AFI91-203_Chapter_16.pdf

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Chapter 16

MOBILE ELEVATING WORK PLATFORMS

16.1. General Information. This chapter applies to vehicle-mounted elevating and rotating platforms, including work platforms, fire fighting aerial devices and aircraft maintenance equipment used for elevating workers. It also applies to all manually-propelled and self-propelled mobile work platforms (including ladder stands) and rolling (mobile) scaffolds (towers). In some cases, the Air Force changes the design of commercially purchased mobile work platforms and scaffolds or builds this equipment; therefore, this chapter includes essential information on loads, rules and requirements for design, construction and use of mobile work platforms and scaffolds.

Also refer to 29 CFR 1910.28., Safety Requirements for Scaffolding.

16.2. Hazards.

16.2.1. Refer to Chapter 1, Introduction, paragraph 1.5., and AFI 91-202, The US Air Force Mishap Prevention Program, for further information on the JSA and job safety lesson plan.

Note: A JSA is not required when existing guidance adequately covers all safety requirements of an operation or process. Examples are TO 00-25-172, Ground Servicing of Aircraft and Static Grounding/Bonding. Refer to AFI 91-202, Attachment 5, Job Safety Training Outline (JSTO), for additional guidance and information.

16.2.2. Refer to Chapter 2, Human Factors, Chapter 3, Physical Hazards, and Chapter 14, Personal Protective Equipment (PPE), for additional guidance.

16.2.3. Deleted.

16.3. General Requirements. The potential for worker injury, death and property damage is reduced by proper platform and scaffold (tower) design, thorough operator training and inspections, good equipment maintenance and supervisor enforcement of safe work practices.

Supervisors shall ensure workers are physically capable of work at high elevations. Workers, too, must be alert to signs or symptoms from co-workers such as decreased performance, change in attitude and/or physical changes, etc., which could lead to a mishap.

16.4. Vehicle-Mounted Elevating and Rotating Work Platforms.

16.4.1. Procurement. Commercial aerial devices procured for Air Force fire fighting purposes shall conform to NFPA 1901, Standard for Automotive Fire Apparatus. All other aerial devices, either commercially procured or constructed by the Air Force for mission specific needs, shall conform to ANSI A92.2., Vehicle Mounted Elevating and Rotating Aerial Devices.

16.4.2. Modifications. Modifications shall conform to ANSI A92.2. and 29 CFR 1910.67., Vehicle-Mounted Elevating and Rotating Work Platforms, and shall be documented on the appropriate form. Authorized modifications include temporary removal of installed equipment not needed for a particular mission or modification to provide a new or improved capability.

Warning: Any modification which removes or defeats any safety device or feature on an aerial device is prohibited.

16.4.3. Clearances.

16.4.3.1. Electrical. Maintain the following clearances when operating aerial lifts under, over, by or near electric power lines.

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16.4.3.1.1. For lines rated 50 kilovolts (kV) or less, the minimum clearance between lines and any part of the aerial lift shall be at least 10 feet (305 centimeter [cm]).

16.4.3.1.2. For lines rated over 50 kilovolts (kV), the minimum clearance between lines and any part of the aerial lift shall be at least 10 feet (305 cm) plus 4 inches (10

cm) for each 10 kV over 50 kV. (T-0) Refer to 29 CFR 1910.269 for additional information.

16.4.3.2. Exceptions: Requirements in paragraph 16.4.3. do not apply if:

16.4.3.2.1. The aerial device is insulated for the work and work is performed by trained communications outside plant workers, line clearance tree-trimming workers or exterior electric linemen.

16.4.3.2.2. Electric power transmission or distribution lines have been de-energized and visibly grounded at point of work or where insulating barriers (not part of or attached to the aerial lift) have been erected to prevent physical contact with the lines.

16.4.3.2.3. Insulating barriers (rated for the voltage of lines being guarded and not part of or attached to the vehicle or its raised structure) are installed to prevent contact with lines. In this instance, the clearance may be reduced to a distance within the designed working dimensions of the insulating barrier. Refer to UFC 3-560-01, Electrical Safety, O & M, for additional information.

16.4.3.2.4. Aerial lift is insulated for voltage involved and work is performed by a qualified person. In this instance, the clearance between non-insulated parts of the aerial lift and power line may be reduced to the distance in UFC 3-560-01, Electrical Safety, O & M, Table 10-9.

16.4.3.2.5. An aerial lift or equipment contacts an electrical conductor. In this instance, the vehicle, equipment and attachments shall be considered energized. Personnel standing on the ground shall not contact any part of the lift unless using protective equipment rated for the voltage. Refer to Chapter 30, Communications Cable, Antenna and Communications Systems, for additional information.

16.4.3.3. Aircraft. When operating aerial lifts under, over, by or near aircraft, ensure adequate clearance is maintained to allow for slight movement of both the aircraft and aerial equipment caused by light winds. See paragraph 16.4.6.9.

16.4.4. Proximity Warning Devices. Proximity warning devices may be installed on aerial platforms but will not release the operator from assuring safe clearance IAW paragraph 16.4.3.

16.4.5. Inspection and Test Procedures.

16.4.5.1. Aerial ladders shall be inspected and tested annually or immediately following any activity when it is known, or suspected, to have been loaded beyond its maximum load capacity, or immediately following any repair of any ladder assembly structural or mechanical component. Refer to NFPA 1914, Standard for Testing Fire Department Aerial Devices, for inspection requirements. Inspections are the joint responsibility of the principal operator and vehicle mechanic qualified to perform annual inspections.

