Staff Views
L.E. Forum

Ergonomics and Safety in Law Enforcement
Fabrice Czarnecki and Ira Janowitz

From Clinics In Occupational and Environmental Medicine

Volume 3, Issue 3, Pages 399-417 (August 2003)

In law enforcement, ergonomics and safety issues are approached with three priorities that are essential for that occupation and sometimes are oppositional: public safety, officer survival, and avoidance of litigation. Police officers serve and protect the public, insure their own safety, and make sure that their actions do not create litigation against themselves or their agencies.

The equipment used by law enforcement to support these priorities has to be effective, safe, and reliable. The reliability sometimes is overlooked. During a period of 12 months, a large municipal police department experienced failure of its ammunition, handguns, ballistic vests and automated external defibrillators. Once equipment is selected and issued, it has to be evaluated constantly for its efficacy, reliability, risks for acute or chronic injuries, and associated risk for litigation.
Training safety [Return to Article Outline]

Training causes significant mortality and morbidity among law enforcement officers. Proper equipment and safety procedures should be used to prevent training injuries. Between 1992 and 2001, nine officers died in training from accidental shootings in the United States [1]. Several officers died from falls, overexertion, and other causes during training sessions.

Between 1990 and 1997, 612 incidents with casualties during tactical operations were reported to a database operated by the Casualty Care Research Center at the Uniformed Services University of the Health Sciences. There were 1529 deaths [2] . The highest risk for injury to tactical teams was found during training, when the casualty rate per 1000 man-missions was 8.8, compared with 5.5 during hostage rescue and 4.6 during high-risk warrant operations.

Live firearms training

The usual procedures for live firearms training involve one or several range officers who issue commands on a firing line. If the ratio of range officers (or instructors) to shooters is appropriate and firearm safety rules are stressed, the risk for accidental gunshot wounds should be low. One instructor for up to five shooters is an optimal ratio for static shooting. For dynamic exercises, such as shooting on the move, the ratio should be one instructor for one shooter. A more common problem is backsplash, when metallic debris from the bullet or from a metallic target hits a shooter. Injuries caused by backsplash range from minor skin abrasions to serious lacerations requiring surgical repair. Respecting minimal distances from the target, using training frangible ammunition, and using protective equipment minimize the risk for backsplash injury. Frangible ammunition disintegrates into a fine powder when hitting a hard surface. It allows officers to train with live firearms in close-quarters combat in realistic settings, where the shooting distance is across a room.

The mandatory protective equipment that is worn by shooters includes eye protection, hearing protection, and appropriate clothing. The Occupational Safety and Health Administration (OSHA) requires appropriate eye or face protection when exposed to eye or face hazards from flying particles  [3]. Typically, shooters wear wraparound eyeglasses (Fig. 1) . Goggles are also acceptable. Regular eyeglasses or sunglasses should be fitted with sideshields, as OSHA requires side protection. Some wraparound glasses fit over prescription eyeglasses. Protective eyeglasses should comply with the American National Standard Practice for Occupational and Educational Eye and Face Protection (ANSI Z87.1-1989 standard).


Fig. 1. Hearing and eye protection for firearms training. From left to right: electronic earmuffs, wraparound eyeglasses, custom silicone earplugs, two different types of foam earplugs

Hearing protection can be provided by earmuffs and earplugs, which are graded by the noise reduction rating (NRR). The NRR typically ranges from 21 to 27 dB for reusable earplugs, 28 to 33 dB for foam earplugs, and 17 to 31 dB for earmuffs (see Fig. 1 ). Officers should wear earplugs and earmuffs during firearms training, to maximize hearing protection. Electronic earmuffs amplify noise up to a threshold level (around 80 dB) and help to hear commands on the range. Electronic earmuffs are recommended for frequent shooters, including firearms instructors and tactical team members, in conjunction with earplugs. Custom-made silicone earplugs are available and are preferred by some shooters for their comfort. Officers should be careful about hearing protection when shooting indoors or when shooting short-barreled carbines.

The main purpose for headgear and clothing for shooters is comfort, but these items also could increase safety. Casings ejected by firearms are hot and could burn and distract shooters. A baseball cap or a hat with a wide brim should be used. Long pants and long sleeves offer protection against hot brass and the environment. Warm clothes are indicated if shooting in a cold environment, because most range training is fairly static. Officers may choose to wear ballistic vests during firearms training.

