The Navy cares deeply about protecting the safety and health of its greatest resource - its people. In today's workplaces, there exist many potentially serious occupational hazards. Some hazards, like noise-induced hearing loss and heat stress, are well known, heavily reported, and well documented. Much less is known about other workplace perils, which can produce serious, irreversible, and unsuspected diseases. Occupational Vibration, affecting eight to ten million people in the U.S. alone, is one of these lessobvious workplace hazards. Because Navy Leadership is concerned about the safety and health of its military and civilian workers, they are working hard to address this under-recognized occupational health problem through acquisition of safe, cost-effective, and performance-improving designs and equipment. This section of the Acquisition Safety website addresses the vibration issue uniquely and in depth. Included are the potential health effects of uncontrolled vibration and ongoing efforts to control this risk to Navy personnel. Also provided are best business practices and technical assistance for acquisition (research, development, design and procurement) of designs and equipment that will maximize productivity and operational effectiveness while protecting operators and maintainers of this equipment.

Continuous exposure to excessive levels of vibration can cause irreversible damage to the human body. Workers who continually interact with machinery are affected to some degree by occupational vibration. Vibration exposure can be caused by use of poorly designed equipment and tools, which do nothing to attenuate vibration exposures. Two different types of vibration exposures - segmental (hand/arm) and whole body - affect the health and safety of some eight million U.S. workers. What Is Vibration?

A common category of segmental vibration exposure, affecting two million workers, is called Hand-Arm Vibration (HAV). This type of vibration exposure is caused by the regular use of vibrating pneumatic, electric, hydraulic, or gasoline-powered hand tools. Excessive HAV exposure can produce an irreversible condition of the hands called Hand-Arm Vibration Syndrome, or HAVS. (Click here to learn more about HAVS.)

Workers using manual grinders, swing grinders, cutting tools and similar equipment may be susceptible to HAVS. Table1 shows HAV exposures of U.S. Navy personnel.

A second type of vibration exposure, affecting six million workers from "head-to-toe," is called Whole-Body Vibration, or WBV. Whole-Body Vibration may occur in workers who regularly operate trucks, buses, heavy equipment, forklift trucks, trains, helicopters, rotary and fixed wing aircraft, ships, etc. Both health and safety problems may arise from WBV. The body becomes tuned to and amplifies some WBV frequencies. The safety concern is that under these circumstances operators can experience a loss of vehicle control due to vibrations forcing their hands away from the steering wheel and other controls. Table 2 shows potential WBV exposures of U.S. Navy personnel. (Click here to learn more about WBV.)

Disabled workers suffering from HAVS and/or WBV-related degenerative disc disease are not as productive as employees who are not so affected. Uncomfortable workers may subvert built-in safety mechanisms that they feel hinder them from performing their jobs quickly and easily, for example by using ill-fitting anti-vibration gloves, hearing protection,etc. Additionally, pain may cause fatigue and loss of concentration. These factors can contribute to workplace accidents, which can mean personnel injuries, even deaths. Aside from costs for treatment and rehabilitation, injuries mean lost time and productivity on the job. Accidents also result in time and material costs when equipment has to be repaired or replaced and operations are delayed or cancelled.

Acquisition managers and design engineers should continue to consider the potential negative impact of excessive vibration on mission performance, direct acquisition expenditure (acquisition life cycle cost), delivery schedule, and total ownership costs (TOC = lifecycle cost plus infrastructure support costs). Optimal use of existing technology can reduce risk factors and produce a superior product while protecting the safety and health of system operators/maintenance personnel. Prevention of vibration hazards has high return on investment in avoided workers' compensation for all areas of acquisition - during construction, maintenance, and disposal.

Acquisition managers and design engineers are strongly encouraged to use and purchase, as applicable, "air ride" seats for Whole-Body Vibration situations requiring effective attenuation in the vertical (up-down) direction, fore-aft (front to back) direction, and sway (side to side) direction.

This technology has been highly developed and used in the transportation industry. Similarly, for Hand-Arm Vibration maximum safety, health, and performance requirements, acquisition managers are strongly encouraged to purchase AntiVibration, ergonomically designed power tools. These tools have numerous applications commonly found in both ship and base installations. Equally encouraged is the purchase of full-finger protected AntiVibration Gloves, which meet or exceed domestic/international standard: ANSI S3.40-2002 - ISO 10819.

Potential Effects of Excessive Equipment Vibration on Acquisition Projects

Whole Body Vibration (WBV) - Equipment that creates excessive vibration can adversely affect the programs for building and buying equipment and vehicles and the life cycle costs for their operation. Vibration transmitted to operators and other occupants can impair their comfort, performance, and visual acuity and in extreme cases, even the ability to control a vehicle or aircraft. Whole body vibration in the range of 4 Hz vertical and 1-2 Hz side to side will create loss of control for vehicle operators. This is a resonant frequency (the range of motion is increased rhythmically with this frequency) and operators will be literally unable to control the vehicle.