Document inspections and tests IAW AFI 23-302, Vehicle Management. Note: Aerial devices used for firefighting shall be inspected and tested at least annually IAW NFPA 1914. Qualified Fire Emergency Services (FES) Flight personnel may perform many of the

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tests and inspection actions; however, it is recommended they be performed by a third-party testing company or the aerial device manufacturer. A record of the inspection and tests shall be documented IAW AFI 23-302.

16.4.5.2. Articulating and extendible boom platforms shall be inspected and tested annually. (T-0) Special inspections and tests shall be conducted immediately following any use where the work platform may have been loaded beyond the manufacturer‘s rated capacity, or immediately following any repair of a boom or work platform assembly structural or mechanical component. (T-0) Refer to the manufacturer’s manual for inspection requirements. Inspections shall be a joint effort by the principal operator and a vehicle mechanic qualified to perform annual inspections of the vehicle. (T-1) The inspection and test shall be documented IAW AFI 24-302. (T-1) When the personnel platform is attached to a telescoping derrick or crane with a rated capacity higher than that of the work platform, test procedures contained herein shall not apply and testing shall be accomplished IAW applicable technical orders (TOs) or manufacturer‘s maintenance manual. (T-1)

16.4.5.3. Refer to 29 CFR 1926.1400., Cranes and Derricks in Construction, for information on use of cranes or derricks to hoist personnel work platforms.

16.4.6. Operations.

16.4.6.1. ANSI A92.2. requires aerial device manufacturers provide manuals to dealers and direct sale purchasers. Air Force users shall ensure manuals are readily available (stored in weather resistant compartment provided by manufacturer) to workers. These manuals shall contain:

16.4.6.1.1. Description, specifications and ratings of the aerial device.

16.4.6.1.2. Operating instructions for aerial device and its auxiliary systems.

16.4.6.1.3. Precautions relating to multiple configurations such as performing aerial work from a moving vehicle.

16.4.6.1.4. Instructions regarding routine maintenance and frequency of recommended maintenance.

16.4.6.1.5. Replacement part information.

16.4.6.1.6. Instruction markings per paragraph 16.4.6.2.

16.4.6.2. Each aerial device shall have a clearly visible plate or plates (located in a readily accessible area) stating:

16.4.6.2.1. Make, model and manufacturer’s serial number.

16.4.6.2.2. Rated capacity.

16.4.6.2.3. Platform height.

16.4.6.2.4. Maximum recommended operating pressures of hydraulic and/or pneumatic systems.

16.4.6.2.5. Hazards inherent in operation of an aerial device.

16.4.6.2.6. Manufacturer’s marking which describes the function of each control.

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16.4.6.2.7. Insulated or non-insulated. Note: Insulating aerial devices do not protect personnel from phase to phase or phase to ground contacts at the platform end.

16.4.6.2.8. Qualification voltage and date of test, if applicable.

16.4.6.2.9. Year of manufacture.

16.4.6.2.10. Number of platforms.

16.4.6.2.11. Category of aerial device.

16.4.6.2.12. Manufacturer’s rated line voltage. Where alternative configurations are possible, the plate will show by chart, schematic or scale the capacities of all combinations in their operating positions and cautions or restrictions, or both, for operation of all alternate or combinations of alternate configurations. These plates shall not be removed from the device, painted over or otherwise made unavailable for reference by the operator. Note: If an aerial device does not have a plate attached, contact the manufacturer and do not use the aerial lift until the plate is received. This plate shall not be removed or painted over.

16.4.6.3. Workers required to use vehicle-mounted elevating and rotating work platforms shall be thoroughly trained in all aspects of the job before using this equipment. This shall include “hands-on-training” prior to actual “on-the-job” training tasks. Completion of operator training and specific qualification shall be documented in individual’s training records (MIMICs, MIS or other data retrieval system). Reference Attachment 2, Minimum Mandatory Requirements for Aerial Lift Training and Training Plans. Note: While these requirements relate to aerial lifts, a similar level of detail is required when developing training plans and training personnel on other powered or potentially hazardous equipment.

16.4.6.4. Before a mobile unit is moved for travel, the aerial device shall be secured in the specified lower traveling position (to prevent rotation) by the use of cradles or locking devices IAW manufacturer’s instructions.

16.4.6.5. The unit shall be visually inspected and lift controls tested prior to each shift or day’s work to determine the unit and controls are in safe working condition. The override feature explained in paragraph 16.4.6.6. shall be tested at this time. IAW ANSI A92.2., a record of this test shall only be documented if a discrepancy was found with the unit during the inspection.

16.4.6.6. Articulating and extendible boom platforms, primarily designed as personnel carriers, shall have both platform (upper) and lower controls. (T-0) Upper controls shall be in or beside the platform within easy reach of the operator. (T-0) In order to prevent inadvertent actuation of the platform boom positioning controls, operation of an unlocking device shall precede use of the control itself and shall be maintained simultaneously during use of the controls. (T-0) The unlocking device may be incorporated into each control.