A first aid kit should be readily available on each range. At the minimum, a kit should contain the following items:

  • Two tourniquets

  • Two trauma dressings

  • Two pairs of gloves (latex or nitrile)

  • Two rolls of conforming gauze

  • Adhesive bandages

Optional items, depending on the environment and on the level of medical training of the range officers, include the following:

  • Automated external defibrillator

  • Pocket mask

  • Nasopharyngeal airways

  • Splints

  • Elastic wraps

  • Nonadherent dressings

  • Bandage strips

  • Gauze pads

  • Tape

  • Space blanket

  • Emergency medical technician (EMT) shears

  • Cold compresses

  • Sunscreen

  • Insect repellent

  • Acetaminophen, ibuprofen, aspiring

  • Antibiotic ointment

  • Antiseptic solution

  • Saline drops

Police agencies should develop policies to address medical emergencies that may occur on the range. Besides accidental gunshot wounds and backsplash, other possible medical emergencies at a police firing range include blunt trauma (falls); environmental injury (hypothermia, heat exhaustion, bee sting, poison ivy); cardiac disease, especially during intense physical training; and other general medical emergencies. Firearms instructors should have some first-aid training. Ideally, an EMT should be on staff. Ranges commonly are located in remote areas. Access to emergency medical services (EMS) can be an issue, and its procedures, such as when and how to call for a medical evacuation helicopter, should be addressed in advance. Several means of communication should be available to call for help. The location of the nearest hospitals and trauma centers should be known.

Simulation training with firearms

Most of the recent training deaths of officers occurred during simulation training. Simulation is a valuable part of the training: It allows officers to experience realistic fights during force-on-force scenarios. During simulation training, firearms are rendered safe and are used to shoot blank or marking rounds or are kept empty for dry firing. Blank rounds create a concentrated blast of hot gases that can be deadly at close range. Police officers have been injured seriously by blank rounds in training; however, most accidental shootings in training happen when a loaded weapon is brought in by mistake. Typically, an officer leaves the training area and loads the gun. He or she returns to the training environment, forgetting that the gun is loaded. Another common mistake happens after the end of the simulation exercise, when the guns have been loaded. An officer asks a question about the exercise, and the instructor offers to do another demonstration of the technique, forgetting that the gun is loaded.

Law enforcement agencies should implement strict guidelines to prevent these tragedies. No live weapons and no live rounds should be present in the training area. Training officers should go through a simulation instructor's course. Safety officers should search officers for live rounds and weapons and possibly use metal detectors. Firearms should be inspected immediately before the exercise by the safety officer and the student to make sure that the firearms are loaded with training rounds. The training area should be closed, and no interruption should be allowed. Students and instructors are notified when training is completed and when they can have access to live weapons, for example: No more practice, no more demonstration, you now carry live weapons.

Real firearms should be avoided whenever possible, unless they are fitted with special devices that allow only blanks or marking rounds to be fired and are marked with a special color (usually red). Real firearms should not be used for dry firing during simulation and should be replaced with dummy guns for exercises that do not require shooting. Officers should wear hearing and eye protection if guns are fired. Groin, throat, and neck protection is mandatory if marking rounds are used. Ballistic vests are recommended. A medical kit, similar to the range medical kit described earlier, should be available. Instructors should be trained in first aid and have plans and communication means to contact EMS.

Defensive tactics training

Defensive tactics is the art of empty-hand combat. Law enforcement officers use defensive tactics to control (restraint techniques) and disable subjects (impact techniques) and to defend themselves when attacked (blocking, falling, and rolling techniques). Firearm retention and disarming, knife defense, handcuffing, and impact weapons usually are added to the defensive tactics curriculum. Wall padding and mats with no gaps between them can reduce injuries in defensive tactics. Shoes should be worn while working on mats. Live weapons should be avoided whenever possible and replaced with dummy weapons. Plastic guns and knives are preferred during more dynamic exercises. Dummy aluminum guns and knives might be preferred in other training exercises, because they feel more realistic and are less likely to break, chip, or cause lacerations.

Handcuffing training uses real, metallic handcuffs. It can be painful and could cause nerve damage. Overly tight handcuffs have been found to cause temporary and permanent neuropathies [4,5]. To prevent nerve damage, wrist neoprene support bands could be used, and handcuffs should not be too tight.

