Hand Arm Vibration
Powered hand tools allow heavier work to be performed with greater speed and efficiency. However the improper design and use of powered hand tools can contribute to Work-Related Musculoskeletal Disorder (WMSD) injuries. Vibrating tools can cause vascular spasms or a constriction of blood vessels in the fingers, which then appear white or pale. Vascular constriction may lead to numbness and swelling of hand tissue, with a loss of grip strength. Vibration-induced white finger, also known as "Raynaud's phenomenon," and hand-arm vibration syndrome (HAVS) cause tingling, numbness, or pain that can be brought on or intensified by exposure to cold. There are preventive actions that can be taken to reduce the impact of vibration:
- Reduce the number of hours or days vibrating tools are used in accordance with the American Conference of Governmental Industrial Hygiene Threshold Limit Values.
- Arrange tasks to alternate use of vibrating and non-vibrating tools.
- Schedule tool maintenance so tools remain sharp, lubricated, and properly tuned.
- Use gloves with vibration-damping materials in the palms and fingers. Ensure workers keep warm at work, especially their hands. To be effective, gloves should fit, be full finger, and comply with ANSI S3.40-2002 or ISO 10819 standards.
- Use tools with vibration-damping handles.
- Keep hands warm and dry.
- Avoid using tobacco or stimulant drugs that may restrict blood flow to the skin by as much as 40 percent.
The DCPH-A Ergonomics Program can assesses the injury risk associated with exposure to HAV. Through vibration analysis, the severity and probability of injury for crew positions can be assessed and a Risk Assessment Code (RAC) assigned.
There is a free downloadable Fact Sheet called "Selecting the Proper Powered Hand Tool can Make Your Work Safer and Easier"
Whole Body Vibration
A vehicle's movement causes mechanical energy in the form of vibration, which propagates through the vehicle's structure. In turn, the vibration of the vehicle is transmitted to the occupants through various contact points such as the seat and floor. This vibration, known as Whole-Body Vibration (WBV), can affect the health and readiness of the soldiers as well as civilians. The relevant literature of the effects of long-term high-intensity WBV indicates an increased health risk to the lumbar spine and the connected nervous system of the segments affected. The USAIPH Ergonomics Program assesses the injury risk associated with exposure to WBV. Through use of a program called JOLT, the severity and probability of injury for crew positions can be assessed and a Risk Assessment Code (RAC) assigned. System developers involved in designing or conducting WBV tests may obtain the most recent guidance describing formatting of test data by contacting the Health Hazard Assessment Program.