Lower controls shall override upper controls. (T-0) Controls shall be plainly marked with their function. (T-0) The override mode shall prevent boom movement with the lower control station unattended. Lower level controls shall not be operated without permission from the employee in the lift, except in an emergency. Whenever a worker is in or on an elevated work platform, at least one person qualified to operate the equipment shall be stationed near the lower level control panel. (T-0) Exception: Personnel working in or on

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an elevated boom without a qualified person near the lower level control panel is permitted if manufacturer’s instructions allows for such operations.

16.4.6.6.1. Emergency Stop. The platform shall have an emergency stop control which will stop all platform movement. This control shall not require continuous operator actuation to stop movement.

16.4.6.6.2. Outrigger Controls. Aerial device outrigger controls shall be guarded to protect against inadvertent operation, and shall return to neutral when released by the operator. These controls shall be located so the operator can see the outrigger being operated.

16.4.6.7. Boom and basket load limits specified by the manufacturer shall not be exceeded.

16.4.6.8. Aerial lift trucks shall not be moved with the boom elevated and personnel in the basket unless the lift truck is specifically designed for such operation. In all cases, the manufacturer’s operating instructions shall be followed.

16.4.6.9. Vehicle-mounted elevating and rotating work platforms shall not be used during high winds, thunderstorms or any other adverse or mission-limiting weather conditions which could endanger workers using the platform. Refer to the operator’s manual or applicable TO for specified wind limits.

16.4.6.10. Platforms other than buckets or baskets shall include a guardrail system which shall:

16.4.6.10.1. Include a top rail, 42 inches high, and at least one rail midway between top rail and platform surface around its upper periphery. Both rails shall withstand 300 pounds of force applied in any direction. (T-0)

16.4.6.10.2. Include toeboards on all sides of platforms. Toeboards shall be securely fastened in place and with not more than 1/4-inch clearance above floor level. (T-0) Exception: A toeboard is not required at the access opening. Where there is exposure to personnel or electrical wires below the platform, removable toeboards or the equivalent shall be provided IAW 29 CFR 1910.23. (T-0) The minimum toeboard height shall be four (4) inches. (T-0)

16.4.6.10.3. Include access for personnel entering the platform in the lowered position.

Access steps or rungs shall have a slip-resistant surface.

16.4.6.11. A full body harness and lanyard (sized to limit free fall distance to six (6) feet or less, or the free fall distance permitted by the system, whichever is less) shall be worn by each bucket or platform occupant. Each lanyard shall be attached to a designated anchor point on the boom or basket. Refer to 29 CFR 1910.66., Personal Fall Arrest System, Appendix C (d)(1)(iv).

16.4.6.12. Belting off to an adjacent pole, structure or equipment while working from an aerial lift shall not be permitted.

16.4.6.13. Workers shall stand firmly on the basket floor, not sit or climb on edge of basket or use planks, ladders or other devices for a work position.

16.4.6.14. Climber’s equipment shall not be worn while performing work from an aerial lift.

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16.4.6.15. Aerial devices, including insulated aerial devices, shall not be brought into contact with energized or potentially energized conductors. Workers shall not rely on dielectric capabilities of aerial devices.

16.4.6.16. Consult BE prior to work near suspected sources of non-ionizing radiation, i.e., radar and microwave equipment. Refer to Chapter 30 for additional guidance.

16.4.6.17. Before using an aerial device, the worksite shall be surveyed for hazards, such as un-tamped earth fills, ditches, drop-offs and floor obstructions, debris, overhead obstructions and electrical conductors, weather conditions and presence of unauthorized persons.

16.4.6.18. Before and during each use, the operator shall:

16.4.6.18.1. Check for overhead obstructions and electrical conductors.

16.4.6.18.2. Ensure load weight does not exceed manufacturer’s rated capacity.

16.4.6.18.3. Ensure outriggers and stabilizers are used if required by manufacturer's instructions.

16.4.6.18.4. Ensure guardrails are properly installed, including bolts, pins or other locking devices on removable railings and attachments, and that gates are closed.

16.4.6.18.5. Use outrigger pads when necessary to provide firm footing.

16.4.6.18.6. Set brakes.

16.4.6.18.7. Chock wheels before using the lift on an incline.

16.4.7. Maintenance and Repair of Powered and/or Mobile Units:

16.4.7.1. If deficiencies affecting safe operation are discovered during the daily operator inspection (or during use), the equipment shall immediately be removed from service until repaired. The manufacturer’s recommended maintenance procedures shall be followed and tests outlined in paragraph 16.4.5. shall be conducted prior to returning an aerial device to service following repairs to the ladder, boom or work platform.

16.4.7.2. All repairs shall be accomplished by qualified personnel.

16.5. Manually-Propelled and Self-Propelled Mobile Work Platform and Scaffolds (Towers).

16.5.1. Work platforms with work levels four (4) feet or higher and accessed by a ladder or stairway at an angle over 60 degrees, shall have guardrails, midrails and toeboards IAW paragraph 16.4.6.10 on all four (4) sides of the work platform. (T-1) Exception: A toe board is not required at the access opening.

16.5.2. Working Loads:

16.5.2.1. Work platforms and scaffolds shall carry their designed load under all conditions of use. Aircraft maintenance work platforms shall support design loads listed in their TOs.

Parts, additions or accessories for safe use of platforms and scaffolds shall be part of the design.

16.5.2.2. Specific design and construction requirements are not part of this standard due to the wide variety of materials and design possibilities. However, the design used shall

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produce a mobile ladder stand or scaffold that will safely hold specified loads. Materials selected shall be strong enough to meet test requirements and protected against corrosion and deterioration.

