- Record Type: Instruction
- Directive Number: CPL 2-1.29
- Subject: Interim Inspection Procedures During
Communication Tower Construction Activities.
- Information Date: 01/15/1999
| DIRECTIVE NUMBER: CPL 2-1.29 |
EFFECTIVE DATE: January 15,
1999 |
| SUBJECT:Interim Inspection Procedures
During Communication Tower Construction
Activities |
ABSTRACT
| Purpose: |
This instruction describes OSHA's inspection
policy and procedures to ensure uniform enforcement by field
enforcement personnel of the provisions addressing fall
protection and safe access to communications towers during
construction. |
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| Scope: |
OSHA-wide |
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| References: |
Construction Safety and Health Standards, Subpart E, 29
CFR 1926.550 and Subpart M.
American National Standard, ANSI - B30.7, Base Mounted Drum
Hoist
Michigan Department of Consumer and Industry Services
(MIOSHA) interim order from rule R408.4113(1), Rule
1113(1).
National Association of Tower Erectors (NATE) Guidelines
for the Radio, Television, Communications Tower Industry.
ANSI/TIA/EIA-222-F-1996, Structural Standard for Steel
Antenna Towers and Antenna Supporting Structures.
Occupational Safety and Health Act of 1970, Section
5(a)(1). |
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| State Plan Impact: |
This instruction describes a Federal Program Change for
which State adoption is not required but notice of State
intent must be provided.
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| Action Offices: |
National, Regional, and Area Offices. |
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| Originating Office: |
Directorate of Construction |
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| Contact: |
Mark Hagemann (202) 693-2345 Directorate of
Construction 200 Constitution Ave., N.W., Room
N3621 Washington, DC 20210
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By and Under the Authority of Charles Jeffress Assistant
Secretary, OSHA
TABLE OF CONTENTS
- Purpose
- Scope
- Application
- Action
- Federal
Program Change
- Background
- Compliance
Guidelines for Fall Protection and Employee Access by Hoist During
Communication Tower Construction Activities
- Citation
Guidelines
APPENDIX
A COMPLIANCE GUIDELINES FOR EMPLOYEE ACCESS BY HOIST DURING
COMMUNICATION TOWER CONSTRUCTION ACTIVITIES
Definitions Specific Requirements
- Training
- Equipment
- Trial Lift and Proof Testing
- Pre-Lift Meeting
- Documentation
- Hoisting an Employee to the Work Station
- Communication Between the Hoist Operator and Hoisted
Employees
- Weather Conditions/Energized Power Lines
- Hydraulic Hoists (Drum Hoists)
- Hoist Mounting
- Drums
- Brakes and Clutches
- Hoist Controls
- Wire Rope and Rigging
- Hoist Operator
- Hoist Inspections
- Purpose. This instruction
establishes the inspection policy and procedures to ensure uniform
enforcement of the provisions addressing fall protection and safe
access to communications towers during construction and describes
best practices for use by the industry.
- Scope. This instruction applies
OSHA-wide.
- Application. This instruction
applies only to the construction of new communications towers.
Activities such as maintenance, retrofitting, and dismantling will
be addressed in a future directive.
- Action. Regional Administrators and
Area Directors shall ensure that compliance officers are familiar
with the contents of this instruction and that the enforcement
guidelines are followed. This instruction will be re-evaluated
after one year.
- Federal Program Change. This
instruction describes a Federal program change for which State
adoption is not required but notice of State intent must be
provided. States have 60 days from the date of this instruction to
provide their Regional Administrator a notification of whether the
State intends to adopt the procedures outlined in this
instruction. The notification should specify whether the State
intends to follow the guidelines contained in this instruction.
NOTE: In order to effectively enforce safety and health
standards, guidance to compliance staff is necessary. Although
adoption of this instruction is not required, States are expected
to have standards, enforcement policies and procedures which are
at least as effective as those of Federal OSHA. States may accept
employer compliance with the industry guidelines contained in this
instruction as providing the necessary protection for worker
access during tower erection.
