On This Page:
- Laundry Facility
- | Machine Power Saves Muscle Power
- Improved Staging Leads to Improved Fall Protection
United States Naval Academy
The carts used for transporting the laundry
Emptying the large canvas bags
In 2013, the United States Naval Academy (USNA) Laundry and Dry Cleaning Facility, was redesigned to reduce exposure to ergonomic hazards present during laundry production by installing two dock levelers and an overhead bag system specifically engineered to reduce manual labor and increase performance. This $350,000 project improved working conditions for over 20 people that resulted in a tremendous drop-off in the number of injuries reported and increased worker satisfaction. The new system reduced the musculoskeletal work disorders associated with the upper body lifting and the stress and strains experienced from transporting the incoming and outgoing loads.
At the Naval Academy Laundry Facility approximately 20 lots and 6,300 pounds of laundry are processed each day. A 'lot' contains an average of 15-20 individual bags with each bag weighing up to 40 pounds. In 2013 the Facility processed 1,533,000 pounds of laundry. The process consists of various sorting, washing, finishing and assembly activities.
Originally, bags were received and manually transferred to a conveyor system in the check-in area, where the 40 pound laundry bags were manually removed and emptied of mesh nets and loose items. These items were sorted and color lot tags were stapled to the laundry bags and nets, as well as loose items for re-assembly later. The contents of the bags were then verified against the laundry ticket submitted. Mesh nets were sometimes unpinned to replace loose items; all bags and nets were then secured with a white wire lock-tie and placed on the lower conveyor. This process required a lot of heavy pushing and pulling in awkward postures, repetitive motions, repeated gripping and postural stresses.
The ergonomic hazards associated with the laundry production were lifting over shoulder height, high hand forces from using the large pins and postural stress from leaning forward during the sorting. The sorting area workers spent 8 hours a day pulling the 40 pound laundry bags from the top conveyor. The workers had to twist to pull the bags off the conveyor onto the worktable area. The awkward posture of twisting and pulling the heavy bag from the conveyor exposed workers to areas of considerable stress to the muscles, ligaments, and tendons. Additionally, the pins on the mesh bags that were periodically unpinned and re-pinned required a great amount of force to open and close which eposed workers to ergonomic stressors of high hand forces and a repetitive pinch grip action.
A material handling solution was selected for installation. The material handling equipment provided a more adequate long term solution to reduce and/or prevent ergonomic risks in the laundry facility. The cart dumpers provide exceptional emptying of laundry carts onto sorting tables eliminating manual up front sorting and the heavy lifting from the conveyor to the check-in tables. With hands-free control, high-performance drive units and a 2,000-pound capacity, the cart dumpers increase performance speeds over 30% and improve safety by reducing manual labor.
E-Rail Customer Bag System
The bag table is custom designed to help operators facilitate the initial break-up process and improve operator efficiency by reducing fatigue and excessive bending and twisting. In addition, the laundry bags were redesigned to include a loop/strap that allows each bag to be placed on a hook to be automatically transported onto the overhead rail system.
Finally, the E-Rail overhead bag system provides a fast, efficient automated mechanism to move laundry bags from the bag table, onto the overhead rail system, and then around to the check-in stations. Each check-in station has a call button that allows the check-in worker to call a bag to the work station, then release the contents of the bag onto the station. The worker uses another call button to send the empty bag back. The systems auto-debagger capability automatically releases empty bags from the overhead rail without operator intervention. A workstation level conveyor allows workers to send checked-in and sorted items to the washroom department with minimal effort. These features help reduce the current stress to the muscles, ligaments, and tendons associated with the sorting area by eliminating the awkward posture of twisting and pulling the heavy bags from the conveyor.
Machine Power Saves Muscle Power
Naval Air Weapons Station (NAWS)
China Lake, CA
Before: Pulling super sack (1 cu. yd.) of oily rags onto lift gate
Before: Pushing a plastic hopper, with super sack inside, onto the truck during loading
In 2007, Naval Air Weapons Station (NAWS) China Lake’s, hazardous waste operation was modified to reduce the physical exertion levels and exposure to ergonomic stressors present during the manual material handling (MMH) process by installing and certifying a truck mounted knuckle boom. This modification replaced muscle power with machine power, and therefore reduced the musculoskeletal work disorders associated with heavy and awkward lifting, pulling/pushing, and frequent standing.
NAWS China Lake is the Navy’s largest single landholding, representing 34 percent of the Navy’s total land worldwide. Temperatures in this desert region can exceed 110°F during May to September. NAWS environmental specialists retrieve, categorize, store, and dispose of various hazardous waste materials gathered from across the base using a wide variety of storage containers. They follow strict hazardous waste protocols to prevent unauthorized waste from being disposed of – illegally or accidentally.