Simulation training in defensive tactics lets officers experience the stress of a real fight and shows them how to apply successful techniques under realistic conditions. To achieve this goal, officers playing the attackers wear special protective suits (Fig. 2) . Commercial training suits are generally not appropriate for full-contact fighting and need to be modified for added protection and mobility; however, there have been improvements in these suits (P.J. Messina, personal communication, 2003). Training suits have to provide protection against impacts, adequate mobility, and peripheral vision while minimizing dehydration and heat exhaustion. At the Modern Warrior Defensive Tactics Institute, training suits are supplemented with ice packs on the chest, on the back, and around the neck to prevent heat exhaustion. Additional support is added to the back of the neck to prevent whiplash injuries while preserving the mobility of the neck. Officers playing the attackers should have special training and frequently should rest and hydrate during simulation training. They also should wear mouth guards. Several monitors are needed to direct the fight, keep the officers safe, and check the protective equipment. The floor, walls, and dummy weapons should be padded. The trigger guard of the dummy guns should be removed to prevent finger injuries. To keep the fight realistic, the officers do not wear protective equipment. The duration of a fight should be limited to 60 seconds. Code words should be used to stop the fight if anybody observes a safety risk. At the Modern Warrior Defensive Tactics Institute, more than 10,000 officers have been trained in simulated confrontations during the past 15 years. Only one attacker had a significant injury that required medical attention. It is interesting to compare this rate of injury to the findings described in an article by Minor, Rudnick, and Plumstead elsewhere in this issue. The low rate of injury at the Modern Warrior Defensive Tactics Institute can be explained by the use of equipment, selection of the attackers, and use of safety procedures. The training suits are modified to offer the best protection and mobility. The attackers are experienced defensive tactical experts who are trained in simulation confrontations. Their training includes a complex obstacle course, which they have to complete with the training suits. A safety briefing is given before the fight. At least three instructors monitor the fight and the equipment for safety issues. The attackers work in two shifts, allowing one group to rest and hydrate while the other group fights with an officer.


Fig. 2. Simulated fights. Three attackers with protective suits fight with an officer.




Other training

Other dangerous training activities include high-speed driving and the use of explosives and distraction devices. Some agencies use helmets during driving exercises. Distraction devices, or flash-bangs, create a loud noise and a bright light when they explode. They are used by tactical teams. Several officers experienced severe upper-extremity injuries when distraction devices exploded while still held by the officers. When deploying distraction devices or explosive charges, the entire procedure should be supervised step by step by a safety officer. Typically, the trainee announces loudly each step to make sure that none is missed. Officers should wear flame-resistant gloves that are made of leather and Nomex (DuPont, Wilmington, DE). Flame-resistant Nomex uniforms also could be used. Medical kits and fire extinguishers should be readily available during driving, explosive-, and distraction-device training.

Accidental shootings

Between 1992 and 2001, 29 officers died from accidental shootings in the United States [1]. Nine officers died from accidental shootings during training, 18 officers died in  crossfires, mistaken for subject, and firearm mishaps,  and two officers died in unknown circumstances. Mistaken-identity shootings happen when off-duty or plainclothes officers draw their firearms without obvious police identification. Other officers perceive them as suspect with a gun and might shoot if they seem to be a threat. Several procedures can be implemented to decrease the risk for mistaken-identity shootings. Some police departments issue bright orange armbands with police markings for plainclothes officers to be identified when necessary. Clothing with several concealable pull-down police identification flaps is available. An appropriate procedure for plainclothes officers is to hold their badge or identification above the head and turn it back and forth and to state who they are. This approach is helpful when holding a suspect at gunpoint to prevent mistaken-identity shootings when responding uniformed officers, possibly from a different agency, arrive on the scene.

Home firearm safety is a critical issue for law enforcement officers who have families, especially for officers with young children. Each year, children of law enforcement officers are killed or wounded with the firearms of their parents. Children as young as 2 years old can shoot and kill themselves with a handgun [6], and a 3-year-old was able to pick up a pistol and shoot and kill his father, a police officer [7] . Every law enforcement agency should teach home firearm safety programs to its officers. If the firearms are not directly under the control of the officer or a trusted adult, they should be secured in a locked safe and not just hidden [8] . The ammunition could be locked in a separate location. Weapons that are not used for a long time may be disassembled partially. Officers may want to keep a loaded gun available for personal and home defense while at home. A quick access safe, with only four or five buttons, is a recommended method of keeping the home defense gun. The officer, however, should be in the area immediately surrounding this type of safe, as children might open it given enough time. Children also should be educated about firearm safety. The Eddie Eagle GunSafe Program of the National Rifle Association teaches the following steps if a child finds a gun: stop, don't touch, leave the area, and tell an adult [9] . Officers should talk to their children about firearm safety in a way that is appropriate for their age. Children could have access to the unloaded firearm under the direct supervision of the officer or a trusted adult to decrease their curiosity and demystify guns.
Police weapons [Return to Article Outline]

Each issued weapon raises several concerns, including safety for the public, safety for the officer, effectiveness, and training. Nonlethal weapons have to be assessed for the injuries that they could cause to suspects.