[This Directive includes a Notification requirement because of
the alternative compliance methods allowed.]
- Background. Accessing towers by
the use of fixed ladders with attached climbing devices has been
the preferred method as it provides conventional fall protection
during ascent and descent of the structure. Some representatives
of the tower construction industry assert that continual climbing
of high towers is physically demanding and can lead to stress and
medical ailments over an extended period of time and may
contribute to other safety problems including falls. To alleviate
these problems, the industry has asked that employees be allowed
to ride a hoist line to work stations on towers. Since OSHA does
not specifically address tower erection under its current
standards but wishes to help reduce the accident and injury rates
associated with tower erection, OSHA believes that the methods in
Appendix A represent the best practices which can be implemented
to safeguard employees while being hoisted to work stations on the
tower. If new information shows that these practices need to be
changed, OSHA will revise this directive accordingly.
- Compliance Guidelines for Fall
Protection and Employee Access by Hoist During Communication Tower
Construction Activities.
- For purposes of this directive, OSHA agrees that the hoist
line may be used to hoist employees for access to tower work
stations over 200 feet in height if the work practices and
requirements set out in Appendix A are followed. At heights of
200 feet and below, employees may not be hoisted to their work
stations using the hoist line.
When climbing the tower during construction activities,
employees must be protected from falls using a fall arrest
system meeting the criteria of 1926.502 or a ladder assist
safety device meeting the requirements of 1926.1053(a). These
are acceptable methods of accessing tower work stations
regardless of height. All employees climbing or otherwise
accessing towers must be trained in the recognition and
avoidance of fall hazards and in the use of the fall protection
systems to be used, pursuant to 1926.21 or where applicable,
1926.1060.
- Some industry representatives have joined with OSHA in
recommending that each employee six feet or more above a lower
level should be protected from falling by a guardrail system,
safety net system, ladder safety device, fall arrest system or
positioning device system. However, current OSHA standards only
require fall protection at heights of more than 25 feet.
- Citation Guidelines
- For hazards associated with falls once employees are at
their workstation at levels in excess of 25 feet, employers who
fail to provide fall protection shall be cited under
1926.105(a).
- Whenever an employer fails to follow the guidelines set
forth in Appendix A, citations shall be issued under the
applicable provisions of subpart N and, in the alternative,
section 5(a)(1) of the Act (the general duty clause) for hazards
associated with work practices and equipment used to hoist
employees on load lines to gain access to towers.
APPENDIX A
Compliance Guidelines for Employee Access by
Hoist During Communication Tower Construction Activities
Definitions
Crew Chief: One who is authorized, designated,
deemed competent and qualified by the employer.
Anti-Two
Blocking: A positive acting device which prevents contact between
the load block or overhaul ball and the top block (two-blocking), or
a system which deactivates the hoisting action before damage occurs
in the event of a two-block situation.
Maximum Intended
Load: The total load of all employees, tools, materials, load lines
and other loads reasonably anticipated to be applied to the hoist
apparatus when an employee is hoisted.
Competent Person: One
who is capable of identifying existing and predictable hazards in
the surroundings or working conditions which are unsanitary,
hazardous, or dangerous to employees and who has authorization to
take prompt corrective measures to eliminate problems.
Authorized Person: A person approved or assigned by the
employer to perform a specific type of duty or duties or to be at a
specific location or locations at the job site.
Qualified:
One who, by possession of a recognized degree, certificate or
professional standing, or who by extensive knowledge, training and
experience, has successfully demonstrated the ability to solve or
resolve problems relating to the subject matter, the work or the
project.
Gin Pole: A device attached to the tower used to
raise sections of tower steel or equipment into position.
Specific Requirements. Employees may be hoisted on
the hoist line to reach work stations at heights greater than 200
feet only if all of the following conditions are met. The Agency
believes that strict adherence to the guidelines set forth in this
Appendix will provide employers with the appropriate safety measures
for access during tower erection. Riding the hoist line to work
stations at heights less than 200 feet is not permitted.