16.5.2.2.1. The design working load of ladder stands shall be calculated based on one or more 250-pound persons with 50 pounds of equipment each.

16.5.2.2.2. Scaffold design work loads shall be calculated based on:

16.5.2.2.2.1. Light - Designed and constructed for a work load of 25 pounds per square foot.

16.5.2.2.2.2. Medium - Designed and constructed for a work load of 50 pounds per square foot.

16.5.2.2.2.3. Heavy - Designed and constructed for a work load of 75 pounds per square foot.

Note: Ladder stands and scaffolds shall support at least four (4) times the design work load.

16.5.2.3. Mobile ladder stand and scaffold materials shall meet strength, dimension and weight specifications in this standard to safely support the design work load.

16.5.2.4. Bolts or other fasteners used to assemble ladders, scaffolds and towers shall be large enough and in sufficient quantity at each connection to develop designed strength.

16.5.2.5. The operator shall ensure there are no sharp edges, burrs or other hazards to personnel on exposed surfaces.

16.5.3. Work Levels.

16.5.3.1. Maximum work level height shall not exceed four (4) times the minimum or least base dimension (width) of any mobile ladder stand or scaffold. Where the basic mobile unit does not meet this requirement, suitable outrigger frames shall be used to obtain this least base dimension or the unit shall be tied with guy wires or braced to keep the unit from tipping.

16.5.3.2. The minimum platform work level width for mobile scaffolds (towers) shall not be less than 20 inches. Ladder stands shall have a minimum step width of 16 inches.

16.5.3.3. The supporting structure for the work level shall be rigidly braced, using cross bracing or diagonal bracing with rigid platforms at each work level.

16.5.3.4. Ladder stand steps shall have slip-resistant treads or a slip-resistant coating.

16.5.3.5. The work level platform of scaffolds shall be wood, aluminum, plywood planking, steel or expanded metal, for the scaffold’s full width, except for necessary openings. Work platforms shall be secured to the support structure. Planking shall be 2-inch (nominal) scaffold grade minimum 1,500 fiber (f) (stress grade) lumber or equivalent.

16.5.3.6. Scaffold work platforms four (4) feet or higher shall have guardrails, midrails and toeboards IAW paragraph 16.4.6.10.

16.5.3.7. Scaffolds shall have a climbing ladder or stairway (for access and egress) affixed or built into the scaffold. The ladder or stairway shall be located so it will not tip the scaffold. A landing platform shall be provided at intervals not exceeding 30 feet.

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16.5.3.8. Self-propelled elevating work platforms and manually-propelled mobile work platforms shall not be moved with personnel on the working platform unless allowed by manufacturer’s instructions. Locking pins or other devices, as required, shall be in place IAW equipment-specific TOs or manufacturer’s specifications before anyone is allowed to ascend the stairs or ladder. (T-0) If allowed by manufacturer’s instruction the following requirements need to be accomplished prior to any movement with personnel on the working platform:

16.5.3.8.1. Guardrails, mid-rails, and toe-boards shall be installed on all exposed sides in accordance with paragraph 16.4.6.10. (T-0)

16.5.3.8.2. The floor or surface shall be within 3° (0.6288 inches of rise in 12 inches of run) of level, smooth (the equivalent of broom-finished concrete) and free from pits, holes or obstructions. (T-0)

16.5.3.8.3. The minimum dimension of the scaffolding base when ready for rolling shall be at least one-half of the height. (T-0) Outriggers, if used, shall be installed on all four sides of the scaffold and then can be included as part of the base dimension.

(T-0) Note: Measure at the widest width of the base.

16.5.3.8.4. All tools and materials are secured or removed from the platform before the mobile scaffold is moved.

16.5.3.8.5. Employees on the mobile scaffold shall be advised by a spotter and be aware of each movement in advance. (T-0)

16.5.3.8.6. Employees on the work platform of the mobile scaffold may move the scaffold when the mobile scaffold is equipped with a manual system in which the propelling force is applied to the wheels only and cannot exceed normal walking speed.

16.5.3.8.7. The force necessary to move the mobile scaffold shall be applied as close to the base as practicable, and provision shall be made to stabilize the tower during movement from one location to another. (T-0)

16.5.3.9. Full-body harnesses shall be worn with lanyard attached to the structural anchor point when using self-propelled mobile work platforms (if guard rails will be removed) with manufacturer-installed structural anchor points and the platform elevated four (4) feet or more above the surface. Self-propelled work platforms manufactured without an approved structural anchor point shall have protective guardrails, midrails (when required) and toeboards installed on all open sides IAW paragraph 16.5.1. When within 14 inches of the work surface, i.e., aircraft and buildings, guardrails need not be in place on the side that is within 14 inches of a working surface. Bolts, pins or other locking devices shall be provided and used on all removable railings and attachments.

16.5.3.10. Personal fall arrest equipment anchorages shall be capable of supporting at least 5,000 pounds (22.2 kilonewton [kN]) per worker attached, or shall be designed, installed, and used as part of a complete personal fall arrest system which maintains a safety factor of two, under the supervision of a qualified person. (See Chapter 13, Fall Protection, and OSHA Standard 29 CFR 1910.66., Personal Fall Arrest System, Appendix C.)

16.5.3.11. Lanyards, “D” rings, snap-hooks and all fall arrest system components shall sustain a minimum 5,000 pound tensile load IAW 29 CFR 1910.66., Appendix C.