Designs that avoid this pitfall will be more effective and operate at reduced cost and risk. Excessive vibration is also likely to degrade equipment and can be an indicator of wear or impaired equipment condition. Fortunately, the control measures often have relatively low costs. For example, vibration control seats for vehicles are available for $400 to $500 each. Good vibration control is a hallmark of well-designed equipment in applications ranging from ventilation systems to engine mounting.

Control of vibration and noise is considered mission essential for many ships and certain land-based equipment because it reduces the vulnerability of their detection by the enemy. Lack of attention to vibration and noise control in the design phase can result in products that do not meet performance requirements and require costly re-design and schedule delays. This was the case for a minesweeper (ship designed to detect mines) that required improved mounting (isolation) of its engines, acoustical insulation, and other controls to reduce transmitted vibration to an acceptable level. The immediate impact on the first ship of this class was increased cost and delay required for re-engineering. But, the end result was a much quieter vessel that was healthier and safer to operate.

Hand Arm (Segmental) Vibration (HAV) - Tools and processes that create excessive hand-arm vibration to users (workers) may have an impact on production and maintenance, which may impact schedule or cost. Products may be more costly to produce and maintain due to effects of HAV on skilled production and repair workers. Aircraft (especially airframes) and ship production include many processes that may create risks for hand-arm vibration in manufacturing workers. This is also a design and production issue related to quality control. For example, better castings will reduce the need for rework in the cleaning/finishing department where excess material is ground off.

Better tools and work process layout almost always yield results in productivity. This is particularly true in applications such as the aircraft production industry where assembly layout and tool selection can reduce worker exposure to awkward postures and hand-arm vibration while improving efficiency. Maintenance and repair costs can be influenced by measures such as selection of low-vibration tools and ongoing tool and equipment upkeep.

Table3 summarizes the potential effects of vibration on acquisition projects.

Noise and Vibration Control in Design

•  DoD Instruction 5000.2 and SECNAVINST 5000.2D require evaluation of health and safety hazards for all acquisition programs. Relevant sections include: DoD 5000.2 section; 4.3.7.3/SECNAVINST 5000.2D Part 7 section 7.2.1 ("PMs and sponsors shall address HSI throughout all phases of the acquisition process").
•  Ergonomic and vibration related sections of OPNAVINST 9640,
•  OPNAVINST 5100.23 (Series) and DoD Instruction 6055.12 (Series)

A discussion of control of hand arm vibration in Navy workplaces is provided in Protecting Our People from Bad Vibrations (Success Stories section of this website).

•  Assessing environmental and safety regulations that will impact the weapon system throughout its lifetime.
•  Identifying safety and health risk factors identified by review of legacy systems and proposed designs along with formal documentation of any decisions to accept those risks.
•  Taking action to reduce safety and/or health risk factors. Note: Protective equipment and warning signal/notices are considered the least effective measures and are not considered design controls.

Role of Personal Protective Equipment in Vibration Control

Personal protective equipment alone is not hazard abatement relative to the acquisition process.  OSHA and supporting Navy Instruction OPNAVINST 5100.23 Chapter 5 require that designs abate hazards and allow interim use of protective equipment only where design feasibility and cost considerations preclude exclusive use of engineering controls. System safety and associated hazard abatement tracking (Mil Std 882) also do not consider personal protective equipment as abating a hazard, and require a hierarchy of controls beginning with engineering controls.

Use of gloves meeting ISO 10819 certification criteria for reduction of transmitted vibration is an important mitigating measure in control of vibration transmitted to the hands/arm. Certified anti-vibration gloves must be used in combination with selection of tools and processes designed to minimize or avoid vibration, worker education, medical evaluation and overall process management in order to reduce the risk of hand-arm vibration syndrome.

Use of anti-vibration gloves certified by a third party is essential to be assured of suitable protection. Information on HAV standards is provided in the Vibration Resources section, "Further Reading on Vibration and Vibration Control." Because the Hand Arm Vibration disease begins in the fingers, and because maintaining warm, dry hands to protect against vasoconstriction is essential; products described as "half finger" gloves do not meet ISO/ANSI standard for anti-vibration products and should not be used as "anti-vibration" gloves.

Two certified, US manufactured products have been given global (national stock numbers) and should be available within the Federal supply system.  Click here to see a brochure describing these products.