1. Training. Before an employee is allowed to
perform any job related to hoisting employees aloft for tower work,
the employee shall receive training on safe access pursuant to these
guidelines. The operator of the hoist shall have a thorough
understanding of these guidelines pertaining to hoisting employees
on the hoist line.
2. Equipment.
- An anti-two block device shall be used on all hoists, except
where an employer can demonstrate that ambient radiation frequency
(RF) precludes that use. In such case, a site specific program
will be established and maintained on site to ensure that two
blocking cannot occur and that effective communication between the
hoist operator and personnel being hoisted is maintained. This
program could include a cable marking system, an employee situated
on the tower in a position to observe the top block, or any other
system which will adequately ensure communication.
- The rigging, hoist line and slings shall have a factor of
safety of 10 against failure during personnel lift(s).
- The hoist line used to raise or lower employees shall be
equipped with a swivel to prevent any rotation of the employees.
- The use of spin-resistant wire rope is prohibited when
hoisting employees.
- When hoisting personnel (versus material) the hoist capacity
load rating shall be derated by a factor of 2 (reduced by half).
- All employees shall be provided with and required to use the
proper personal protective equipment (including fall protection
equipment) which shall be inspected before each lift.
- Except where the employer can demonstrate that specific
circumstances or conditions preclude its use, a guide line (tag
line) shall be used to prevent the employees or the platform from
contacting the tower during hoisting.
- The gin pole shall be thoroughly inspected before use by a
competent person to determine that it is free from defects,
including but not limited to: damaged and/or missing members;
corrosive damage; missing fasteners and broken welds at joints;
and general deterioration.
- The gin pole shall be attached to the tower as designed by a
registered professional engineer. There shall be a minimum of two
attachment locations: at the bottom of the gin pole and near the
top of the tower being erected.
- The personnel load capacity and material capacity of the
lifting system in use shall be posted at the site near the
location of the hoist operator. If the system is changed (for
example, if the gin pole angle is changed), the posted capacity
shall be changed accordingly.
3. Trial Lift and Proof Testing.
- A trial lift of the maximum intended personnel load shall be
made from ground level to the location to which personnel are to
be hoisted.
- The trial lift shall be made immediately prior to placing
personnel on the hoist line. The hoist operator shall determine
that all systems, controls and safety devices are activated and
functioning properly. A single trial lift may be performed for all
locations that are to be reached from a single set-up position.
The hoist operator shall determine that no interference exists and
that all configurations necessary to reach those work locations
remain under the limit of the hoist's rated capacity as identified
in paragraph 2(e), and additionally maintain a 10:1 factor of
safety against failure.
- The trial lift shall be repeated prior to hoisting employees
whenever the hoist is moved and set up in a new location or
returned to a previously used position.
- After the trial lift, employees shall not be lifted unless the
following conditions are met:
(1) Hoist wire ropes are determined to be free of
damage in accordance with the provisions of 29 CFR 1926.550;
(2) Multiple part lines are not twisted around each other;
and,
(3) The proof testing requirements have been
satisfied.
- If the hoist wire rope is slack, the hoisting system shall be
inspected to ensure that all wire ropes are properly seated on
drums and in sheaves.
- A visual inspection of the hoist, rigging,
base support and foundation shall be made by a competent person
immediately after the trial lift to determine whether testing has
exposed any defect or adverse effect upon any component of the
structure.
- Any defects found during the inspection which may create a
safety hazard shall be corrected, and another trial lift shall be
performed before hoisting personnel.
- Prior to hoisting employees and after any repair or
modification, the personnel rigging shall be proof tested to 125%
of the greatest anticipated load by holding it in a suspended
position for five minutes with the test load evenly distributed
(this may be done concurrently with the trial lift). After proof
testing, a competent person shall inspect the rigging. Any
deficiencies found shall be corrected and another proof test shall
be conducted.
