Guidelines on the Prevention of Lumbago in the Workplace (1994)
Ministry of Labour
Labour Standards Bureau Notification (Kihatsu) No.547,
Sep. 6, 1994
In
Japanese
|
| 1. |
Introduction
|
|
A number of workers have been suffering from lumbago while
working not only in specific types of work but in other types of operations
as well.
The main causes for the occurrence of lumbago can be attributed
to various factors, or their combinations, including:  1 movement factors
causing excessive static or dynamic burdens on the waist, 2 environmental
factors such as vibrations exerted on the waist, coldness or falling on
the floor or stairs; 3 individual factors such as age, gender, body or muscle structure, as well
as previous illness including hernia of an intervertebral disk or , underlying
diseases or mental stress.
Accordingly, the prevention of lumbago in the workplace requires
the carrying out of proper work control, working environmental control,
health management and industrial health education.
Workplaces should adopt measures suitable for their working
conditions on the basis of fundamental steps for the prevention of lumbago
listed in these guidelines.
These guidelines first indicate general preventive measures,
followed by basic measures by work type to the following five operations
that cause lumbago to a significant number of workers:
|
|
(1) |
operations requiring handling heavy objects; |
|
(2) |
operations involved with the providing of care in facilities
for seriously handicapped children; |
|
(3) |
operations involving standing while carrying an excessive burden
on the waist; |
|
(4) |
operations involving sitting in a chair or on the floor while
carrying an excessive burden on the waist; |
|
(5) |
operations involving driving a vehicle for long hours.
|
| 2. |
Work Control
|
|
(1) |
Automation and Labour Saving |
|
|
The basic measure for operations that may involve the carrying
of an excessive burden on the waist is to reduce that burden by automation
and mechanization of work processes. Introducing supplemental devices is
recommended if such automation/rationalization is difficult. |
|
(2) |
Working Posture and Movement |
|
|
It is necessary for workers to take the following precautions: |
|
|
a) |
Avoid unnatural postures that can cause increased burden on
the waist, including half-sitting, twisting, or wrenching while leaning
frontward or backward. For this end, adjust the height of working tables
and angles between workers and the working table so that they can position
themselves in front of the table. Use appropriate supporting stools, etc.,
if the worker has to maintain unnatural postures. |
|
|
b) |
Avoid sustaining the same position for a long period of time
when standing or sitting in a chair. |
|
|
c) |
Maintain a good posture and avoid sudden moves when such moves
can cause an increased burden on the waist. |
|
|
d) |
Make lifting, pulling, or pushing movements with knees slightly
bent, breathing properly and with the abdomen tensed. |
|
|
e) |
Avoid sudden twisting of neck or waist as far as possible,
and shift your eyesight to the movement. |
|
(3) |
Operation Standards, Etc. |
|
|
a) |
Establishing operation standards:
For types of work that may exert excessive burdens on the waist,
operation standards that consider the prevention of lumbago must be established
in the workplace by taking the following precautions. Reexamine these operation
standards when new devices or facilities are introduced to workplaces. |
|
|
|
(a) |
Working house, work load, working procedures, machinery and
tools, etc., should be indicated. In establishing working hours, load,
etc., consideration is necessary for the nature of the work, the weight
of objects handled, the degree of automation, supplemental devices, number,
gender, physical strength, age and experience of workers involved in specific
assignments. |
|
|
|
(b) |
Precautions are necessary not to force workers to be continuously
engaged in a specific type of work which requires an unnatural or repetitive
work postures by alternating such work with other types of work. It is
desirable to provide workers with suitable rest time during working hours. |
|
|
b) |
Other |
|
|
|
(a) |
Select an appropriate working speed, when the speed of operations,
e.g. that of conveyers is set mechanically, by considering the physical
strength and characteristics of the workers involved. |
|
|
|
(b) |
Set schedules for nighttime, shift or irregular work so that
work loads do not exceed those in daytime work. |
|
(4) |
Rest Facilities |
|
|
a) |
Provide workers with rest facilities providing adequate space
in which they can take rest by lying down if they are engaged in work that
may exert a considerable burden on the waist. |
|
|
b) |
I t is desirable to adjust the temperature in the rest
facility so that muscular tension can be relaxed. |
|
(5) |
Other |
|
|
a) |
Provide workers with appropriate supplemental devices, including waist
belts, if they are engaged in work that may exert considerable burdens
on the waist. |
|
|
b) |
Provide workers with working shoes suitable to their feet. Do not allow
the use of high-heeled shoes or sandals if they are engaged in work that
may exert considerable burdens on the waist.