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16.5.4. Operations.

16.5.4.1. Training requirements in paragraph 16.4.6.3 also apply to all manually-propelled elevating aerial platforms and self-propelled elevating work platforms.

16.5.4.2. Operators shall know the location of operating and safety manuals, including the manual defining dealer, owner, lessor, lessee, user and operator responsibilities on the aerial platform. Operators shall be familiar with and use these manuals when questions arise.

16.5.4.3. Aerial platforms shall be given a visual inspection and functional test before use each day or at the beginning of each shift including, but not limited to, the following:

16.5.4.3.1. Operating and emergency controls.

16.5.4.3.2. Safety devices.

16.5.4.3.3. Personal protective devices, including fall protection.

16.5.4.3.4. Air, hydraulic and fuel system leaks.

16.5.4.3.5. Cables and wiring harness.

16.5.4.3.6. Loose or missing parts.

16.5.4.3.7. Tires and wheels.

16.5.4.3.8. Placards, warnings and control markings.

16.5.4.3.9. Outriggers, stabilizers and other structures.

16.5.4.3.10. Guardrail system, including bolts, pins or other locking devices on all removable railings and attachments.

16.5.4.3.11. Any special items required by the manufacturer.

16.5.4.3.12. Inspection deficiencies shall be documented IAW applicable TO or local procedure for stands not covered by a TO. A visible indicator, i.e., AF Form 981, Out of Order, or other means shall be affixed to stands removed from service until repaired and returned to service.

16.5.4.4. Refer to paragraph 16.4.6.17. for workplace inspection information.

16.5.4.5. The operator shall ensure the following before each elevation of the platform:

16.5.4.5.1. The aerial platform is operated on a surface within the manufacturer’s limits.

16.5.4.5.2. Outriggers, stabilizers, extendable axles or other stability enhancing means are used as required by the manufacturer.

16.5.4.5.3. Guardrails are installed and access gates or openings are closed per manufacturer’s instructions, including bolts, pins or other locking devices on all removable railings and attachments.

16.5.4.5.4. The load and its distribution on the platform and any platform extensions do not exceed the manufacturer’s rated capacity for the specific configuration.

16.5.4.5.5. There is adequate clearance from overhead obstructions.

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16.5.4.5.6. Minimum safe approach distances to energized power lines and parts are maintained.

16.5.4.5.7. The operator and all personnel on the platform wear fall protection devices and other safety gear, as required, at all times.

16.5.4.6. Users shall inspect and maintain aerial platforms to ensure proper operation. The frequency of inspection and maintenance shall be based on the manufacturer’s recommendations and compatible with operating conditions and severity of the operating environment. Aerial platforms not in safe operating condition shall be immediately removed from service until repaired. A qualified person shall make repairs IAW manufacturer’s recommendations. This periodic inspection shall include those requirements in paragraphs 16.5.4.3. and 16.5.4.5.

16.5.4.7. Controls for manually elevated platforms shall be clearly marked for direction and function. Controls for platform elevating and lowering mechanisms shall be self-holding and readily accessible from the ground. Controls at the platform are optional.

16.5.4.8. Upper controls of power elevated platforms shall be:

16.5.4.8.1. Clearly marked as to direction and function;

16.5.4.8.2. A type that automatically returns to the off or neutral position when released;

16.5.4.8.3. Protected against inadvertent operation;

16.5.4.8.4. Readily accessible to the operator;

16.5.4.8.5. Designed to include a control that must be continuously activated for upper controls to function and that automatically returns to the off position when released.

16.5.4.9. Aerial platforms with a powered elevating assembly shall have a clearly marked emergency lowering means readily accessible from ground level.

16.5.4.10. The aerial platform shall have a readily identifiable emergency stop device at upper control and lower control stations that will stop powered functions and platform movement.

16.5.4.11. The control system shall be designed so a single control system malfunction will not cause unintended platform movement.

16.5.5. Wheels And Casters:

16.5.5.1. Wheel and casters shall be sized to support four times the design working load.

16.5.5.2. Scaffold casters shall have a positive wheel and (or) swivel lock to prevent movement. Two of the four casters on ladder stands shall swivel and be lockable.

16.5.5.3. Screwjacks or other means for adjusting height shall be provided where leveling of the elevated work platform is required.

16.5.5.4. At least two brakes, wheel locks or permanently installed jacks shall be operable on all mobile work platforms.

16.5.6. Mobile Tubular Welded Frame Scaffolds:

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16.5.6.1. Scaffolds shall be designed to comply with paragraphs 16.4.1, 16.4.2. and 16.4.4.

16.5.6.2. Scaffold vertical members shall be properly braced by cross or diagonal braces.

Braces shall automatically square and align vertical members so the erected scaffold is always plumb, square and rigid.

16.5.6.3. Spacing of panels or frames shall be consistent with loads imposed. Frames shall be placed one on top the other with coupling or stacking pins to provide vertical alignment of legs.

16.5.6.4. Panels shall be locked together vertically by pins or equivalent if uplift can occur.

16.5.6.5. Scaffold over 50 feet in height shall be erected IAW manufacturer’s instructions and under the supervision of a qualified professional engineer. The installation civil engineering activity is the authorizing agency for scaffold erection.