Additionally, one category of certified anti-vibration glove has been made available through GSA Advantage (see the Vibration Resources section) for product information. The GSA advantage process allows vendors to provide products which do not have national stock number (NSNs) to be marketed with the support of the Federal system.  It is a more rapid process.

Defense Safety Oversight Council-Sponsored Projects
A project to provide improved power hand tools and certified anti-vibration gloves was sponsored by the Defense Safety Oversight Council's Acquisition and Technology Task Force with the support of the Government Services Administration and National Institute for Occupational Safety and Health.  A report was presented to the 3rd American Conference on Human Vibration in June 2010. A focused one-year project extension has been funded and initiated in November 2010.

Note: Distribution of this information does not constitute product endorsement for a particular vendor or manufacture. However, the product certification has been independently verified.

Other certified anti-vibration gloves are available through a limited number of vendors. Anyone ordering such products should ask the vendor to confirm ISO 10819 certification, as well as considering other performance and comfort factors.

Individual fit and worker preferences as well as adaptation to particular work tasks are key factors to consider in use of any protective equipment. However, if the products described in this material are suitable for your application, their use should be strongly considered for processes which expose workers to high levels of hand-arm vibration.

Vibration-related diseases are not new. HAVS was described in U.S. literature as early as 1918, and WBV problems became apparent around 1945. However, vibration-related diseases are often mistaken for other medical conditions and appear to be under reported in the medical literature. In addition, vibration measurements are difficult to perform at times because of the variability of the exposure, complexity of the measuring equipment, and techniques and skill required by the evaluator. The Navy recognizes these problem areas and has sponsored courses that include training on vibration for industrial hygiene and medical personnel. The greatest challenges are vibration recognition, disease prevention, and minimizing vibration exposures. Vibration induced disorders can be minimized by early intervention. The American National Standards Institute (ANSI) and American Conference of Governmental Industrial Hygienists (ACGIH) have developed recommended standards and guidelines, respectively, for exposures to both whole body and segmental vibration. These criteria identify recommended maximum exposures to vibration. The Navy faces the continual challenge of finding better and improved vibration-reducing materials and technologies that meet these guidelines and standards and can be incorporated into ships and shore facility designs during the acquisition process.

Protecting Navy workers from hazardous Whole-Body Vibration means minimizing vibration source generation together with providing a protective whole-body cocoon for exposed workers with follow-up by regularly monitoring the vibration environment while employing sensible work practices. These include:

•  Purchasing vehicles with suspension systems that minimize vibration and, where possible, mechanical isolated/floating cabs;
•  Purchasing "air-ride seats," (seats provide a protective cushion of air) for both drivers and passengers, as applicable, either as part of an original equipment manufacturer purchase of vehicles and/or;
•  Removing non-protective driver's seats from existing vehicles and replacing them with air-ride seats;
•  Using air-ride seats for some non-vehicle WBV applications such as hovercraft at sea and in fixed work station situations where the floor vibrates due to functioning equipment processes;
•  Adding or designing 'isolators' under machinery to reduce source vibration in some fixed facility situations. This would include foundation mounts that prevent vibration transmission to other structures;
•  Incorporating shock mount stand plates, chairs, and vibration dampened controls in acquisition design stages;
•  Using good work practices, which include workers taking periodic rest breaks for every one to two hours of continuous WBV exposure and not lifting objects immediately after prolonged WBV exposure, leaving the vehicle using simple egress motions, walking around for a few minutes, and performing other non lifting tasks before attempting any lifting tasks;
•  Making workers aware of signs and symptoms of WBV-induced back problems and the need to see their safety managers and health care providers if signs and symptoms occur.

Protecting Navy workers from hazardous Hand-Arm Vibration is multifaceted and begins with minimizing vibration source generation together with providing effective personal protection for exposed workers, regularly monitoring the vibration environment, and employing sensible work practices. These include:

•  Purchasing and using only power tools, which are designed to reduce vibration (called AntiVibration, or A/V) and reduce musculoskeletal injuries.
Important Note: An ergonomically designed power tool, does not mean the tool has reduced vibration attributes and vice versa; thus power tools which are either A/V designated alone or ergonomically designated alone are not the best choice. The former solution alone, while reducing HAV, can leave tool workers at possible risk for Carpal Tunnel Syndrome, CTS (syndrome of the median nerve and flexor tendons of the hand and wrist). The latter solution alone, while reducing CTS, can leave tool workers at risk for irreversible HAVS.
•  Not purchasing or using so-called "vibration reducing tool wraps" which are merely tool handle sleeves that attempt to reduce vibration of conventional power tools. These wraps are generally ineffective and do little to reduce vibration. They also pose an added problem by increasing tool handle diameter, which can possibly lead to cumulative trauma disorders (CTDs) of the forearm, elbow, and shoulder.
•  Using only full-finger protected AntiVibration gloves, which meet or exceed the following A/V Glove standard: ANSI S3.40-2002 - ISO 10819. AntiVibration gloves:

•  Must be full-finger protected (no exposed fingers);
•  Must fit well (allowing maximum finger tactility and proper grip);
•  Must keep the fingers and hands warm and dry (to avoid cold-triggered HAVS attacks).