4. Pre-Lift Meeting.
- A pre-lift meeting shall be held prior to the trial lift at
each location.
- The pre-lift meeting shall:
(1) be attended by the hoist operator, employees
to be lifted, and the crew chief;
(2) review the
procedures to be followed and all appropriate requirements
contained in this guideline; and
(3) be repeated for any
employee newly assigned to the operation.
5. Documentation.
- All trial lifts, inspections and proof tests shall be
documented, and the documentation shall remain on site during the
entire length of the project.
- The pre-lift meeting shall be documented, and the
documentation shall remain on site during the entire length of the
project.
6. Hoisting an Employee to the Work Station.
- Except where an employer can demonstrate that specific
circumstances or conditions preclude its use, a personnel platform
must be used to hoist more than one employee to the work station.
That personnel platform must meet the requirements of 29 CFR
1926.550 (g). When a personnel platform cannot be used, the
provisions in paragraph b below must be followed.
- When a boatswains seat-type or full body seat harness is used
to hoist employees, the following shall apply:
(1) No more than two employees may be hoisted at a
time;
(2) The employee's harness shall be attached to the
hook by a lanyard meeting the strength requirements of 29 CFR
1926.502;
(3) Only locking-type snap hooks shall be used;
and
(4) The harness shall be equipped with two side rings
and at least one front and one back D ring.
- The hoist line hook shall be equipped with a safety latch
which can be locked in a closed position to prevent loss of
contact.
- The maximum rate of travel shall not exceed 200 feet per
minute when a guide line is used to control personnel hoists. When
a guide line cannot be used, the rate of travel of the employee
being hoisted shall not exceed 100 feet per minute. In all
personnel hoist situations, the maximum rate shall not exceed 50
feet per minute when personnel being lifted approach to within 50
feet of the top block.
- The use of free-spooling (friction lowering) is prohibited.
- When the hoist line is being used to raise or lower
employee(s), there shall be no other load attached to any hoist
line, and no other load shall be raised or lowered at the same
time on the same hoist.
- As-built drawings approved by a registered professional
engineer shall provide the lifting capacity of the gin pole and
shall be available at the job site.
- The gin pole raising line shall not be used to raise or lower
employees.
- Employees must maintain 100% tie-off while moving between the
hoist line and the tower.
7. Communication Between the Hoist Operator and Hoisted
Employees.
- Employees being hoisted shall remain in continuous sight of
and/or in direct communication with the operator or signal person.
In those situations where direct visual contact with the operator
is not possible and the use of a signal person would create a
greater hazard for the person being hoisted, direct communication
alone, such as by radio, shall be used.
- When radios are used, they shall be non-trunking closed 2-way
selective frequency radio systems.
- When hand signals are used, the employees must use industry
standardized hand signals as required by 1926.550(a)(4).
8. Weather Conditions/Energized Power Lines.
- Employees shall not be hoisted during adverse weather
conditions (high winds, electrical storms, snow, ice, sleet), or
other impending danger, except in the case of emergency employee
rescue. This determination shall be made by the competent person.
- The hoist system (gin pole and its base hoists) used to raise
and lower employees on the hoist line, shall not be used unless
the following clearance distances as recommended by ANSI are
maintained at all times during the lift:
Power line voltage phase to phase (kV) |
Minimum safe clearance (feet) |
| 50 or below |
10 |
| Above 50 to 200 |
15 |
| Above 200 to 350 |
20 |
| Above 350 to 500 |
25 |
| Above 500 to 750 |
35 |
| Above 750 to 1,000 |
45 |
9. Hydraulic Hoists (Drum Hoists).
- The hoist used for personnel lifting shall meet the applicable
requirements for design, construction, installation, testing,
inspection, maintenance, modification, repair and operations as
referenced in this Appendix and as prescribed by the manufacturer.
Where manufacturers' specifications are not available, the
limitations assigned to the equipment shall be based on the
determinations of a registered professional engineer.
