the handling or processing of cotton, which may
contain a mixture of many substances including ground up plant matter, fiber,
bacteria, fungi, soil, pesticides, non-cotton plant matter and other
contaminants which may have accumulated with the cotton during the
growing, harvesting and subsequent processing or storage periods.

 Control measures
* Engineering control;-

- Washing of cotton to prevent byssinosis washing leads to significant decline (up

to 95%) in endotoxins level in the airborne cotton dust. They concluded that
mildly washed cotton may lead to prevention of acute and possibly chronic
respiratory effects among exposed workers.
Although washing of cotton seems to be a promising option for prevention of
byssinosis, to date there is lack of clear evidence regarding two important
aspects: Whether this leads to prevention of chronic respiratory effects; and
more importantly how feasible it is for the textile industry.

- The bactericidal treatment of cotton before use. In this regard spraying of

benzododecinium bromide (a bacteriostatic chemical used for hand sanitation
and disinfection of medical instruments).

- Improved workplace design and machinery are other important sectors to be

considered. Dust control measures are possible at various stages in the
production and processing of cotton.

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- In the field factors that may affect the dust concentration include climatic
conditions, plant disease or pest infestations, use of chemicals, harvesting,
methods and mechanism for storage after harvesting.

- Use of lint cleaners has been found to reduce the amount of respirable dust in
the later processes.

- control methods at each stage of processing in the mills including automation

at the time of bale opening, enclosure at the time of bale opening and carding,
oil over spraying at the time of carding, humidifying at the time of spinning and
winding, and applying air cleaning devices at the time of winding

*Administrative controls;-

- Periodic medical examinations like spirometry, worker.

- Training and smoking cessation programmes.
- cleaning floors with a vacuum
- using mechanical methods to stack, dump or handle cotton.
- Checking, cleaning, and repairing dust control equipment and ventilation
systems.
- Conduct periodic measurements to conform to exposure limits (PEL) are average
exposures as measured over an 8-hour workday. For yarn manufacturing, the
limit is 200 micrograms of cotton dust per cubic meter of air; for textile waste
houses, 500 micrograms; for slashing and weaving operations, 750 micrograms;
and for waste recycling and garneting, 1000 micrograms.
- Employers must supply employees with respirators, if other measures are not
sufficient

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 C- Ergonomic issues
 RISKs

- Various occupational diseases. Musculoskeletal disorders like carpal tunnel

syndrome, forearm tendinitis, bicapital tendinitis, lower back pain,
epicondylitis, neck pain, shoulder pain, and osteoarthritis of the knees.

 SOURCEC

- Material handling.
- repetitive movements
- forceful movements
- Improper design of work station, tools and equipments.

 Control measures
1- Eliminates heavy lifting by operators or bundle boys.
2- Use pre- programmed hanging conveyor.
3- Moves only one or few work pieces per hanger.
4- Computer control of-movement tracked by bar-cod hanger.
5- Delivers work to queue near worker.
6- Proper working procedure.

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 D- Accident factor
1- Mechanical and electrical hazards

 RISKs

- Accidents due to machinery (Amputation or crushing injuries).

- Electrical short circuit happens.
- Electric shock

 SOURCEC

Each piece of machinery may have sources of energy (electrical, mechanical,

pneumatic, hydraulic, inertial and so on)

 Control measures:-

* Engineering control;-

- Adequate guarding should be fitted to prevent amputation or crushing

injuries.

- All circuits to be enclosed in a proper circuit

*Administrative controls;-

- Guarding of the multiplicity of moving parts and the rotors operate at

high speed and covers should not be removed until they have come to
rest. Where interlocking guards are fitted, they should prevent contact
with the blades until they have completely stopped.

- Training of operators in safe practices is essential, in particular to avoid

attempting repairs while the machinery is in motion, the cause of many
of the accidents.

- The facility should identify energy sources, provide necessary equipment

and train personnel to ensure that all hazardous energy sources are
turned off while working on equipment.

- An inspection should be performed on a regular basis to ensure that all

lockout/tag out procedures are being followed and correctly applied.

- PPE
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2- Fire and explosion hazards

 RISKs

- Burns injuries.

- Death.

- Destruction of installations and equipment.

- Loss of products.

 SOURCEC

- The presence of highly flammable materials such as cotton and YARN

THREAD Products are stacked next to machines.
- Short circuit happens.
- Improper earthing
- Friction between moving parts (wear &tear of machine – material
collision).
- Smoking.
 Control measures:-

* Engineering control;-

- Fire hydrant system and sprinkler system.

- Fire alarm.

- Storage areas should include safe places in the open air or a fire resisting
store.

*Administrative controls;-

- Cleanliness is essential to prevent accumulations in the workrooms.

- Stocks of such liquids should be reduced to a minimum in the workroom

and stored in a safe place when not in use.

- Designate special places for smoking

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