•  Using good work practices, including:

•  Letting the power tool do the work;
•  Holding the power tool with the lightest grip possible consistent with safe work practices;
•  Keeping hands and body warm and dry;
•  Not smoking (nicotine, cold, and vibration all constrict blood vessels impeding circulation).

•  Maintaining power tools & associated implements in good condition. Otherwise, vibration levels will eventually increase. Thus, regularly scheduled HAV tool monitoring is necessary.

•  Making workers aware of HAVS signs and symptoms and the need to see their safety managers and health care providers if signs and symptoms occur.

Further guidance for users of anti-vibration gloves is provided in DoD Ergonomics Working Group News - Guidance for Users of Anti-Vibration Gloves and in the Resources section below.

•  Further Reading on Vibration and Vibration Control
•  Occupational Vibration Videotapes
•  Occupational Vibration Guidelines and Standards
•  Occupational Vibration Training & Education
•  DoD and Other Safety Websites Dealing with Vibration

Further Reading On Vibration and Vibration Control

Health and Safety Executive (HSE) 
The European Union has developed regulations for evaluation and management of whole body and hand arm vibration. The United Kingdom's Health and Safety Executive (HSE) (English counterpart of OSHA and NIOSH) provides information on the standard and cost-effective recommendations for control of occupational exposures in varied industries and operations.

Hand Arm Vibration — Just Facts, July 2008  
In the U.S. alone about 2.5 million workers are exposed daily to Hand-Arm Vibration [HAV] from the power tools they use on their jobs.

Hand-Arm Vibration Standards: The New ANSI S2.70 Standard 
Article by Donald Wasserman, MSEE, MBA describing HAVS, the history of hand arm vibration safety standards, and the background, terminology, and provisions of ANSI Standard S2.70.

Certified Anti-Vibration Gloves 
Photos and sources of certified anti-vibration gloves.

GSA Advantage Certified Glove
One category of certified anti-vibration glove has been made available through GSA Advantage (see www.gsaadvantage.gov). The GSA advantage process allows vendors to provide products which do not have national stock numbers (NSNs) to be marketed with the support of the Federal system. Note: Distribution of this information does not constitute product endorsement for a particular vendor or manufacture. However, the product certification has been independently verified.

Procurement Criteria to Minimize Hand-Arm Vibration Risk 
Description of project to identify criteria and procurement guidelines for anti-vibration gloves and power hand tools which will eliminate or at least reduce workplace hand-arm vibration injuries.

A Guide to Users of Anti-Vibration Gloves
From the DoD Ergonomics Working Group Newsletter of October 2009

High Speed Craft Human Factors Engineering Design Guide  
Designed for Naval Architects, Academia, Procurement Agencies, Regulatory Bodies, and Human Factors Subject Matter Experts (see page 3).
Source: High Speed Craft Human Factors & Craft Design web forum  

Hand Arm Vibration Threshold Limits," DoD Ergonomics Working Group News, Issue 55, August 2006  
Measuring exposure levels of hand-arm vibration is a complicated process. An instrument called an accelerometer is used to measure the vibration present from a power tool and then converts it to a proportional electrical output. This output signal is modified to account for the range of frequencies that are particularly harmful to the hand and arm.

NIOSH Power Tools Database
NIOSH recently released a Power Tool Database that can be used to find such information as sound power levels, sound pressure levels, and downloadable exposure and wave files related to commonly used power tools.

"Occupational Vibration Exposure-Ch. 4" in Physical & Biological Hazards of the Workplace, 2nd.Ed. [P.Wald & G. Stave, Eds.], Wiley Pub., New York, 2002.

"Occupational Vibration-Ch. 105 in Patty's Toxicology, 5th.Ed [E.Bingham, B. Cohrssen, & C. Powell, Eds.], Wiley Pub., New York, 2001.

"Hand-Arm Vibration: A Comprehensive Guide for Occupational Health Professionals-2nd.Ed., P. Pelmear & D. Wasserman, OEM, Medical Press, Beverly Farms, MA, 1998. [ISB 1-88-3595-22-3]

"Musculoskeletal Disorders & Workplace Factors", NIOSH, Pub. #97-141, Cinti., 1997.