- The hoist shall be positioned so that it is level and the
distance between the drum and the foot block at the base of the
tower will allow proper spooling of wire rope.
- The foot block shall be anchored to prevent displacement and
be supported to maintain proper alignment.
- The hoist shall be designed to lift materials and personnel
with the same drum or drums.
- Any hoist that has been modified or repaired must be
proof-tested to 125% of its rated capacity.
- Rated load capacities, recommended operating speeds, and
special hazard warnings or instructions shall be conspicuously
posted on all hoists.
- Belts, gears, shafts, pulleys, sprockets, spindles, drums, fly
wheels, chains or other rotating parts, where exposed, shall be
totally enclosed.
- Personnel load capacity for the current configuration of the
gin pole shall be posted within sight of the hoist operator.
- The hoist shall have an hour meter and a line speed limiter.
- The hoist shall be designed for and must use powered lowering.
- The alignment of hoist components shall be maintained within
manufacturer's specified limits that prevent premature
deterioration of gear teeth, bearings, splines, bushings, and any
other parts of the hoist mechanism.
- All exhaust pipes shall be guarded where exposed.
- An accessible fire extinguisher of 5BC rating or higher shall
be available at the operator's station.
- The hoist shall be serviced and maintained per the
manufacturer's recommendations.
- The operating manual developed by the manufacturer for the
specific make and model hoist being used shall be maintained at
the site at all times.
- A hoist log book shall be used to record all hoist
inspections, tests, maintenance and repair. The log shall be
updated daily as the hoist is being used and shall be signed by
the operator and/or crew chief. Service mechanics shall sign the
log after conducting maintenance and repair. The log shall be
maintained at the site.
10. Hoist Mounting.
- The hoist shall be installed following the manufacturer's
mounting procedure to prevent excessive distortion of the hoist
base as it is attached to the mounting surface. Flatness of the
mounting surface shall be held to tolerances specified by the
hoist manufacturer.
- The hoist shall be anchored so as to resist at least two times
any reaction induced at the maximum attainable line pull and shall
be anchored so that the hoist will not twist or turn.
- If the hoist is mounted to a truck chassis, it shall be
properly aligned and anchored in at least two corners to prevent
movement, and the wheels shall be properly chocked.
11. Drums.
- The hoist drum shall be capable of raising or lowering 125% of
the rated load of the hoist.
- The hoist drum shall have a positive means of attaching the
wire rope to the drum.
- There shall always be at least three full wraps of wire rope
on the hoist drum when personnel are being hoisted.
- During operation, the flange shall be two times the wire rope
diameter higher than the top layer of wire rope at all times.
12. Brakes and Clutches.
- Brakes and clutches shall be capable of arresting any
over-speed descent of the load.
- The hoist shall be provided with a primary brake and at least
one independent secondary brake, each capable of stopping and
holding 125% of the lifting capacity of the hoist.
- The primary brake shall be directly connected to the drive
train of the hoisting machine, and shall not be connected through
belts, chains, clutches or screw-type devices.
- The secondary brake shall be an automatic emergency-type brake
that, if actuated during each stopping cycle, shall not engage
before the hoist is stopped by the primary brake.
- When a secondary brake is actuated, it shall stop and hold the
load within a vertical distance of 24 inches.
- Brakes and clutches shall be adjusted, where necessary, to
compensate for wear and to maintain adequate force on springs
where used.
- Powered lowering must be used.
- When power brakes having no continuous mechanical linkage
between the actuating and braking mechanism are used for
controlling loads, an automatic means shall be provided to set the
brake to prevent the load from falling in the event of loss of
brake actuating power.
- Static brakes shall be provided to prevent the drum from
rotating in the lowering direction and shall be capable of holding
the rated load indefinitely without attention from the operator.
- Brakes shall be automatically applied upon return of the
control lever to its center (neutral) position.
