Military Nondestructive Testing: Safety Precautions
Nondestructive testing is a critical component of maintaining mission readiness across all branches of the military. The various methods of nondestructive testing—ultrasonic, eddy current, magnetic particle, radiographic, liquid penetrant, laser testing, and leak testing—allow military personnel to inspect infrastructure, vessels, vehicles, and weapons systems for flaws, corrosion, and other defects which could lead to failure and endanger the lives of servicemen and servicewomen. As such, following nondestructive testing procedures established in military codes, regulations, and orders is in itself an important safety precaution.
While nondestructive testing works to mitigate equipment failure hazards, performing nondestructive inspections can, in some cases, expose military personnel to additional hazards related to the testing equipment or inspection environment. In order to safely and effectively perform their inspection duties, military personnel performing nondestructive testing must be aware of any hazards present during inspection, as well as the appropriate safety precautions necessary to mitigate them.
Where to Find Safety Precautions for Military Nondestructive Testing
Information on safety precautions for military NDT are provided by two primary sources: the equipment manufacturer and the military itself. Military personnel are obliged to follow directives issued by the military regarding testing procedures and safety precautions. Often, military directives include orders to follow manufacturer’s recommendations regarding personal protective equipment and other safety precautions.
Each branch of the United States military has issued specific safety regulations relating to nondestructive testing procedures. Broad safety regulations can be found in documents such as the Air Force Manual 91-203. More specific safety regulations can be found in the relevant Army, Navy, and Air Force Technical Manuals for each different method of NDT used by the military. Certain testing applications, including testing of various weapons systems, are regulated by even more specific directives, which can be found in Air Force Technical Orders, comparable Army documents, OPNAV instruction 4790.2, and manuals specific to the weapons system being tested. Safety information for specific models of testing equipment can be obtained from the equipment’s manufacturer.
Supervisors are responsible for understanding and implementing current safety regulations prescribed in military code, and for ensuring that their technicians are properly trained and certified in NDT/NDI procedures. In addition, technicians must follow the orders of base bioenvironmental engineers regarding personal protective equipment. Before beginning work on any NDT project, personnel should review a current Job Hazard Analysis to identify all possible hazards and their relevant mitigation techniques.
Safety Precautions for Common NDT Equipment and Procedures
Certain nondestructive testing methods used by the military, such as ultrasonic or eddy current testing, are almost entirely benign and do not pose a hazard to testing personnel. However, other NDT techniques involve potentially harmful exposure to ultraviolet radiation, ionizing radiation, or X-rays.
To prevent damage from ultraviolet radiation, appropriate filters and lenses must be used whenever a black light is in operation. Due to the potential for serious burns resulting from skin contact, personal protective equipment must be worn, and contact with the black light bulb should be avoided. Exposure to X-rays or ionizing radiation can result in serious health problems. Such exposure must therefore be prevented by using proper engineered and personal protective equipment. Personnel dosage must be monitored and limited according to the relevant regulations, including 21 CFR, Parts 1020.30 through 1020.33, OSHA 1910.1096, Ionizing Radiation, AFMAN 48-125, Personnel Ionizing Radiation Dosimetry, and AFI 48-148, Ionizing Radiation Protection.
In addition, compressed gasses such as sulfur hexafluoride, acetylene, and nitrous oxide can commonly be found in NDT laboratories. These must be stored, handled, labeled, and disposed of properly to prevent mishaps and accidents.
Safety Precautions Related to NDT Inspection Environments
Finally, even if inspection techniques and equipment are themselves benign, the environments in which testing is conducted may pose serious health and safety hazards. Environmental hazards are dynamic, changing from job site to job site, and even from day to day. Performing a conscientious job hazard analysis to identify environmental hazards is necessary whenever location or conditions change.
Certain environmental hazards are more common than others, and various environmental hazards may overlap on the job site. Chief among these include the presence of flammable gases or vapors, heights, and confined spaces. Of course, conventional hazards such as slips, trips, and falls remain extremely common on all job sites and should be mitigated by maintaining the cleanliness of the sites and the removal of objects which may cause missteps.
When working in environments with flammable gases, technicians must be certain to use equipment rated for electrical safety according to the requirements of National Fire Protection Association 70, National Electrical Code. Failure to follow these requirements can increase the risk of explosion.
NDT technicians working at heights over four feet, or above a hazardous location, must wear appropriate fall protection equipment, as prescribed by OSHA’s standards for general industry.
If confined space entry is required to perform an inspection, then all engineered, administrative, and personal protective controls must be strictly adhered to. Guidance for confined space entry is informed by OSHA Standards 29 CFR 1910.146, General Industry, 29 CFR 1926.21, Construction Industry, and US Army Corps of Engineers Safety and Health Requirements Manual EM 385-1-1.
Despite stringent safety precautions for military nondestructive testing, some environments remain inherently dangerous. By equipping personnel with powerful and efficient testing equipment, supervisors can help their technicians perform their work more quickly, limiting exposure. Lightweight equipment helps reduce fatigue—and the consequent occurrence of mental errors—while also providing ergonomic solutions for technicians performing inspections in hard-to-reach or awkward positions. Mechanical systems such as scanners with motor controls and weld crawlers can also reduce worker exposure to environmental and ergonomic hazards.
Nondestructive testing is an essential component of military readiness across every branch of service. Depending on the method of testing, and the testing environment, certain safety precautions are required by military code. Following regulations on safety precautions isn’t just necessary—it’s wise.
Zetec’s designers are industry-leading experts in ultrasonic and eddy current technologies, and we can help you navigate any of our NDT testing solutions or devices.