|
Key Concepts:
- Electrocution
Hazards
- Caught-In, Compressed
or Crushing Hazards
- Struck-By Hazards
- Other Hazards
Controlling the Problem:
- OSHA power line
clearance distances.
- ANSI requirements
for working around power lines.
- Safe working
clearance distance for cranes.
- Preventive measures
for avoiding power line contacts.
- Planning for
power line hazards.
- Dealing with
power line emergencies.
| Weather
|
Sunny,
Clear |
| Competent
Person On-Site? |
Yes
- Victim |
| Safety
Program? |
No |
| Inspections
Conducted? |
Yes
|
| Training
Provided? |
No |
| Experience
of Victim |
4
Months |
| Time
on Project |
4
Hours |
| Weather
|
Clear/Dry |
| Competent
Person On-Site? |
No |
| Safety
Program? |
Yes |
| Inspections
Conducted? |
No |
| Training
Provided? |
No |
| Experience
of Victim |
5
Years |
| Time
on Project |
1
Day |
Current can flow outward
through ground in a ripple pattern from the equipment in contact with a
power line.
- Name two (2)
requirements about power line safety?
- Name four (4)
things a contractor can do to prevent a power line contact?
- If a contractor
contacts a power line, what are some things that either the operator
or workers around the crane can do to prevent electrocution.
- What minimum
power line clearance does OSHA require when operating a crane near these
power lines?
- 12kV power line_______feet
- 134kV power line______feet
-
Swinging superstructure
of equipment.
- Exposure to moving
parts.
| Weather |
Clear/Cool |
| Competent Person
On-Site? |
No |
| Safety Program?
|
No |
| Inspections
Conducted? |
No |
| Training Provided? |
No |
| Experience of
Victim |
Unknown |
| Time on Project
|
4 Days |
- Hazards associated
with being caught-in, compressed or crushed while working around cranes
and other material handling equipment include:
- What can contractors
do to prevent anyone from being crushed by the swinging superstructure
of a mobile crane or other material handling equipment?
-
Falling or failing
loads
- Swinging loads
To effectively manage
the safe rigging and hoisting of loads, ensure:
- A qualified rigger
oversees all lifting operations.
- All rigging devices
are used properly and are in good condition.
- Main hoisting
line has been inspected, properly installed and maintained.
- Pre-critical
lift evaluation performed (if applicable).
VIOLATION
Weather
|
Clear
|
| Inspections
Conducted? |
Yes |
| Competent
Person On-Site? |
Yes
|
| Safety
Program? |
Yes |
| Training
Provided? |
Yes |
| Time
on Job |
1
Hour |
| Time
on Task |
1
Hour |
- Know the Weight
- Know the Capacity
- Retain the Load
- Control the Load
| Weather
|
Clear
|
| Inspections
Conducted? |
Yes |
| Competent
Person On-Site? |
Yes |
| Safety
Program? |
Yes |
| Training
Provided? |
Yes |
| Experience
of Victim |
6
Months |
| Time
on Project |
2
Hours |
The following is a discussion
on:
- Shackles
- Hooks
- Wire Rope Clips
- Wedge Sockets
- Eyebolts
- Spreader Beams
- Slings
|
Recommended
|
Not
Recommended
|
Recommended
|
Never replace a shackle
pin with a bolt.
The load will bend the bolt.
Check with manufacturer for specifications on Side Loading.
120 degree max.
Avoid eccentric loads.
Proper chocking of shackles.
- Manufacturers'
identification.
- Never weld on
hooks.
- Working safety
latch.
Hooks are designed to
apply the load at the bottom of the saddle.
- The most common
use of wire rope clips on cranes is at wedge and socket-end fittings.
- The clip does
not provide strength to the wedge and socket connection.
- It is there to
prevent the wedge from accidentally being released.
Installed properly
as to number, direction, spacing and torque.
- Most common method
of terminating ropes on cranes.
- All parts must
match in size.
- Measure rope
diameter to ensure proper size.
- Live end of the
rope, the straight side of the socket and the pinhole all line up.
- May be necessary
to beat the socket during installation.
- Socket may become
mushroomed.
- Replace when
damage becomes noticeable.
This type of wire rope clip (single grip, single saddle) will transfer the
weight of the load to the dead end of the load line.
Attach the wedge socket directly to the load ball without the use of a shackle.
VIOLATION
Always load an eyebolt in the plane of the eye.
- Marked with the
capacity and proof tested to 125 percent of that capacity.
- Considered a
load and cannot be left suspended unattended.
Spreader Beam
Equalizer Beam
The following is a discussion
on:
- Sling angles
- Sling tension
- Various types
of hitches
- Various types
of slings
- Inspections and
maintenance
Note:
A good operating practice is to keep sling angles from going below 60
degrees
Riggers and operators
should know how to determine the sling tension based upon knowing:
- Sling angle factor
- Total weight
of the load
- Number of legs
in the hitch
Sling Angle Factor =
L/H
Where:
L = Length of the sling.