- Brakes applied on stopped hoist drums shall have sufficient
impact capacity to hold 1.5 times the rated torque of the hoist.
13. Hoist Controls.
- Power plant controls shall be within easy reach of the
operator and shall include a means to start and stop, control
speed of internal combustion engines, stop prime mover under
emergency conditions, and shift selective transmissions.
- All controls used during the normal operation of the hoist
shall be located within easy reach of the operator at the
operator's station.
- Controls shall be clearly marked (or be part of a control
arrangement diagram) and easily visible from the operator's
station.
- Foot-operated pedals, where provided, shall be constructed and
maintained so the operator's feet will not readily slip off and
the force necessary to move the pedals can be easily applied.
- The controls shall be self-centering controls (i.e., "deadman"
type) that will return the machine to neutral and engage the drum
brakes if the control lever is released.
14. Wire Rope and Rigging
- All wire rope and rigging shall be inspected daily before use.
- All eyes in wire rope slings shall be fabricated with
thimbles.
- All eyes in wire rope slings shall:
(1) Be made with swaged-type fittings; and,
(2) Be field fabricated by a qualified person or factory
made.
15. Hoist Operator.
- The hoist operator shall have classroom training, a minimum of
40 hours experience as a hoist operator, not less than 8 hours
experience in the operation of the specified hoist or one of the
same type, and demonstrated the ability to safely operate the
hoist.
- The employer shall not allow an employee to operate a hoist
when that employee is physically or mentally unfit.
- The hoist operator shall be responsible for those operations
under his/her direct control. Whenever there is any doubt as to
safety, the operator shall have the authority to stop and refuse
to handle the load until safety has been assured.
- The hoist operator shall remain at the controls at all times
when personnel are on the hoist line.
- Before starting the hoist, the operator shall ensure that:
(1) The daily inspection has been conducted;
(2) All controls are in the "off" position; and,
(3) All personnel are in the clear.
16. Hoist Inspections.
- Routine inspections.
(1) Each day before use all hoists shall be
visually inspected by a qualified person.
(2) All hoists
shall be inspected thoroughly at three month intervals by a
qualified person, as will any hoists that have been idle for more
than one month but less than six months. Such inspection will
include a hands-on operation of all moving parts to ensure that
they are intact and will properly function before being put into
service.
- All hoists shall undergo a tear-down inspection annually
unless the following conditions exist that allow for less frequent
tear-down inspections.
(1) A hoist that has been idle for a period of
over six (6) months shall be given an annual inspection which
includes the hoist being completely disassembled, cleaned and
inspected. Parts such as pins, bearings, shafts, gears, brake
plates, etc. found worn, cracked, corroded, distorted or otherwise
non-functional must be replaced before the hoist is used.
(2) Hoists with infrequent to moderate usage (hoists that
have been used for fifty (50) hours or less per month and normally
operate at considerably less than the hoist rated capacity based
on the average use over a month) may go up to thirty-six (36)
months between tear down inspections if serviced under a
preventive maintenance program (as specified by the manufacturer)
that includes annual hydraulic oil sample analysis. An oil sample
analysis, meaning a laboratory analysis, is used to evaluate the
mechanical integrity of the hoist. Oil in these hoists shall be
changed at least on an annual basis, just after the oil analysis
is performed. Hoists not subjected to recommended oil sample
analysis shall undergo an annual tear-down inspection.
(3)
Hoists that experience heavy usage (hoists that are used for more
than fifty (50) hours per month) may go up to twenty-four (24)
months between tear-down inspections if serviced under a
preventive maintenance program as in (2) above.
(4) Any
rebuilt hoist assembly must be line pull tested to the rated load.
The hoist drum must be rotated several times in both raising and
lowering directions under full-rated load, while checking for
smooth operation.
INDEX
Access
Accident
Citation
Compliance
Construction
Emergency
Employee
Employer
Enforcement
Federal Program Change
General Duty Clause
Inspection
Personnel
Regional Administrator
State
Training |