The design of firearms tends to be universal, but modifications are sometimes necessary for specific classes of users. Law enforcement organizations use handguns and long guns (shotguns, carbines, rifles, submachine guns). Excessive recoil should be avoided by selecting proper calibers and ammunition. Some agencies are replacing shotguns with carbines, because officers complained of the recoil created by the shotgun. Although shooting technique and ammunition could mitigate perceived recoil, officers usually perceive carbines as being more user friendly. Female and small-sized officers may need different handguns with smaller grips and shorter trigger reach [10] . Grip-strengthening exercises seem to help the shooting abilities of female and small-sized officers (P.J. Messina, personal communication, 2003). The stocks of most shotguns and rifles are too long for police work and need to be shortened, even for average-sized men (J.S. Farnam, personal communication, 2003). Night sights are self-luminous tritium inserts that are imbedded in the regular sights of a firearm. One study found that night sights improved shooting accuracy in low-light conditions [11]. Night sights are recommended for handguns and long guns.

Nonlethal weapons include pepper spray, batons, TASER (Thomas A. Swift's electric rifle), and nonlethal rounds (Fig. 3) . Pepper spray and other chemical agents are discussed more fully in an article by Czarnecki elsewhere in this issue. The TASER is an electrical immobilization device that shoots probes into a suspect. Different models and brands exist. The probes stay connected to the weapon by a high-voltage insulated wire, which transmits electrical pulses to the suspect. The Advanced TASER M26 (TASER International, Scottsdale, AZ) is probably the most common TASER unit used by law enforcement. Although TASERs are not a solution for each violent situation, a sheriff's office found that, since the TASER was issued 3 years ago, injuries to deputies during arrest situations have dropped by 88% [12].


Fig. 3. Nonlethal weapons. From top to bottom: telescopic side-handle baton, pepper spray, telescopic Autolock baton with Hindi Baton Cap.


Police officers have used impact weapons for centuries. Modern batons are lighter, more effective, and more practical than earlier versions. Most police departments issue telescopic batons. Lengths typically range from 16 to 31 inches when expanded, and from 6 to 13 inches when collapsed, depending on the model. Batons are made of polycarbonate, resin composites, wood, plastic, or steel. The side-handle baton, inspired by the martial art weapon tonfa, allows more control and blocking techniques. A telescopic side-handle baton is available. One of the best innovations in baton ergonomics is the Autolock baton with a Hindi Baton Cap (Monadnock Lifetime Products, Fitzwilliam, NH). Most telescopic batons require a hard impact on the tip to collapse. The Autolock closes when a button is pushed, making it less likely to close accidentally during a fight. The Autolock can be fitted with a weighted, large urethane tip that increases the impact force and decreases the risk for lacerations to the suspect. The Hindi Baton Cap is a half-sphere that can be added to the grip extremity of the baton. The cap helps the officer to retain and control the baton and makes some striking techniques more effective (see Fig. 3).

Safety and protective equipment

Medical kits

Officers should have access to a medical kit at all time. They should receive enough first aid training to be able to use issued medical kits and to protect themselves against blood-borne pathogen exposures. Advanced emergency medical training is desirable. In some agencies, every officer is a certified EMT. More and more agencies issue automated external defibrillator to regular patrol officers. Officers should obtain training in tactical medicine (eg, how to treat penetrating trauma on themselves or their partners) while operating in an unstable tactical environment.

Officers should carry a tourniquet at all times and be trained in its use. Tourniquets are safe if used properly, especially if left on an extremity for less than 1 hour [13,14] . They are effective and easily placed in less than 30 seconds. Once placed, both hands of the wounded officer are free to continue the fight. In military special operations, it is recommended that the only medical intervention while under fire should be to stop any life-threatening external hemorrhage with a tourniquet. It is recommended that military special operation forces carry a readily available tourniquet at a standard location on their uniforms. Tourniquets alone could save 60% of all the preventable deaths from combat trauma [14].

A personal medical kit, carried by each officer, could include one tourniquet, two trauma dressings, two rolls of conforming gauze, and one pair of latex or nitrile gloves. A more comprehensive medical kit should be carried in the police car. In special circumstances, such as a search warrant or tactical operation, a large medical kit should be available. Additional items, depending on the level of medical training of the officers, may include: advanced life support supplies and medications; additional tourniquets, trauma dressings, and rolls of conforming gauze; dressing materials, including nonadherent dressings, tape, bandage strips, cohesive bandage, elastic wraps, adhesive bandages, gauze pads, and safety pins; pocket mask; oropharyngeal and nasopharyngeal airways; splints; space blanket; EMT shears; cold compresses; acetaminophen; ibuprofen; aspirin; antibiotic ointment; saline drops; antiseptic solution; alcohol gel.

Infection control

Infection control involves the use of gloves and eye protection. A spitting mask is a mesh bag that is placed around the head of a suspect to prevent the biting of or spitting at the officer. Alcohol-based gel can be used when water and soap are not available. It is recommended to carry alcohol-based gel in every police car. Bio-Safe Antibacterial Skin Protectant (Bio-Safe Enterprises, Milwaukie, OR) acts like a liquid glove. It is applied on the skin and dries, creating a bactericidal barrier for several hours.