|
3. Working Environmental Control
|
|
(1) |
Temperature |
|
|
Maintain an appropriate temperature for indoor workplace. In
a workplace involving low temperatures, it is desirable to provide workers
with warm clothing and suitable heating facilities. |
|
(2) |
Lighting |
|
|
Maintain good lighting conditions to allow a clear vision of
workplaces, corridors, stairs, and machines. |
|
(3) |
Work Floor |
|
|
The work floor should be as flat as possible, with adequate
non-slip, anti-shock and elastic properties as well as flexibility. |
|
(4) |
Work Space |
|
|
Maintain an adequate work space so as not to disturb the free
movement of workers. |
|
(5) |
Facility Location |
|
|
The format, dimensions and location of work facilities or tables
shall be determined from an ergonomics point of view by considering movements
and postures relating to the work.
|
4. Health Management
|
|
(1) |
Medical Examination |
|
|
Periodic medical examinations for lumbago before placement
(including reassignment; this also applies hereinafter) and every six months
thereafter are required for workers who are regularly engaged in operations
that can exert a significant burden on the waist, including operations
involving the handling of heavy objects, care provision, etc. |
|
|
a) |
Medical examination before placement |
|
|
|
Workers should undergo medical examinations on the following
items before their placement to better understand their health and establish
the results of such examinations as basic data for proper health management. |
|
|
|
(a) |
Survey of past medical and occupational records (especially
records on lumbago and treatment process) |
|
|
|
(b) |
Checkup of subjective symptoms (lumbago, melosalgia, myodynamic
degradation in lower limbs and perception disturbance) |
|
|
|
(c) |
Test of spinal column: abnormal postures, spinal column deformation,
mobility and tenderness of spinal column, tension and tenderness of lumbodorsal
muscle, and tenderness of acanthi |
|
|
|
(d) |
Neurological test: neurectasia test, deep tendon reflex, perception
test and amyotrophia test |
|
|
|
(e) |
Spinal column function test: Clause and Weber test or its
variation (functional test of abdominal or back muscles) |
|
|
|
(f) |
X-ray test of lumbar: two directions, standing position in
principle (if determined necessary by physician) |
|
|
b) |
Periodic medical examinations |
|
|
|
(a) |
Periodic medical examinations for lumbago should be carried
out on the following items: |
|
|
|
|
a. |
Survey of past medical and occupational records (especially
records on lumbago and treatment process) |
|
|
|
|
b. |
Checkup of subjective symptoms (lumbago, melosalgia, myodynamic
degradation in lower limbs, perception disturbance) |
|
|
|
(b) |
If determined necessary by physician as a result of examinations
specified in Item a. above, additional examinations should be carried out
on the following items. These examinations should be carried out in succession
to those in Item a. |
|
|
|
|
a. |
Test of spinal column: abnormal postures, spinal column deformation,
mobility and tenderness of spinal column, tension and tenderness of lumbodorsal
muscle, and tenderness of acantha |
|
|
|
|
b. |
Neurological test: neurectasia test, deep tendon reflex, perception
test and amyotrophia test (add tests relating to psychogenic factors, if
necessary) |
|
|
|
|
c. |
X-ray test of lumbago: if determined necessary by physician |
|
|
|
|
d. |
Motorial function test: if determined necessary by physician |
|
|
c) |
Post-examination measures |
|
|
|
As a result of lumbago examinations, necessary measures should be taken for the maintenance of worker health, including the improvement of working methods and the reduction of working hours. |
|
(2) |
Exercises Before Starting Work and for Lumbago Prevention |
|
|
a) |
Exercises before starting everyday work:
Exercises should be done by workers before starting each work session for the maintenance of health and the prevention of lumbago. |
|
|
|
(a) |
Limber up before starting work. |
|
|
|
(b) |
Stretch lower limbs before performing a specific work that can exert a
significant burden on the waist. |
|
|
|
|
Additional exercise should be done after completing such work
to relax muscular tension. |
|
|
b) |
Specific exercises for lumbago prevention: |
|
|
|
Specific exercises for lumbago prevention should be done by
workers engaged in operations such as the handling of heavy objects, care
provision, etc., exerting a significant burden.
These exercises include 1 stretching of joints; 2 stretching
of soft organs and 3 muscle rebuilding, which should be selected for
specific purposes.
|
5. Industrial Health Education
|
|
(1) |
Industrial Health Education |
|
|
Industrial Health Education for lumbago prevention should be
provided for workers who are regularly engaged in work that can exert a
significant burden on the waist, including the handling of heavy objects,
care provision, etc., when they are assigned to such work or as necessary.