H = Height of the connection point from the horizontal plane of the load.
Straight Pull
Choker Hitch (Horizontal Angle )
Basket Hitch
D:d Ratio
D - is diameter around which sling is bent.
d - is diameter of the sling.
Quadruple Leg Slings
Reach = a + b
Single Leg Slings
- Chain Size
- Manufacturers
Grade
- Rated load and
angle
- Reach
- Number of legs
- Manufacturers
name and trademark
- Next inspection
Frequent
- Visual examination
by the user.
Periodic
- Complete link
by link inspection of the entire sling and all attachments.
- Documented
- Twists or bends
- Nicks or gouges
- Excessive wear
at bearing points
- Stretch
- Distorted or
damaged master links
Wire Rope
Components
One complete wrap of
a strand around the core
The direction the strands are wound around the core
Right Lay
 Left Lay
Right Regular Lay
Right Lang Lay
Non-Mandatory
- Rated Load (rated
capacity)
- Load test date
- Manufacturer's
name
- Periodic inspection
due date
- Broken wires
(10 in one lay or 5 in one strand)
- Severe corrosion
- Localized wear
- Reduction in
outer wire
- Damaged end fittings
- Distortion, kinking,
etc...
Note:
If any of these conditions exist, the wire rope sling must not be used.
Broken Wires
Wire Rope Abuse
Wire Rope "Bird Caging"
- Field lubrication
- Storage
- Termination
Note:
Using the sling several times a week, even at a light load, is a good practice.
Records show that slings that are used frequently or continuously give useful
service far longer than those that are idle
Fiber Rope
- Manila
- Grip load well
and does not mar the surface.
- Not used around
sharp edges or in hot environments.
Synthetic
- Web Nylon, polyester,
dacron and polypropylene.
- Grip load well
and does not mar the surface.
- Can take sharp
edges better than fiber rope but stills needs to be protected.
- Name or trademark
of manufacturer.
- Manufacturers'
code or stock number.
- Rated loads for
the types of hitches used.
- Type of natural
or synthetic materials.
- Date of manufacturer.
Fiber rope and synthetic
web slings must be removed from service if any of the following defects
exist:
- Cuts
- Worn surface
- Fiber breakage
- Discoloration
- Melted or charred
- Pitting or corrosion
- Installed
- Correctly Inspected
- Maintained
Frequent
- Daily visual
inspection.
- Observe rope
during day's operations.
Periodic
- Determined by
a qualified person.
- Based on rope
life, severity of environment, percentage of capacity lifts, frequency,
shock loads.
- Six randomly
distributed broken wires in one lay or three broken wires in one strand
in one lay.
- Kinking, crushing,
birdcaging, or any other damage.
- More than two
broken wires in one lay section beyond end connections.
- Hand placement
on and around suspended loads
- Traveling with
the load
- Working in close
proximity
- Making "blind
picks"
This worker is at great
risk of becoming off balance and could easily fall off the roof. Fall protection
is required for this type of work.
- Evaluate prevailing
conditions
- Determine applicable
safety precautions
- Check with crane
manufacturer
When performing pick
and carry operations, travel towards the load.
- Do not ride on
the machine
- Crane should
be lowered
- Check tire pressure
- Avoid sudden
starts and stops
- Use tag lines
- Use a helper
during "pick and carry"
- Hazards of being
struck-by a falling or flying object while working around cranes and
other material handling equipment include what two (2) things?
- What four (4)
things should take place in order to effectively manage the safe rigging
and hoisting of loads?
- Which sling(s)
require written record of inspection?
- Use the diagram
provided to determine the sling angle factor and tension in each sling.
- Environmental
hazards
- Performing critical
lifts
- Using a crane
suspended personnel platform
- Lifting a load
with multiple cranes
- Mobile cranes
mounted on barges
- Protection from
exhaust pipes
- Asphyxiation
Hazards
Working During Inclement
Weather (High Winds):
- Procedures to
responding to high wind alerts
- Procedures to
coordinate with other cranes
- Procedures for
securing cranes in high winds
Working During Inclement Weather
(Lightning & Thunderstorms)
Defined as:
- Potentially unacceptable
risk of personnel injury or property damage
- Release of undesirable
conditions
- Undetectable
damage
- Significant work
delay
- OSHA & ANSI regulations
must be thoroughly reviewed.
- Requirements
for platform users and crane operators are reviewed.
- Pre-Lift meeting
must be held.
- Rated load must
not exceed original capacity.
- Crane must be
positively secured.
- Meet manufacturers'
requirements.
- To keep a crane
from toppling over during high winds and thunderstorms, what three (3)
things can you do?
- What four (4)
conditions may turn an ordinary lift into a critical lift?
- What four (4)
general safety rules apply to crane operators when lifting personnel
with a crane suspended personnel platform?
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