NIOSH LIFTING EQN.-ppt

SAMPLE CALCULATION
The measured task variables when the worker is lifting:-

Load to be lifted= 20Kg

H1(origin)= 40cm V1(origin)= 50cm A1(origin)=0

H2(dest.) = 43cm V2(dest.) =0 A2(dest.) =0

D(dist.)= 50cm F (freq.) = 4 Duration (hrs) =1-2

C(coupl.) = Poor

FOLOWING ARE THE
MULTIPIERS:-
AT ORIGIN

HM= 25/H=0.63

VM= 1-(0.003|V-75|)=092

DM=0.82(4.5/D)=0.91

AM=1-(0.0032A)=1

FM (from table)=0.72 CM(from table)=0.9

AT DESTINATION

HM= 25/H=0.58

VM= 1-(0.003|V-75|)=0.78

DM=0.82(4.5/D)=0.91

AM=1-(0.0032A)=1


RESULTS
RWL=LC * HM *VM * DM * AM *FM * CM

RWL(origin)=7.8Kg
RWL(dest.) = 6.1Kg

LI(origin)= Load/RWL=2.6
LI(dest.) =Load/RWL =3.3

As the Lifting Index is more than one which indicates
that the worker must be having problem of Low Back
Pain, thus the layout is to be redesigned by redesigning
the task variables

REVISION OF THE UNSAFE
RESULTS

THE RESULTS OBTAINED FOR THE
ABOVE SAMPLE ARE UNSAFE. THUS
WORKING LAYOUT IS REVISED BY
REVISING THE TASK VARIABLES IN
ORDER TO HAVE THE SAFER RESULTS
i.e SAFE LOADING CONDITIONS OF THE
WORKER.

SAMPLE CALCULATION
The revised task variables when the worker is lifting:-
AT ORIGIN

Load to be lifted= 20Kg

H1(origin)=30cm V1(origin)=50cm A1(origin)= 0

H2(dest.) = 30 cm V2(dest.) =40 cm A2(dest.) =0

D(dist.)=10 F(freq.) =3 Duration(hrs)=1-2

C(coupl.)=Poor

AT DESTINATION

HM= 25/H=0.58

VM= 1-(0.003|V-75|)=0.9

DM=0.82(4.5/D)=1

AM=1-(0.0032A)=1


REVISED RESULTS
RWL=LC * HM *VM * DM * AM *FM * CM

RWL(origin)=12.6Kg
RWL(dest.) =12.2Kg

LI(origin)=Load/RWL=1.5
LI(dest.) = Load/RWL=1.6

As the Lifting Index is not less than one ,but the
layout of work has been revised so as to reduce the LI
to maximum possible extent. Thus summarising the
revisions made as mentioned:

CHANGES DONE IN THE TASK
VARIABLES
 The worker is advised to be closer to the Origin and
destination points in order to increase the HM

 Raising the height of the Destination Point in order to
increase VM

 Reducing the lifting frequency in order to increase the FM

 Further the LI can also be reduced by reducing the Load to
be lifted

SOFTWARE DEVELOPED
FEATURES

 The software has been made in C++ Programming
Language.
 It is used to calculate the RWL & LI using NIOSH
Lifting Equation.
 The input given to the software are the values of Task
Variables.
 The output comprises of the Multipliers along with
RWL & LI.

Start

Define variables
involved

Initialize desired
variables

Define various functions

A
Read input
data i.e task
variables

Call functions for task
multipliers
B

B

NO
NO
If Dur==1 If Dur==2 If Dur==3

YES
YES
YES

Call function for freq.
multiplier for V1

NO
NO
If Dur==1 If Dur==2 If Dur==3

YES
YES
YES

Call function for freq.
multiplier for V2

C

C

NO

A Display all the
multipliers

Compute RWL and LI

Display RWL and LI

NO
End

YES

Stop

THE RESULTS
ALONG WITH THE
EXECUTION OF THE
PROGRAMME

16

Enter the following data
Load to be lifted---
15
Horizontal Distance at origin---
50
Horizontal Distance at Destination---
45
Vertical Distance at Origin---
114
Vertical Distance at Destination---
0

Frequency i.e, Lifts per Minute---
3
Asymmetric Angle at Origin---
15
Asymmetric Angle at Destination---
20
What is the type of Coupling
PRESS
1 for Good
2 for Fair
3 for Poor
2

What is the Duration of Service
PRESS
1 for <=1 hour
2 for 1 to 2 hours
8 for 2 to 8 hours
2
---------------------------------------------
The Recommended Weight Limit(RWL1) at origin is
6.563798
----------------------------------------------
The Recommended Weight Limit(RWL2) at Destination is
5.97883

---------------------------------------------
The lifting Index at origin is 2.285262
----------------------------------------------
----------------------------------------------
The lifting Index at Destination is 2.508852
----------------------------------------------
MULTIPLIERS ARE AS UNDER
HM VM DM AM FM CM
0.50.8830.8594740.9520.791

0.555556 0.775 0.859474 0.9360.79 0.95

NIOSH LIFTING EQN.-ppt

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