Such education should be carried out on the following items in a way suitable
for their level of knowledge and experience: |
|
|
1 |
information on lumbago, |
|
|
2 |
improvement of working environment, working procedures, etc., |
|
|
3 |
how to use supplementary tools, and |
|
|
4 |
exercises before starting work and exercises for the prevention of lumbago. |
|
|
5 |
A lecturer of the said education shall be one who has a sufficient knowledge and experience in the prevention of lumbago. |
|
(2) |
It is indispensable for the prevention of lumbago to maintain
and improve the health of workers in their daily lives, in addition to
the promotion of necessary preventive measures in workplaces. Accordingly,
it is desirable to provide workers with appropriate guidance on well-balanced
meals, adequate sleep and other daily precautions under the direction of
industrial physicians, based on the understanding of employees' health
and physical strength. |
|
|
(Attachment) Measures by Work Type
|
| I. |
Operations Involving the Handling of Heavy Objects
|
|
It is necessary to take the following measures for workers
involved in handling heavy objects, in addition to observing specified
limitations for weight of objects handled, considering work concentration
such as frequency of handling per day, setting appropriate working hours
and allocating workers properly.
|
|
1. |
Automation and Labour Saving
|
|
|
(1) |
In principle, reduce work loads to be handled manually as much as possible by automation and rationalization of work processes when handling heavy objects. If the adoption of automation is difficult, use appropriate devices and tools to reduce such work loads. |
|
|
(2) |
If work loads still require manual handling, reduce excessive burdens exerted on the waist by adjusting work speed and the weight of objects handled.
|
|
2. |
Weight of Heavy Objects Handled
|
|
|
(1) |
The weight of objects handled manually by a male worker of 18 years of age or older shall be 55kg or less. Reduce the weight of heavy objects handled manually to not more than 40 percent of the weight of the worker regularly engaged in the manual handling of such heavy objects. |
|
|
(2) |
If heavy objects with a weight exceeding that specified in Item(1) above are handled, it is desirable that such objects be handled by two or more workers, in which case the burden should be shared equally by these workers.
|
|
3. |
Improvement of Cargo Packaging and Indication of Weight
|
|
|
(1) |
Consider packaging to make a pack compact. Pack articles with appropriate materials and provide a handle for easy handling. |
|
|
(2) |
Clearly indicate the weight on the packaging, if possible. |
|
|
(3) |
Clearly indicate the center of gravity if weight is unbalanced. |
|
|
(4) |
Use a hook, sling or other tools for easy handling.
|
|
4. |
Working Postures and Movements
|
|
|
Workers should be advised to take the following precautions.
In principle, avoid sudden body movements and minimize the
shift of the center of gravity when handling heavy objects so as not to
exert excessive burdens on the waist. Take note of the following points. |
|
|
(1) |
Handle heavy objects by approaching them as closely as possible with the lowered position. |
|
|
(2) |
Do not lift objects above the shoulder when loading or unloading
them. |
|
|
(3) |
When lifting objects from the floor, move a little one leg in front of the body, bend both knees, lift the objects in sitting-like posture, and extend the knees to stand up. |
|
|
(4) |
Use a work table of appropriate height for not bending the body. |
|
|
(5) |
Lift objects, taking a breath and tensing the abdomen. |
|
|
(6) |
Maintain a standing position with the back stretched while lifting an object.
|
|
5. |
Working Hours
|
|
|
(1) |
Working hours in which workers handle heavy objects should be reduced as much as possible by taking short rests and alternating such work with other types of operations, depending on actual working conditions, such as the weight of objects handled, the frequency of handling, distances and speeds of transport. |
|
|
(2) |
Specify the volume of objects to be handled during a unit working time to avoid excessive burdens on workers.
|
|
6. |
Others
|
|
|
Use a waist-protection belt, a supporter belt or other protective
devices to increase abdominal pressure.
|
| II. |
Operations to Provide Care in Facilities for Seriously Handicapped Children,
Etc.
|
|
When workers are engaged in providing care for children and
adults (hereinafter called "admitted children, etc.") in facilities
for seriously handicapped children, etc., they are often subject to excessive
static or dynamic burdens on the waist repeatedly or continuously, due
to operations performed in fixed postures or in half-sitting positions,
frequent shifts of weight and heavy work loads. Such working conditions
are often cited as a major cause of lumbago. It is recommended, therefore,
that work burdens be reduced by taking the following measures:
At the same time, it is desirable that facilities for physically
handicapped children or special nursery homes for the elderly take similar
measures to reduce the occurrence of lumbago.