Ballistic vests

Soft ballistic vests (or body armor) have been available to law enforcement officers since 1973. Modern body armor is more comfortable, lighter and more flexible than ever. It is made with synthetic fibers: Kevlar (DuPont, Wilmington, DE), Spectra (Honeywell, Morristown, NJ), or Zyloflex (Toyobo Co., Ltd., Osaka, Japan). More than 2500 officers have been saved from serious injury or death by ballistic vests [15].

The National Institute of Justice (NIJ) standard 0101.04 rates soft body armor in three main categories: IIA, II, and IIIA (from weakest to strongest protection) [16] . Level IIA armor protects against 9-mm full metal jacketed round nose bullets, with nominal masses of 8.0 g (124 gr [grains]) impacting at a minimum velocity of 332 m/s, and against 40 S&W caliber full metal jacketed bullets, with nominal masses of 11.7 g (180 gr) impacting at a minimum velocity of 312 m/s. Level II armor protects against 9-mm full metal jacketed round nose bullets, with nominal masses of 8.0 g impacting at a minimum velocity of 358 m/s, and against 357 magnum jacketed soft point bullets, with nominal masses of 10.2 g (158 gr) impacting at a minimum velocity of 427 m/s. Level IIIA armor protects against 9-mm full metal jacketed round nose bullets, with nominal masses of 8.0 g impacting at a minimum velocity of 427 m/s, and against 44 magnum jacketed hollow point bullets, with nominal masses of 15.6 g (240 gr) impacting at a minimum velocity of 427 m/s. Level III and level IV are rigid body armors that protect against rifle rounds.

Level II armor should be suitable for most police officers. Level IIIA armor should be issued to officers who are involved in high-risk operations, such as warrant service, hostage rescue, and protective details. Ballistic vests can be improved by fitting a trauma plate (usually 8x5 inches) on the chest. Trauma plates can be soft and made of the same material as the ballistic vest, or rigid and made of ceramic or metal. Trauma plates offer level IIIA, III, or IV protection.

It seems that no type of body armor has failed in the streets. Most ballistic vests consistently stop handgun rounds beyond their ratings. Between 1992 and 2001, 19 officers died from gunshots that penetrated their body armor. They incidents involved rifle rounds. An officer who is shot while wearing a ballistic vest is likely to experience benign blunt trauma to the chest. There is no reported case of death from blunt trauma caused by handgun rounds. A death from traumatic aortic dissection was reported when an officer was shot with a rifle while wearing soft body armor. It is recommended that officers go to an emergency department as soon as possible if they are shot while wearing a ballistic vest. A chest x-ray should be performed, because pulmonary contusion has been reported (C.J. Holliman, MD, personal communication, 1999).

Ballistic vests have been known to fail during tests. It is recommended that police departments conduct their own tests on new vests and on vests that randomly are taken from officers in the field. Improper storage (creating folds), high temperature, and corrosive chemicals could decrease ballistic capabilities. The exact lifespan of ballistic vests is unknown, but some manufacturers recommend changing vests every 5 years.

Puncture-resistant vests are available with or without ballistic protection. They are recommended for correction officers, who are more likely to be assaulted with improvised knives or picks rather than firearms. Puncture-resistant vests are regulated by the NIJ standard 0115.00 Stab Resistance of Personal Body Armor.


Police officers wear gloves for different reasons. Latex gloves protect against bodily fluids. Compared with latex gloves, nitrile gloves are more resistant to puncture and chemicals and are less allergenic. Powdered latex gloves should be avoided. Leather gloves are used for general hand protection and can be lined with Kevlar or Spectra for increased resistant against cuts. Many tactical operators prefer flame-resistant flight gloves, which issued by the US Air Force, with thin leather palms, Nomex backs, and long cuffs. Gloves can be worn for protection against the cold. If gloves are worn routinely, officers should shoot with and without the gloves during firearms training.


Officers can wear prescription eyeglasses and sunglasses. OSHA mandates eye protection when the eyes are exposed to flying particles or caustic liquids [14] . It is recommended that officers wear safety eyeglasses that comply with the ANSI Z87.1-1989 standard during high-risk operations, such as warrant service and tactical operations. Prescription eyeglasses and sunglasses worn on patrol should be as safe as possible and have unbreakable lenses. Another article by Good and Taravella in this issue offers a detailed discussion of vision issues in law enforcement.