The environmental protection specialists are exposed to a number of physical hazards, most notably heavy and awkward lifting, pulling/pushing, frequent standing, and temperature extremes. The physically demanding nature of the profession combined with the temperature extremes, placed the employees at an increased risk of developing additional or more severe WMSDs.
Before: Off-loading truck at storage/containment site
Totes of categorized solvents in storage area.
Environmental protection specialists repeatedly lifted, pulled, and pushed heavy items (e.g. batteries, oil rags, drums) as seen in the photos. The specialists had to lift most items from ground level, and dragged or pushed them onto the lift gate. These items, such as solar and automotive batteries, drums, oil rags (over 2 million pounds a year), solvents, and cubic yard bulk bags (called super sacks), are handled multiple times throughout the disposal cycle.
Additionally, the great expanse of the China Lake property means that items may be retrieved from various staging sites. Once back at the hazardous material processing/staging site, the items are removed from the truck. Some items are weighed while others are quickly categorized/staged for storage, and later moved again for disposal.
After: Truck mounted knuckle boom is being used in operations where other material handling equipment has not been capable of performing the removal of waste items safely.
Thus, the material solution was implemented to reduce the physical exertion levels and exposure to ergonomic stressors. A truck mounted knuckle boom was installed and certified which replaced muscle power with machine power. Although the procedures inherently still require the specialists to sit, climb, balance, stoop, kneel, crouch, crawl, lift up to 50 pounds (or more) and frequently walk and stand; the use of the crane has reduced the severity and frequency of the exposure to ergonomic stressors. A crane now attached to the truck has eliminated much of the excessive materials handling and is capable of retrieving drums, super sacks or bulk bags (used for rags), and other heavy items from any storage surface (pavement or sand).
The successful completion of this project has saved a considerable amount of time and effort during the movement of hazardous waste. The completed project replaces manual effort with machine power and improves the overall safety and health of the environmental specialists.
Improved Staging Leads to Improved Fall Protection
Trident Refit Facility (TRIREFFAC),
Naval Submarine Base, Kings Bay
In 2008, Naval Submarine Base Kings Bay Trident Refit Facility (TRIREFFAC) was redesigned with customized staging for permanent access to the pumps to eliminate the stressors created by overexertion on the workers. This $31,000 project allows workers to work in ergonomic neutral postures, provides access to pumps in a manner that reduces the potential for injury, and reduces the potential for a life threatening fall.
Pump shown in test fixture with the temporary staging surrounding it.
TRIREFFAC provides quality industrial-level and logistics support for the incremental overhaul, modernization, and repair of Trident submarines. It also furnishes global submarine supplies and spare parts support. In addition, TRIREFFAC provides maintenance and support services to other submarines, regional maintenance customers, and other activities as requested.
Side view of test stand.
TRIREFFAC Machinists were subjected to potential injuries due to ergonomic hazards while operationally testing and repairing pumps that circulate water on the Trident Submarines. These pumps support diving and surfacing operations. While being inspected and/or repaired, the pumps are placed on the test stand by a crane. The workers are required to access the entire pump (top, bottom, and sides) and were required to stand on temporary staging that was not conducive for allowing them to perform work in optimal ergonomic postures.
Workers reached and extended their bodies at times as much as four feet, to access bolt threads, wiring, seals, and other components. They also were required to twist and bend their bodies into awkward postures for extended periods of time to perform repairs and tests. These awkward postures resulted in a higher potential for an injury. At times, workers have been observed standing on rails of the temporary staging as well as piping to access components of pumps as they disassemble/reassemble them. This not only was an ergonomic issue, but a fall protection issue as well. The shapes of the pumps are similar to a tower and pot belly that require the necessity for a versatile staging configuration.
Workers who helped install staging: Dan Menard, J.D. Noyes, and Adam Pepper.
These tasks are performed by three to five workers at a time and the same employees work the tasks until the entire pump repair is complete. The task duration is normally 3 days and performed 30 to 40 times per year.
A Mishap Prevention and Hazard Abatement (MP/HA) project was developed to provide an ergonomic solution to this issue. The proj¬ect was submitted through Naval Facilities Engineering Command (NAVFAC) for ergonomic funding in March 2008 for $31,000 to design and purchase customized staging for permanent access to the pumps to eliminate the stressors created by overexertion on the workers. The Navy’s MP/HA Program Team assessed the pump test stand and the potential solution to the ergonomic issues was identified. TRIREFFAC developed a proposed design for permanent staging for the pump stand area. The design was reviewed and approved by the Building 4026 Safety Committee and Facilities Representative. Meetings were held with the potential vendor of the permanent staging and the Navy MP/HA Team reviewed the final design of the staging. The newly acquired staging was installed by TRIREFFAC personnel.