|
|
1. |
Working Posture and Movements
|
|
|
Workers should avoid sustaining the same working posture for long periods of time when they have to work in a half-sitting positions or with bodies twisted into unnatural positions for a certain period of time. In such cases, short rests should be provided or other types of work should be alternated with said work. |
|
|
(1) |
Method of Care Provision |
|
|
|
Follow the guidelines in Section I, when admitted children,
etc., are lifted manually from the bed or the floor to provide care. More
than one person should be engaged in changing the position of heavy admitted
children etc., or moving them. |
|
|
(2) |
Assistance Methods for Meals |
|
|
|
Workers who assist admitted children, etc., in taking meals
should sit in a chair in front of the children or sit in the bed with the
child's head in their lap to avoid sitting on the bed with a posture that
involves twisting the body. Do not sustain the same posture for long.
|
|
2. |
Work Standards
|
|
|
Work standards should be set in accordance with devices or
working methods used. Work standards should include working processes based
on the physical conditions of admitted children, etc., and such processes
by type of work, role sharing and working places.
|
|
3. |
Appropriate Allocation of Care Workers
|
|
|
Ensure that an adequate number of care workers be assigned
in accordance with facility structure, working shifts, nature of care provision,
physical and mental conditions of admitted children etc.
If busy working conditions arise temporarily due to inevitable causes, do not allow specific types of work with a heavy burden on the waist to be concentrated in specific workers by reassigning care workers as required.
|
|
4. |
Improvement of Facilities and Structures
|
|
|
As improper facilities negatively affect the working posture
of workers, such facilities should be improved by introducing proper equipment
and devices for care provision and other related operations.
Furthermore, the following improvements should be made to ensure proper working posture by examining actual working conditions: |
|
|
(1) |
Room Structure |
|
|
|
Admitted children etc., should be moved using stretchers as
much as possible and obstacles to the movement of stretchers, such as difference
in levels, should be eliminated in passageways and rooms. |
|
|
(2) |
Bathtub Structure, Etc. |
|
|
|
a) |
The bathtub, body washing table, and shower should be designed to minimize unnecessary movements by care workers. |
|
|
|
b) |
The height of the bathtub, body washing table and shower should be adjusted to the physical conditions of care workers. Non-slip foot supports should be used by workers when the height of the bathtub, etc., is not adjustable for them. |
|
|
|
c) |
Movable body washing tables, body washing tables with roller conveyers, movable bathtubs, and lifts should be introduced. |
|
|
(3) |
Bed Structure, Etc. |
|
|
|
The height of the bed should be suitable for the height of care workers, and should give consideration to the physical condition of admitted children etc. Footwear and foot supports should be used by care workers for whom the bed height is not suitable. |
|
|
(4) |
Related Facilities |
|
|
|
Introduce chairs with backs or hard sofas for workers to sit and rest during care work. Keep equipment necessary for care provision in easily accessible locations. |
|
|
(5) |
Rest |
|
|
|
Comfortable and easy-to-use rest facilities should be installed by considering
the number of workers and their working shifts.
|
|
5. |
Other
|
|
|
Allow to use waist belts or supporters for workers in order
to increase abdominal pressure, as necessary.
|
| III. |
Operations Involving Standing While Exposing the Waist to Burdens
|
|
There are cases of standing work, such as assembling or service
provision, which can exert an excessive burden on the waist due to forward
bending or excessive stretching of the body stemming from strain in standing
positions or improper allocation of machines or working methods.
Take the following measures as necessary to eliminate the need
for such standing positions.
|
|
1. |
Allocation of Machines
|
|
|
Machines should be positioned to avoid forward bending or excessive
stretching of the body by considering the length of upper and lower limbs
and other physical features of the workers involved.
|
|
2. |
Alternating with Other Types of Work
|
|
|
Alternating standing work with other types of work, including
sitting work, is necessary to avoid sustained standing positions.
|
|
3. |
Position of Chairs
|
|
|
(1) |
When workers have to sustain standing positions for long periods, provide chairs to allow workers to rest. |
|
|
(2) |
Chairs should have adjustable-height and reclining backrests. Otherwise, provide suitable supplemental tools such as back-protective cushions. Ensure an adequate space between the seat surface and working table to allow the knees and toes of workers to move freely.
|
|
4. |
single footstools
|
|
|
Provide workers who are not required to use their legs for
work with a single footstool in accordance with their working postures.