Helmets and shields

Helmets are issued for ballistic protection, riot control, and special vehicle operation (motorcycles, bicycles, snowmobiles). The NIJ standard 0104.02 establishes rules for riot helmets and face shields, defining peripheral vision, impact attenuation, penetration resistance, and retention system. Ballistic helmets are used during tactical operations. Ballistic shields are used during warrant service and tactical operations and can be issued to patrol officers. Shields require special training. The NIJ standard 0108.01 regulates ballistic-resistant protective materials, including helmets and shields. A level IIIA material, probably the most common, stops a 44 magnum round fired from a pistol and a 9-mm round fired from a submachine, at given velocities.

Other equipment

The remaining equipment of police officers includes uniform, headgear, boots, or shoes, duty belt, duty belt accessories, and radio. Duty belt equipment typically includes handgun, handcuffs, flashlight, latex gloves, baton, radio, and pepper spray canister (Figs. 4 and 5) . Holsters contain one of several retention devices to prevent criminals from taking the gun from the officer. Between 1992 and 2001, 594 officers were slain with firearms, and 46 (7.7%) were killed with their own weapon [1] . In the 1970s and early 1980s, about 20% to 25% of officers who were slain with firearms were killed with their own weapons. Better-designed holsters and firearm retention training have helped to decrease the number of officers who are killed with their own weapons. Some modern rigid plastic holsters may not allow the drawing of the firearm from unusual body positions (eg, while on the ground). New holsters should be tested to make sure that officers can draw from any position, including with the nondominant hand. Holsters designed for men may not fit female officers because of difference in hip size. Duty belts and holsters are discussed more fully in the last part of this article.

Fig. 4. Duty belt for tactical officer. Thigh holster and thigh magazine pouch are shown.






Fig. 5. Thigh holster for tactical officer.



Duty belts can be heavy and uncomfortable when fully loaded. Alternatives to duty belts include suspenders and tactical vests. These alternatives distribute the weight of the equipment over the shoulders and the chest rather than just on the waist. Military Y and H suspenders can be used to support a load-bearing belt. A tactical vest contains multiple pouches over the chest and back. Some agencies refuse to allow suspenders and tactical vests to be worn because of their military appearance.

Officers should avoid placing hard objects (typically handcuffs) on the lumbar spine. In case of a fall, the spine could be injured severely by the handcuffs or similar objects. They also could create back pain from constant pressure on the lower back while sitting in a car. It is recommended that a soft pouch (eg, containing latex gloves) be placed over the lumbar spine.

Uniforms can be made of cotton, synthetic fabrics, wool, and blends. The material is chosen according to the weather and the assignment. Cotton uniforms are preferred in a warm environment. Synthetic fibers and blends are more durable than are pure natural fibers. Flame-resistant Nomex uniforms are useful for tactical teams, aviation units, and other specialized assignments. Officers should not wear regular neckties, which could be used to choke them. Breakaway and clip-on ties are common among uniformed officers. Plainclothes officers could have a tailor turn a regular tie into a breakaway tie using Velcro fasteners (Velcro USA, Manchester, NH).

Officers should make sure that their equipment does not get loose during intense physical activity or caught by protruding objects in the environment. Microphones have been known to come off during foot pursuits, creating a potential tripping hazard. Microphones could be attached to the uniform with a Velcro strap.

Flashlights are used to search an area and to identify suspects. Officers should carry flashlights even during daytime because of the possibility of searching buildings without other lighting. It is recommended for officers to carry two flashlights. Modern police flashlights are compact (3  8 inches long), light (2 -11 ounces), and powerful (6000-15,000 CP). Thinner and smaller lights are easier to control and are more likely to be carried at all times. Officers should be trained to use the flashlight in a tactical manner and to deploy it in conjunction with the firearm. Metal flashlights can be uncomfortable when left under direct sunlight or held in an ungloved hand on a cold day. Because lights often are placed on uneven surfaces (eg, automobile trunk or hoods) while officers are searching suspects, flashlights with an antiroll capability should be considered. Round flashlights are more likely to roll compared with flashlights with a polygonal bezel.

Most officers carry a knife. The knife can be used as a rescue tool (eg, to cut seatbelts) and as a general utility knife. In an emergency, it could be used as a defense tool. It is desirable for officers to obtain defensive knife training. When carried by the officer, the knife should be concealed from the general public as much as possible. If it is a folding knife, which most officers carry, it should offer a smooth one-handed ambidextrous opening with a locking mechanism. Blades should be kept sharp.
Duty belt study [Return to Article Outline]

The problem of the duty belt discomfort is a significant health and safety issue for uniformed personnel. It is characterized by low back or anterior hip pain, sometimes with paresthesias in the distribution of the lateral femoral cutaneous nerve. The pain and paresthesias are caused by pressure on the hip, pelvis, and low back areas of uniformed personnel, which is exerted by the edges of the duty belt, holster shank, and other equipment attached to the belt and by the grip or barrel of the weapon, especially when seated in patrol vehicles. Duty belt discomfort seems to be more common in female and in slender or short male officers. Pain and numbness may lead to the frequent changing of the holster position and can result in a decrease in officer safety because of inconsistent weapon location and awkward postures when drawing the weapon.


