Personnel from each of the services utilize a variety of PPE based on factors such as the operational environment, job description or occupation, and commander discretion. For example, Army and Marine Corps ground combat personnel utilize soft and hard body armor designed to protect against specific small arms, fragmentation, and other unconventional threats, such as improvised explosive devices. Likewise, personnel with aviation based occupations or explosive ordinance disposal responsibilities, and those operating in extreme climates or maritime environments have specific PPE options for their specific assignments. During ground combat operations in Iraq and Afghanistan in the 2000s, Soldiers and Marines typically wore tactical vests or plate carriers with hard armor ballistic inserts, a combat helmet, and other miscellaneous items such as eye protection and gloves. This PPE, added to the other items that personnel typically carry or wear in operational environments (weapon systems, food and water, communications equipment, and other items), cumulatively represent the total load burden on personnel. The total load varies to some degree between the Army and the Marine Corps, and the services use specific load categories for mission-planning purposes. For example, the Army uses three combat loads, fighting (lightest), approach march (mid), and emergency approach march (heaviest), based on a number of factors, including mission duration and purpose, the likelihood of resupply, climate, and other characteristics that affect equipment and supply decisions. Similarly, the Marine Corps uses the following categories for mission and load-planning purposes: fighting (lightest), assault (mid), and sustainment (heaviest). According to Army guidance and Marine Corps documentation, the two services generally use these load parameters as a guide for determining the most appropriate equipment and supply levels required to meet mission objectives. The services each have program offices that develop, acquire, and field PPE and other equipment based on generated and approved operational requirements for Soldiers and Marines. For example, Program Executive Office Soldier develops specifications, and acquires equipment, including PPE, based on capability requirements produced by the Army’s Training and Doctrine Command. Similarly, the Marine Corps Systems Command develops, acquires, and fields PPE and other equipment to address operational requirements developed by the Capability Development Directorate of the Deputy Commandant for Combat Development and Integration. The service program offices typically collaborate with each other and partner with industry providers to research, design, and develop PPE and other equipment. The Army and the Marine Corps have developed requirements for PPE to address operational threats but these requirements contribute to the total load burden on ground combat personnel. The services expect ground combat personnel to wear a combination of equipment developed to meet these requirements, including hard armor plates, soft armor plate carrier vests, and combat helmets, as shown in figure 1. According to Army and Marine Corps program managers, these items individually provide specific functions that together form a protective system for personnel. According to Army and Marine Corps documentation, the current system was initially developed and fielded to address specific threats facing personnel operating in Iraq (Operation Iraqi Freedom) in 2003. Officials stated that the two services conducted capability and threat assessments in this theater to determine how best to mitigate threats without hindering mobility or combat effectiveness. The services have documented these assessments and protection requirements in PPE guidance, technical documentation, and acquisition specifications, which include the size, weight, coverage area, protective standards, and other key parameters for each primary PPE component. These documents standardize PPE expectations and operational requirements for Soldiers and Marines. Officials noted that they are able to change PPE requirements or standards to meet evolving needs, incorporate technological advancements, or modify goals. Additionally, they provide industry partners with specifications needed to develop equipment. While the services have produced individual PPE guidance and technical documentation, officials noted that they jointly develop protection requirements and acquire some of the primary PPE components. For example, the Army and Marine Corps jointly acquired modern hard armor plates and have coordinated on the development and acquisition of the enhanced combat helmet. The two services also have similar standards for the soft armor plate carrier vests, but Marine Corps officials noted that because each service has some unique operational requirements, they developed and acquired this item separately. Army and Marine Corps officials we met with stated that the body armor that was fielded to meet current threats provides significant additional protection when compared with previously available equipment. However, they also noted that providing this level of protection adds significant bulk and weight to the total load on Soldiers and Marines, which could impede mobility and have other adverse effects. Both Marine Corps guidance and Army capability requirements indicate that PPE should provide adequate protection levels without hindering mobility or combat effectiveness. The primary PPE (hard armor plates, soft armor vest, and combat helmet) currently used by both Army and Marine Corps personnel averages approximately 27 pounds (for size medium equipment), and adds to the weight of other uniform items and equipment worn or carried