|
|
5. |
Rest and Repose
|
|
|
Provide standing workers with one or two short rest periods
per hour in which they can perform knee bending exercises or massages.
|
|
6. |
Other
|
|
|
Allow the use of waist belts of back supporters for workers
in order to increase abdominal pressure, as necessary.
|
| IV. |
Operations Involving Sitting in a Chair or on the Floor While Exposing the Waist to Excessive Burdens
|
|
Generally speaking, less burden is exerted on the body of workers
when they are sitting in a chair or on the floor. On the contrary, however,
the burden on their lumbar is greater in the sitting position rather than
in the standing position. If in clerical work, office automation equipment
handling, customer contact job, or conveyer operations, workers sitting
in a chair or on the floor in forced strained positions or being limited
in their movements are engaged in bending, pulling or twisting objects,
they can be subject to an excessive burden on their waist. To avoid such
a burden, take the following measures.
|
|
1. |
Sitting Work in a Chair
|
|
|
(1) |
Improvement of Chairs |
|
|
|
Provide workers with a chair in which the height and depth
of the seat surface, the angle of the backrest, and the height of the armrest
can be adjusted in accordance with the worker's physical conditions and
consider body pressure distribution and the hardness of the seat surface. |
|
|
(2) |
Improvement of Working Table |
|
|
|
Use a working table in which the height, angle and distance
between the table and the chair can be adjusted. |
|
|
(3) |
Working Posture |
|
|
|
Workers should be advised of the following. |
|
|
|
a) |
Sit deeply in the chair with the waist adequately close to the backrest and the soles of feet firmly on the floor. Use a non-slip footstool if necessary. |
|
|
|
b) |
Maintain a space in which one's hand can be inserted between the chair and the lower thigh so as not to exert excessive pressure on the thigh. |
|
|
|
c) |
Keep an open space in which workers can move their knees and toes freely. |
|
|
|
d) |
Avoid forward-bending body position. Change body positions at proper intervals by standing up and stretching the back. |
|
|
(4) |
Working Area |
|
|
|
Limit working areas for sitting workers so as not to force
them to assume unnatural positions.
|
|
2. |
Sitting Work on the Floor
|
|
|
Avoid sitting work on the floor as much as possible because
an excessive burden can be exerted on the sacroiliac joint or coxa. Take
the following precautions for workers when they are forced to sit on the
floor while working due to inevitable conditions. |
|
|
(1) |
Do not sustain the same working posture for long periods and stand up to stretch the back in an appropriate manner. |
|
|
(2) |
When sitting with legs crossed, use a cushion under the lower back to lift up the bottom.
|
| V. |
Operations Involving Driving a Vehicle for Long Hours
|
|
Truck and vehicle-type construction machinery drivers are often
subject to an excessive burden on the waist because of the same posture
for long hours in the case of former and vibration on the waist in the
case of latter, thus causing lumbago. Moreover, cargo unloading work immediately
after driving is not desirable because it can lead to a temporary muscle
strength maladjustment, or inadequate peripheral blood circulation due
to forced postures during driving for long hours. Take the following measures
by considering these conditions:
|
|
1. |
Improvement of Seats, Etc.
|
|
|
(1) |
A driver's seat should be well adjusted for proper angle of
the seat surface and of the backrest as well as proper support by the backrest.
Before starting driving, ensure that the proper angle of the seat surface
and the backrest and the proper position of the seat are secured. |
|
|
(2) |
It is desirable to use vehicles that have a seat structure
which can reduce road vibration as much as possible.
If the adoption of such vehicles is difficult, use supplemental supports such as cushions, etc.
|
|
2. |
Short Rest
|
|
|
Take appropriate short rest breaks during vehicle driving operations.
Drivers should try to overcome fatigue from muscle contractions by stretching
exercises upon leaving the driver's seat during the short rest breaks.
|
|
3. |
Handling Heavy Objects After Vehicle Driving
|
|
|
Try to reduce burdens on workers stemming from handling heavy
loads by adopting vehicles with lifters or roller conveyers. Take measures
similar to those in Section I for the manual handling of heavy objects.
Carry out the handling of heavy objects after taking a short rest when drivers have to handle cargoes after driving for long hours.
|
|
4. |
Improvement of Facility Layout
|
|
|
In cargo transportation work by forklifts or in-company transport
vehicles that are operated within a company site, try to improve facility
layout to simplify vehicle routes and reduce work requiring left and right
turns or in narrow spaces.
|
|
5. |
Other
|
|
|
Allow the use of waist belts or back supporters for workers
in order to increase abdominal pressure, as necessary. |
|
|
top