Ch 15 Manual Material Handling

Question 1

What is Manual Material Handling (MMH)

Answer 1

the act of manual grasping and raising an object of a definable size without mechanical aids
- lifting, pushing, pulling, holding, carrying

Question 2

NIOSH lifting guidelines

Answer 2

3 components:

1. Recommended Weight Limit (RWL) - maximum weight of a lift considered safe given the conditions of the lift
2. Load Constant (LC) - max weight for a lift considered safe if the conditions are optimal
3. Multipliers - modifiers to LC that reduce what the RWL would be for certain conditions

Question 3

All 6 multipliers

Answer 3

Horizontal Multiplier - HM
Vertical Multiplier - VM
Distance Multiplier - DM
Asymmetric Multiplier - AM
Frequency Multiplier - FM
Coupling Multiplier - CM

Question 4

RWL Formula

Answer 4

LCHMVMDMAMFMCM

Question 5

inches to cm

Answer 5

1 inch = 2.5 cm

Question 6

HM formula

Answer 6

10/H = HM in inches

H = difference between the horizontal location of the hands (load center) and the midpoint between the ankles

If H cannot be measured:
- if V >= 10inch : H=8+L/2
- if V < 10inch : H=10+L/2

L = width of the container in plane perpendicular to shoulders
V = vertical location of hands at the origin of the lift from the floor

measured at origin and destination

Question 7

VM formula

Answer 7

1- .0075|V-30| = VM in inches

V: vertical location of the hands from the standing surface

Measured for origin and destination

Question 8

DM formula

Answer 8

0.82 + 1.8/|D| = DM in inches

D: vertical travel distance between the location of hands at origin and destination of lift
- D = Vdestination - Vorigin
- Note: if D < 10inches, DM = 1

Measured for origin and destination

Question 9

AM formula

Answer 9

1-.0032A

A:angular displacement of load from sagittal plane

Should be measured at end or beginning based on which has the greatest angle

Question 10

CM formula

Answer 10

CM = 1, if handles, cutouts, or ability to wrap around load
CM = 0.90, if irregular loose or bulky
CM = 0.95, if no handles or cutouts but can flex fingers 90 degrees and V < 30inch
- if v >= 30 inches, CM = 1

Question 11

Lifting Index (LI)

Answer 11

Load lifted / RWL

If LI <= 1, then acceptable
If LI > 1, not acceptable

Question 12

If LI > 1 and <1.5

Answer 12

risk implication: low
- attention required for low frequency / high load conditions

Question 13

If LI > 1.5 and <2

Answer 13

Risk: moderate
- redesign needed

Question 14

If LI > 2 and <3

Answer 14

risk High
- Change needed

Question 15

If LI > 3

Answer 15

risk very high
- urgent