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Assembly > Ergonomics



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Clamp Operator, Base Units Top
The operation consists of a two-person team working around a clamping system to build base cabinets. Stock material is loaded onto the clamp and secured into place by gluing and nailing. Both team members participate in all aspects of the operation. Each person has two different glue guns and a nail gun. A faceplate is first positioned into the clamp and glue is applied. The side panels are set in and clamped into place. Support blocks are glued and nailed in place. More glue is applied and the top and bottom are put into place. Exposed surfaces are glued and the back panel is set into place. The back is then nailed into place and the cabinet is lifted to the conveyer.

Potential Hazard:
  • Use of an extended wrist with finger force to activate the trigger mechanism during gluing can cause injury.
Possible Solutions:
  • Educate the operator on the importance of maintaining a neutral wrist while performing repetitive motions.

  • Redesign tools that make it easy for the operator to maintain a neutral wrist position.
Potential Hazard:
  • Ulnar deviation of the wrist with finger force to activate trigger mechanism of nail gun can cause injury.
Possible Solutions:
  • Provide a step to elevate the employee and make it easier to maintain a neutral wrist position.

  • Educate the operator on the importance of maintaining a neutral wrist while performing repetitive motions.

  • Realign the work surface to allow for a neutral wrist position while performing the task. Design a nail gun with a power grip to be used in these situations.
Potential Hazard:
  • Workers abduction of their arms to reach above shoulder height to get stock for construction of cabinet. Problem also exists when these bins are filled with feed stock. Potentially harmful loads are being elevated from waist height to head height. In addition, there are excessive finger and thumb pinch grip force movements, with ulnar deviation of the wrist while stocking the upper bins. Twisting of the body while lifting creates a torquing situation on the back vertebrae.
Possible Solutions:
  • Realign storage areas for feed stock so reaches above shoulder height or bending over to get material is not necessary.

  • Educate employees in proper lifting techniques.
Potential Hazard:
  • Using the hand as a mallet to pound and force components into position can cause injury.
Possible Solutions:
  • Provide mallets to use when force is needed to adjust portion of parts.

  • Train employees in the proper use of mallets where force is needed.
Potential Hazard:
  • Extended reaches and bending when gluing causes strain on the lower back and shoulder area.
Possible Solutions:
  • Realign the work surface for easier access without excessive reaches.

  • Have employees do only their half of cabinet to eliminate excessive reaches.

  • Evaluate the feasibility of raising the work surface for early stages of cabinet construction and lowering it for final stages.
Top


Base Department Top
The cabinets come down the conveyer, the surfaces are cleaned, and a template is used to drill guide holes for hinge screws. The door that already has the hinge on it is then attached to the cabinet.

Potential Hazard:
  • Extending the wrist while cleaning, drilling, and holding the template can cause injury.
Possible Solutions:
  • Educate the operator on the importance of maintaining a neutral wrist while performing repetitive motions.
Potential Hazard:
  • Bending over at the waist to work on cabinet hardware from the top can cause injury.
Possible Solutions:
  • Reposition the worker in front of the cabinet for tasks done within the cabinet.
Potential Hazard:
  • Bending over to pick up drawers for installation into cabinet can cause injury.
Possible Solutions:
  • Have drawers come in on conveyer at waist height to minimize bending.

  • Stack drawers on pallets that could be placed on a lifting table to prevent bending.
Potential Hazard:
  • Using a palm pinch grip to lift a door and abducting the elbow and holding the door above shoulder height to support right hand doors while hinges are screwed into place can cause injury.
Possible Solutions:
  • Use two-man teams to install the doors. Have one person hold the door in position while the other secures the hinge in place.

  • Design a clamp on the hinge so the door does not need to be held while the screws are secured.

  • Provide a side bar for screw guns so both hands can be used during operation.
Potential Hazard:
  • Deviating the wrist while securing the top and bottom hinges of larger cabinets can cause injury.
Possible Solutions:
  • Provide movable platforms to bring employees up to a level where they can perform the job in an ergonomically safe manner.

  • Educate the operator on the importance of maintaining a neutral wrist while performing repetitive motions.
Top


Sub Assembly - Wall Unit Top
Potential Hazard:
  • As crew gun creates excessive force on the wrist and shoulder during operation.
Possible Solutions:
  • Suspend the screw gun from an assist sling to reduce the force required to lift the gun.
Potential Hazard:
  • Excessive bending to place hardware into cabinets can cause injury.
Possible Solutions:
  • Remove boxes from under conveyer line to allow employee better access to work area.
Top


Clamping Operator - Specials, Large Wall Unit Top
The operation builds large wall units. These are built on a rack that holds the materials at about a 30-degree angle.

Potential Hazard:
  • Extending the reach with the arm above shoulder height and supporting the weight of the nailing gun can cause injury.
Possible Solutions:
  • Reposition equipment to allow easier access to all sides of the cabinet.
  • Provide stools or platforms to allow workers to elevate themselves and gain better access to work.
Potential Hazard:
  • Deviation of the wrist along with force which is required for activation of the nail gun.
Possible Solutions:
  • Educate the operator on the importance of maintaining a neutral wrist while performing repetitive motions.
  • Institute the procedures mentioned above.
Top
 

BLS Clamp Operator - Specials Top
The operators place a face plate into the clamp and apply glue to several of the surfaces. The top and bottom are set in place and nailed. The shelving area is secured in place with screws and a sheet of pliable material is wrapped around the back. This material is nailed into place using a nail gun.