Duty belt discomfort has been worsening in recent years for several reasons, including the increase in time officers spend in vehicles and the heavier gear carried on the duty belt. The conversion from revolvers to semiautomatic weapons and the associated increased weight of the spare magazines on the belt has added 3 to 4 pounds in many jurisdictions. Additional carried items include radios and extra handcuffs in some jurisdictions. There has been a trend toward designing less flexible duty belt holster systems to increase an officer's weapon retention in the event of physical encounter with a suspect. The more rigid the duty belt  holster system is, the more critical are its shape and location in obtaining a proper fit for an individual. Because breaking in a system can take several years, the rigidity of newly issued belt  holster systems is a major problem. This issue affects cadets, other individuals entering law enforcement, and all members of a force when a change in weaponry is underway.

The shape of seats in patrol cars has shifted toward wrap-around designs with bolsters on the sides. These seats produce pressure on the weapon and radio and tend to push the officer forward, depriving him or her of low back support. Short officers often find that the barrel of the gun presses downward into the car seat, resulting in an upward pressure of the belt or the grip of the weapon against the rib cage or body armor. Worn vehicle cushions tend to exacerbate this problem by allowing the officer to sink lower into the middle of the seat. These factors are mediated by the

  • Shape and location of the belt buckle, holster, loop, and shank;

  • Vertical location of the holster relative to the officer's pelvis and hips;

  • Vertical orientation or cant of the weapon; and

  • Seat design, adjustment, and condition of seats in the police car

In 1997, the California Highway Patrol (CHP) asked the University of California San Francisco/Berkeley Ergonomics Program to conduct a study of alternative holster and duty belt designs. Over a 4-month period (August 28 to December 31, 1997), 36 CHP uniformed personnel participated in this study, nine of whom were controls with no history of duty belt-related symptoms. Once a month, uniformed personnel were fitted with alternative holsters or belts, but were allowed to reject any belt or holster that they found to be painful or uncomfortable. Participants were given the choice of several seat and lumbar cushions to be used in police cars. The subjects were required to complete a checklist to record the type of work and vehicle they were using and to rate their hip, leg, and back discomfort every 10 days.


Belt characteristics

The belt that overwhelmingly was preferred by study participants had the following characteristics:

* Rounded, padded edges on the top and bottom
* Lower profile, with a 2-inch thickness (top to bottom) of belt and buckle
* Washable, moderately flexible nylon material
* Hook-and-loop interface between inner and outer belts

Traditional leather belts with buckle closures are less adjustable than are newer designs, making good fit difficult. The adjustment holes for the buckle are usually 1.125 inches apart, often leaving the belt too tight or too loose. A belt that is too loose presents safety problems in the event of a foot pursuit or an encounter with a suspect. A belt that is too tight exerts increased pressure on the officer's pelvic and hip areas. A belt with hook-and-loop closures allows the length to be infinitely adjustable to the officer's girth, even if the girth changes during the course of a day. Duty belts commonly have reinforcing strips of additional leather, semi-rigid polymer, or other stiff materials that can conform poorly to the shape of the human body. The hard edge of the belt tends to dig in under the ribs and in the lateral and anterior pelvis. A belt with rounded, padded edges on the top and bottom that conform to the body distributes the load better.

Many standard duty belts are 2.25 inches wide. This study indicated that replacing traditional belts with nylon belts that are 2 inches wide resulted in increased officer comfort with fewer problems with the edges of the belt digging in under the ribs and on the rim of the pelvis. Leather duty belts, with leather magazine and accessory cases, are approximately 1.3 pounds heavier than equivalent synthetic belts. The use of keepers to attach inner belts to outer belts is a problem for some uniformed personnel, especially officers with narrow waists. The space available for weapon, radio, and other accessories may be so limited that there is not enough room for keepers on the belt. A relatively thin inner duty belt with a hook-and-loop surface that interfaces with the outer belt allows for the elimination of keepers and is more stable when entering and sitting in a vehicle.

Duty belts commonly have a rectangular brass buckle that is 2.0 inches wide nearly 3.0 inches high. This buckle does not have an optimal size and shape for uniformed personnel who are sitting in a vehicle, as it tends to place uncomfortable pressure on the anterior pelvis and abdomen. The belt preferred by study participants has a rounded buckle (2.25 inches high) that is narrower in the middle (1.75 inches high), leading to improved fit when sitting. It has a triple-retention design that, for officer safety, requires all three buttons to be pressed with two hands to release the buckle.