16.5.7. Mobile Tubular Welded Sectional Folding Scaffolds:

16.5.7.1. General. Scaffolds, including sectional stairway and sectional ladder scaffolds, shall be designed and erected IAW paragraphs 16.4.1., 16.4.2., 16.4.4. and 16.5.6.5.

16.5.7.2. Stairway. Each section of folding stairway scaffold shall include a stairway, detachable work platform and a set of pivoting and hinged folding diagonal and horizontal braces.

16.5.7.3. Sectional Folding Stairway Scaffolds. These are medium duty scaffolds (light duty when equipped with a “high clearance” base section). Note: High clearance bases have a greater open space so the scaffold may be placed over obstructions like machinery or shrubbery. When high clearance bases are used to support sectional folding stairway scaffolds, the entire scaffold’s load capacity shall be reduced. Sectional folding stairway scaffolds shall not exceed 4 ½ feet in width and 6 feet in length.

16.5.7.4. Sectional Folding Ladder Scaffolds. Sectional folding ladder scaffolds are light duty scaffolds (includes special base [open end] sections designed for high clearance over obstructions). For special applications, 6-foot folding ladder scaffolds, except high clearance base sections, shall be designed as medium duty scaffolds. A sectional folding ladder scaffold shall not exceed 6 feet 6 inches in width for a 6-foot long unit, 8 feet 6 inches for an 8-foot unit, or 10 feet 6 inches for a 10-foot long unit. End frames of sectional ladder and stairway scaffolds shall be designed so horizontal bearers provide support for multiple planking levels.

16.5.8. Mobile Tube and Coupler Scaffolds:

16.5.8.1. Design. Units shall be designed IAW paragraphs 16.4.1., 16.4.2. and 16.4.4.

16.5.8.2. Material. Couplers shall be made of structural type material, such as drop-forged steel, malleable iron or structural grade aluminum. Use of gray cast iron is prohibited.

16.5.8.3. Erection of Scaffold. Refer to paragraph 16.5.6.5.

16.5.9. Mobile Work Platforms:

16.5.9.1. Design. Units shall be designed IAW paragraphs 16.4.1., 16.4.2. and 16.4.4.

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16.5.9.2. Base Width. The minimum base width shall conform to paragraph 16.5.3.2.

16.5.9.3. Bracing. Rigid diagonal bracing to vertical members shall be provided.

16.5.10. Mobile Ladder Stands:

16.5.10.1. Design. Units shall comply with applicable requirements of paragraphs 16.4.1.,

16.4.2. and 16.4.4.

16.5.10.2. Base Width. Minimum base width shall be IAW paragraph 16.5.3.2. Maximum base section length shall be the total length of combined steps and top assembly, measured horizontally, plus 5/8 inch per step of rise.

16.5.10.3. Steps. Steps shall be uniformly spaced, with a rise of 9 inches to 10 inches, and a depth of at least 7 inches. Slope of the steps section shall be 55 to 60 degrees, measured from the horizontal.

16.5.10.4. Handrails. Units with more than 4 steps or 60 inches vertical height to the top step shall be equipped with handrails. Handrails shall be at least 29 inches high and the same height all along the step, measured vertically from the center of the step.

16.5.10.5. Load design shall meet requirements of paragraph 16.5.2.2.1.

16.5.11. Mobile Work Platforms and Ladder Stands shall:

16.5.11.1. Meet criteria in paragraphs 16.5.9. and 16.5.10. If these mobile work platforms have steps, they shall meet mobile ladder stand criteria for step dimensions and handrails.

16.5.11.2. Be maintained free of grease, oil, ice, snow, mud or any other slippery substance or object which could cause slips and falls. Step treads and walking surfaces shall be in good repair. Repair worn surfaces with suitable materials or make safe using abrasive or non-slip materials.

16.5.11.3. Removable guardrails may be used on all open sides of aircraft maintenance platforms. Guardrails removed for material handling shall be replaced as soon as material handling is complete. Protective guardrails are not required at the platform entrance if there is a ramp or stairway (angle less than 60 degrees) IAW paragraph 16.5.1. Protective guardrails shall only be removed from the side(s) of the platform positioned as close as practical (less than 14 inches) and parallel to aircraft, building or other working surface.

Guardrails shall be installed on all open sides if platform levels are four (4) feet or higher above ground or floor. Bolts, pins or other locking devices shall be provided and used on all removable railings and attachments. Only guardrails and toeboards meeting criteria in paragraph 16.4.6.10. shall be used.

16.5.11.4. Prior to any user ascending a raised mobile platform: all locking devices (i.e., pins, collars, etc.) shall be installed, hydraulic pressure shall be released, the platform shall be slowly lowered until locking devices are securely engaged and hydraulic pressure valve(s) shall be closed. If the raisable portion of the platform cannot be elevated from ground level, the user may ascend to that platform portion and adjust platform height.

However, requirements for locking devices, pressure release and closing valves shall be met prior to starting any task or work.

16.5.11.4.1. Ascending/descending work platform. The climbing apparatus shall be considered a ladder if it does not meet step dimension criteria in paragraph 16.5.10.3.

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and/or the angle of the apparatus is greater than 60 degrees from horizontal. Personnel ascending/descending ladders shall face the ladder and maintain a firm hold on the ladder. Personnel ascending/descending stairs (less than or equal to 60 degrees) shall face the direction of travel and use hand rails as depicted in Figure 16.1.