by personnel. The cumulative weight of all uniform items and other equipment expected to be carried or worn by personnel in operational environments represents the total load and can vary according to individual position (e.g., squad leader, rifleman, grenadier) and mission characteristics (see figure 2). According to program managers we met with, the typical total load on personnel has increased since about 2003 based on the incorporation of new PPE systems and other equipment that is designed to enhance personnel performance or protection capabilities. According to 2016 Marine Corps data, a typical load is expected to be approximately 90 to 159 pounds, or an average of 117 pounds, depending on the individual function within the squad. Similarly, Army ground personnel are expected to wear and carry approximately 96 to140 pounds, or an average of 119 pounds, depending on individual roles. These can vary based on individual PPE sizes and other equipment variations. However, the expected totals for Army ground combat personnel generally align with actual load totals ranging from 96 to 151 pounds, reported by personnel recently operating in Afghanistan. However, program officials also explained that excessive loads can have negative effects on personnel mobility, lead to earlier fatigue onset, and exacerbate the risk associated with high temperature operational environments. Army Field Manual 21-18, published in 1990, recommends that the fighting load not exceed 48 pounds and that the approach/march load not exceed 72 pounds. According to program managers, the Marine Corps does not have specific load thresholds or maximums, but documentation identifies that loads in excess of 30 percent of body weight for ground combat personnel increase the likelihood of detrimental performance effects. Medical researchers from the services whom we met with agreed that these are some of the risks associated with substantial combat loads, and stated that they have attempted to correlate load burdens with detrimental performance and increased injury risks. For example, the Naval Health Research Center in San Diego, CA, collected injury data from personnel operating in Afghanistan and Iraq between 2011 and 2013 and concluded that excessive loads may have exacerbated the reported injuries. Service officials said that they are studying these potential effects on personnel performance, but also stated that the available load guidelines could be outdated and not reflective of current PPE systems and other capability enhancing equipment. Additionally, they note that these thresholds may not be appropriate for all personnel and that load thresholds or limits could restrict commander flexibility in the field by potentially impairing their ability to properly outfit personnel to meet mission requirements. Nonetheless, officials from both services stated that they continually seek ways to reduce the weight of PPE and reduce or offset the overall loads on personnel while maintaining operational capabilities and protection standards. Army and Marine Corps officials coordinate through formal and informal working groups that seek to develop and improve PPE. For example, two to four times annually the services hold a Cross-Service Warfighter Equipment Board, which allows Army and Marine Corps representatives, along with members of the other military services, to share developments and advancements made to PPE and other individual equipment. The Army and Marine Corps also participate in the Personal Protective Equipment Capabilities Development Integrated Product Team, an interagency forum that shares information, such as injury data, research and development findings, material developments, technologies, and test methodologies, among key stakeholders involved in PPE development. In addition, the Army and Marine Corps work together on the development and procurement of PPE, such as the hard armor plates and the enhanced combat helmet that meet both services’ needs. Informally, the Army and Marine Corps regularly communicate on a variety of PPE-related research, technology advancements, and planning efforts. Officials from both Army and Marine Corps program offices explained that coordination is mutually beneficial based on similar equipment needs for ground combat personnel. Officials noted that they have collaborated on the development, management, and procurement of current hard armor plates since their inception in the early 2000s. Additionally, in August 2016 we observed a Marine Corps-sponsored industry event focused on the next iteration of the enhanced combat helmet, where an Army engineer participated and shared with vendors the Army’s perspective on weight reduction priorities for the helmet. Army and Marine Corps officials stated that they collaborate with vendors to gather input for the development of PPE. Army and Marine Corps program managers said that when developing or improving PPE and other equipment, they prioritize protection and operational capabilities, and that they have overarching goals of reducing weight, and improving form, fit, and function of equipment. These overarching goals have led to some improvements and reductions in the weight of some PPE. For example, the Army and Marine Corps have made updates and redesigned aspects of their respective soft armor vests, which according to program managers have resulted or will result in weight savings of up to approximately 40 to 50 percent, or about 6 to 7 pounds when compared with previous versions. In addition, according to Marine Corps documentation, the service is incentivizing industry partners to produce lighter equipment and systems by incorporating weight reduction as a part of the source selection process for the enhanced combat helmet.