Holster characteristics

The most preferred holster in this study had a swivel cant, allowing it to change to a more horizontal position when the officer was seated in a vehicle. The trend toward designing less flexible duty belt  holster systems has produced holster and shank designs with steel or rigid polymer inserts between layers of leather or nylon. A swivel between the holster and belt allowed the holster to align with the officer's thigh when seated in a vehicle, reducing pressure of the weapon against the seat.

The shape of the shank between the belt and holster is a critical variable in avoiding discomfort of the duty belt. All shanks are curved to some extent in the area of the officer's hip, although their shapes vary widely. Some holsters examined in this study had a vertical steel reinforcing ridge that protruded toward the user, exerting pressure on sensitive anatomic structures on the front or side of the hip.

Holster designs can be divided into the following three categories:

1. High-ride design: The butt of the weapon is above the duty belt.
2. Mid-ride design: The butt of the weapon is about the same level as the duty belt.
3. Low-ride design: The butt of the weapon is largely below the duty belt.

This study confirmed that vertical location was an important factor. Choice of holster height, by being able to modify an existing holster (some manufacturers offer spacers for their holsters) or by being able to choose a holster that hangs at the right height, is critical.

A holster that holds the weapon with the barrel in a vertical orientation is most likely to create pressure on the ribs or body armor at the grip and on the seat of a vehicle at the barrel end. In general, the most-preferred holsters had more cant. Swivel holsters, in which the barrel position can be changed so that it is more horizontal (ie, in line with the thigh) when seated, offer a form of adjustable cant.

Police car seats

The backrests of contoured, bucket seats tend to press against the weapon and radio when an officer is seated. This position deprives the officer of adequate lumbar support. The seats in the police cars in this study have a mild lumbar curve and a peak located 6 inches above the seat cushion. Depending on the officer's size and shape, there were significant mismatches between the backrest and the shape of the seated officer's spine.

In seats with adequate pelvic support from the seat cushion, only a lumbar support was needed to fill the space between the seat and the participant's back. If the lumbar support was narrow enough (usually 12 inches from right to left), clearance for the weapon and the radio was possible, and it reduced pressure on the officer's hip and trunk areas. In older vehicles, however, this situation did not occur. As a vehicle ages, the foam in the seat loses its loft. With worn seats, it is nearly impossible to keep the back well supported if there is not some supplemental support under the pelvis.

The authors conducted a systematic evaluation of the interaction of the duty belt and holster designs with seat cushions that could be added to police cars. Two thirds of the participants in this study requested supplementary back or seat cushions for use in their cars. The most frequently requested items were:

  • A seat cushion with upholstered memory foam and a rubber layer underneath to decrease the tendency to slide as the officer enters or exits the vehicle

  • A contoured, upholstered lumbar cushion with a plastic insert to maintain its shape and straps to hold it in place around the backrest

  • A combination back and seat cushion with hinged back and seat sections. The backrest portion was shaped to the preference of the user and supplemented by an optional upholstered lumbar pad.


  1. On average among all of the participants in the study, there was a significant reduction in the frequency and severity of pain for participants who began the study with duty belt discomfort.

  2. Among the symptomatic group, approximately two thirds of the men and one quarter of the women became pain-free by the end of the study. No instances of increased discomfort or pain occurred.

  3. All participants, including those in the control group, chose a nylon belt instead of the standard leather belt. Participants chose a variety of holsters, usually one with a swivel at the shank.
    About two thirds of the participants chose seat or lumbar cushions for patrol cars.


Dr. Fabrice Czarnecki thanks Thomas J. Aveni, Massad F. Ayoob, Michael DeBethencourt, Jennifer Haas, John Holschen, Lt. Adam Kasanof, Elizabeth A. Kennedy, James W. Lindell, Edward F. Mandelbaum, Phillip J. Messina, and the members of the American Society for Law Enforcement Training for their assistance with this project.


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a The Gables Group, Inc., 1172 South Dixie Highway, Coral Gables, FL 33146, USA
b Family Health Center, Franklin Square Hospital Center, 9101 Franklin Square Drive, Suite 205, Baltimore, MD 21237, USA
c Senior Ergonomics Consultant, Berkeley Ergonomics Program, University of California San Francisco, 1301 South 46th Street, Building 163, Richmond, CA 94804, USA 


* Corresponding author. Family Health Center, Franklin Square Hospital Center, 9101 Franklin Square Drive, Suite 205, Baltimore, MD 21237, USA

doi: 10.1016/s1526-0046(03)00100-6


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