16.5.11.4.2. Refer to Chapter 7, Walking Surfaces, Guarding Floor and Wall Openings, Fixed Stairs, and Portable and Fixed Ladders, for additional guidance on ladder safety.

16.5.11.5. Mark mobile work platforms with reflective materials to the maximum extent authorized by appropriate TOs, such as 35-1-3, Corrosion Prevention and Control, Cleaning, Painting, and Marking of USAF Support Equipment (SE). When not being transported, mobile work platforms shall be secured to prevent collision with aircraft, vehicles or other equipment. (T-1) Designated flightline storage areas for mobile work platforms shall be determined by AGE Flight Commander and Airfield Manager and approved by the Maintenance Group Commander. (T-1) Refer to Chapter 24, Aircraft Flight Line -Ground Operations and Activities, for further guidance.

16.5.11.6. Mobile work platforms shall be operationally inspected per the equipment TO or manufacturer’s owner manual and TO 00-20-1. (T-0) Maintenance work stands shall have four (in any combination) of the following: operational brakes, wheel locks or permanently installed jacks (e.g., two operational brakes and two permanently installed jacks). (T-1) No stand will be used unless all brakes are set and all wheel casters locked.

(T-1) Wheel will be locked either 90 or 180 degrees from the caster lock pin if it interferes with the wheel brake handle. (T-1) Wheel chocks may be used in conjunction with these requirements. Vehicle chocks may be constructed or locally manufactured IAW TO 00-25- 172, Ground Servicing of Aircraft and Static Grounding/Bonding, Section 4.1.2. Platforms shall be locked when not in use to avoid rolling down slanted surfaces or being moved by wind. (T-1) Stands with defects shall be tagged as unserviceable. (T-0)

Note 1: Some maintenance work stands may only have two operational brakes and no permanently installed jacks. Both brakes are required to be set.

Note 2: A daily inspection is not required for days the stand is not used.

16.5.11.7. When mobile work platforms are being moved:

16.5.11.7.1. Personnel and equipment may remain on self-propelled and manually-propelled work platforms when moved if manufacturer’s instructions allow such activity and the requirements of paragraph 16.5.3.8 and subparagraphs are followed.

16.5.11.7.2. Platforms to be towed shall be equipped with hitches designed for such purpose.

16.5.11.7.3. The following rules apply when platforms are towed by vehicles:

16.5.11.7.3.1. Maximum towing speed for one maintenance stand is 10 miles per hour and 5 miles per hour for two or more maintenance stands. However, when surfaces and terrain make it necessary, speed shall be reduced accordingly.

16.5.11.7.3.2. No more than four type B1, B4, B5 and similar small stands may be towed as follows: two sets of two in tandem on a double hitch or two in tandem on a single hitch. Type B3, J7 and similar large stands shall be towed singly on a center

AFI91-203 15 JUNE 2012 183

mounted hitch. Four-wheeled units shall not be towed behind two-wheeled units.

Large pieces of AGE, when towed in tandem, shall not block the driver’s vision of last item being towed.

16.5.11.7.3.3. Safety pins shall be used to secure pintle hooks and trailer hitches.

16.5.11.8. Mobile work platforms used where static electricity is hazardous to the work operation, such as fuel cell repair or refueling vehicle maintenance, shall be grounded and equipped with static discharge plates for personnel to dissipate accumulated static electricity.

16.5.11.9. Maintain mobile work platforms and ladder stands IAW appropriate 35-series TOs.

Figure 16.1. Ascending/Descending Work Platform.

Note: Angle less than or equal to 60º, personnel ascending/descending stairs shall face the direction of travel and use hand rails. If angle is greater than 60º the climbing device shall be considered a ladder and accessed like a ladder.

16.6. Mobile Elevating Work Platforms Checklist. This is not an all-inclusive checklist. It, like all checklists in this instruction, highlights some critical items contained within this chapter. Other requirements exist that are not included in the checklist. Where appropriate, MAJCOMs, FOAs, DRUs, local safety staffs and supervisors shall add to this checklist to include Command or individual location or shop-unique requirements and/or situations. (T-1)

16.6.1. Do operators of aerial lifts near electric power lines maintain proper clearances?

Reference 16.4.3

16.6.2. Are aerial ladders inspected and tested annually? Reference 16.4.5.1.

16.6.3. Are aerial ladders inspected immediately following any repair of a structural or mechanical component of the ladder assembly? Reference 16.4.5.1.

16.6.4. Is NFPA 1914, Standard for Testing Fire Department Aerial Devices, used as a guide by the principal operator and a qualified vehicle mechanic while performing tests or annual inspections of aerial ladders? Reference 16.4.5.1.

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16.6.5. Are articulating and extendible boom platforms inspected and tested annually?

Reference 16.4.5.2.

16.6.6. Is the manufacturer’s manual used as a guide by the principal vehicle operator and a qualified vehicle mechanic while performing tests or annual inspections of articulated and extendible boom platforms? Reference 16.4.5.2

16.6.7. Are tests and inspections of platforms recorded IAW AFI 23-302? Reference 16.4.5.2.

16.6.8. Is the aerial device manufacturer’s operator manual available for operator use?

Reference 16.4.6.1.

16.6.9. Have operators of vehicle-mounted elevating and rotating work platforms been thoroughly trained and qualified in the use of the equipment? Reference 16.4.6.3.