Potential Hazard:

  • Extending the reach with a wrist deviation while operating the nailing gun can cause injury.
Possible Solutions:
  • Educate the operator on the importance of maintaining a neutral wrist while performing repetitive motions.
  • Reposition the work.
  • Have each member of the team do the nailing on his or her own side of the cabinet. 
Potential Hazard:
  • Deviating the wrist with an abducted elbow while operating the nailing gun and attaching cabinet backs can cause injury.
Possible Solutions:
  • Redesign the nail gun to incorporate a power grip.
  • Suspend the nail gun with a sling to remove stress from the operator.
  • Provide steps so employees can elevate themselves in relation with work surface.
Potential Hazard:
  • Extending the reach with a deviated wrist to get inside of cabinet to secure a lazy susan in place can cause injury.
Possible Solutions:
  • Reposition the work so employees can gain a better access.
  • Redesign the clamp and/or table to allow tilting or rotation for easier worker access.
  • Educate the operator on the importance of maintaining a neutral wrist while performing repetitive motions.
Potential Hazard:
  • Inward and outward rotation of the forearm while gluing can cause injury.
Possible Solution:
  • Educate the operator on the importance of maintaining a neutral wrist while performing repetitive motions.
Top


Pre-Assembly - Frameless Top
A two-man crew assembles various pre-drilled pieces into a cabinet. A baseplate has glue put into all pre-drilled holes and is placed on a table. Pieces with exposed dowels are put into pre-drilled holes and the other pieces are slid into pre-cut slots. A top panel which is pre-drilled and pre-cut is then placed on top and the whole unit is forced together.

Potential Hazard:
  • Using the palm of hand as a pounding instrument can cause injury.
Possible Solutions:
  • Use a rubber mallet to seat materials into their proper position.
  • Provide training to personnel about using tools instead of hands to position items.
Potential Hazard:
  • Abducting elbows and working with elbows above shoulder height can cause injury.
Possible Solutions:
  • Provide steps to allow workers to elevate themselves in reference to the work.
Top


Clamp Operator - Frameless Top
The operator takes the finished products from the preassembly station, seals the cracks, and nails the joints. The operator also applies support boards for backing, then loads the cabinet onto a conveyer.

Potential Hazard:
  • Extending the reach with a raised and abducted elbow and flexed wrist while using finger force in operation of nail gun can cause injury.
Possible Solutions:
  • Reposition work for better worker access by providing a rotating table.
  • Develop a nail gun that utilizes a power grip.
Potential Hazard:
  • Inward and outward rotation of forearm while gluing can cause injury.
Possible Solutions:
  • Educate the operator on the importance of maintaining a neutral wrist while performing repetitive motions.
  • Reposition work for better worker access by using a rotating table.
  • Provide a glue gun with a power grip.
Top


Drawer Rail Installation - Frameless Top
The worker leans over a table with piecework on it and screws drawer rails into place for the frameless cabinets.

Potential Hazard:
  • Extending the reach and bending to get materials from supply bin can cause injury.
Possible Solutions:
  • Place bins of material under the work bench or redesign the work area in another way to minimize reach.
  • Put the materials on a turntable swivel so the work items can be rotated easily to the worker.
Potential Hazard:
  • Using excessive grip force while applying pressure to the screwdriver can cause injury.
Possible Solutions:
  • Provide a collar for the screwdriver handle so the employee can use the fleshy part of the hand to push the tool.
Top


Clip Insertion - Frameless Top
Work is positioned on a horizontal table. The clip is placed and is secured with a screw.

Potential Hazard:
  • Ulnar deviation of the wrist with finger force to activate the power screwdriver can cause injury.
Possible Solutions:
  • Use a power-grip screwdriver.
  • Tilt the work surface.
Top


Small Wall Pre-Assembly - Frameless Top
The worker bends over, picks up the base plate, and installs a another piece of stock into prepared grooves. He then places the piece onto a table and sinks screws to secure the pieces together. After the pieces are secured, they are placed on a conveyer at a low level.

Potential Hazard:
  • Excessive bending at the waist to pick up raw materials and to place the finished product on the conveyer can cause injury.
Possible Solutions:
  • Bring raw materials in at a higher level by providing a lift table and raising the conveyer.
  • Provide a bench or table for assembly nearer to the conveyer to eliminate the carry.
Top


Wall Corner Clamp - Specials Top
A frame is put into the clamp and glue is applied to the joint areas. The top, bottom and two shelves are put into their appropriate grooves. A backing board is placed over the shelves and glued into place. Two side panels are put on and nailed into place.

Potential Hazard:
  • Deviating the wrist while reaching across work surface to apply glue to work surface can cause injury.
Possible Solutions:
  • Have each worker do only one-half of the surface.
  • Educate the operator on the importance of maintaining a neutral wrist while performing repetitive motions.
  • Realign the work for better worker access by providing a tilting or rotating table or other redesign.
Potential Hazard:
  • Deviating the wrist, abducting of the elbow, and working with the elbow above shoulder height while applying force to the trigger mechanism of nailing gun can cause injury.
Possible Solutions:
  • Develop a nail gun that utilizes a power grip.

  • Reorient work for better worker access.

  • Provide steps or platforms to elevate workers in relation to work surfaces.
Potential Hazard:
  • Raising an abducted elbow and pushing with the hand used to support and align materials while nailing can cause injury.
Possible Solution:
  • Provide steps of platforms to elevate workers in relation to work surfaces, tilt work piece, or redesign the work area in another way.
Top
 
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