16.6.10. Are work platforms equipped with guardrails, midrails and toeboards on all four (4) sides of the platform, including the access opening to the platform? Reference 16.5.1.

16.6.11. Is the maximum height of mobile ladder stands or scaffolds restricted to a level no greater than four times the least base dimension of the supporting frame? Reference 16.5.3.1.

16.6.12. Are supporting structures for work levels rigidly braced? Reference 16.5.3.3.

16.6.13. Are the steps of all ladder stands constructed of slip-resistant materials or covered with a slip-resistant coating? Reference 16.5.3.4.

16.6.14. Is the work level platform of scaffolds secured to the support structure? Reference 16.5.3.5

16.6.15. Are guardrails, midrails and toeboards installed on all scaffolding with work levels four (4) feet or more above ground or floor level? Reference 16.5.3.6.

16.6.16. Do supervisors ensure personnel do not ride moving manually-propelled work platforms? Reference 16.5.3.8.

16.6.17. Are at least two (2) of four (4) casters on ladder stands or work platforms equipped with positive swivel locks or wheel locks to prevent movement? Reference 16.5.5.2.

16.6.18. Are screwjacks or other suitable means for adjusting height provided when leveling elevated work platform is required? Reference 16.5.5.3.

16.6.19. Are at least two (2) brakes, wheel locks or permanently installed jacks operational on all mobile work platforms? Reference 16.5.5.4.

16.6.20. Are structural type materials used for scaffold couplers (i.e., drop-forged steel, malleable iron, or structural grade aluminum)? Reference 16.5.8.2.

16.6.21. Are rigid diagonal bracings provided to the vertical members? Reference 16.5.9.3.

16.6.22. Are handrails provided on mobile ladder stands that have more than four steps or 60 inches vertical height? Reference 16.5.10.4.

16.6.23. Are protective guardrails and mid-rails (when required), installed and secured with bolts, pins or other locking devices on mobile work platforms and ladder stands for work four

(4) feet or more above ground or floor? Reference 16.5.11.3.

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16.6.24. Are reflective materials for marking mobile work platforms used to the maximum extent authorized by TOs? Reference 16.5.11.5.

16.6.25. Are work platforms secured against movement when not being transported?

Reference 16.5.11.5

16.6.26. Are mobile work platform and/or ladder stands inspected daily before use? Reference 16.5.11.6.

16.6.27. Are mobile platforms and ladders used for fuel cell repair or other hazardous areas equipped with bonding and (or) ground connections and static discharge plates for personnel to dissipate accumulated static electricity? Reference 16.5.11.8.

16.6.28. Is maintenance of mobile work platforms and ladder stands accomplished as required by applicable 35-series TOs? Reference 16.5.11.9.

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Chapter 17

SCAFFOLDING

17.1. General Information. This chapter applies to all scaffolding used in the Air Force, except rolling scaffolds (mobile towers), which are covered in Chapter 16, Mobile Elevating Work Platforms. It specifies criteria for assembly, erection, storage and safe use of scaffolding. Since the Air Force primarily uses pre-formed tubular scaffolding, construction requirements for wooden pole scaffolding are not part of this chapter. In the event an Air Force organization must construct a wood scaffold, the design and material specifications contained in 29 CFR 1910.28., Safety Requirements for Scaffolding, 29 CFR 1910 Subpart D, Walking-Working Surfaces, 29 CFR 1926 Subpart L, Scaffolds, and 29 CFR 1915.71., Scaffolds, Ladders and Other Working Surfaces, shall be followed. Refer to Chapter 16 for information on manually-propelled mobile ladder stands, mobile work platforms or mobile towers.

17.1.1. Procurement. Scaffolds and support equipment for Air Force use will meet design and construction specifications of 29 CFR 1910.28.

17.2. Hazards and Human Factors. Elevated work platforms and scaffolds present hazards associated with falls or falling objects. These hazards are usually the result of poorly designed equipment or from workers erecting them improperly or using them incorrectly. Further, workers can create hazards by building makeshift platforms, removing guardrails and toeboards, or failing to secure tools and equipment. These hazards can be minimized by properly designing platforms and scaffolds, by training personnel and by supervisors enforcing safe work practices. Supervisors must also consider the physiological effects of high places on individual workers, such as dizziness or instability. Factors such as illness, fatigue and physical deficiencies can also contribute to mishaps.

17.3. General Requirements.

17.3.1. Scaffolds shall be provided when work cannot be done safely from the ground or from solid construction and shall be constructed and erected only by qualified, trained personnel.

When ladders are used they will conform to requirements in Chapter 7, Walking Surfaces, Guarding Floor and Wall Openings, Fixed Industrial Stairs, and Portable and Fixed Ladders.

17.3.2. The footing or anchorage for scaffolds shall be designed to support the maximum intended load without settling or displacement. Unstable objects such as barrels, boxes, loose brick or concrete blocks shall not be used to support scaffolds or planks.

17.3.3. Guarding requirements.

17.3.3.1. Guardrails shall be installed on open sides and ends of platforms 4 feet or more (and toeboards, if 10 feet or more) above the ground or floor except:

17.3.3.1.1. Scaffolding wholly within the interior of a building and covering the entire floor area of any room providing no side is exposed to a hoistway, elevator shaft, stairwell or other floor openings.

17.3.3.1.2. Needle-beam scaffolds and floats used by structural iron workers.

17.3.3.2. Scaffold guarding will consist of: