PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Head Protective Devices”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
PubMed1997

The effects of padded surfaces on the risk for cervical spine injury.

STUDY DESIGN: This is an in vitro study comparing cervical spine injuries produced in rigid head impacts and in padded head impacts. OBJECTIVES: To test the hypothesis that deformable impact surfaces pose a greater risk for cervical spine injury than rigid surfaces using a cadaver-based model that includes the effects of the head and torso masses. SUMMARY OF BACKGROUND DATA: It is widely assumed that energy-absorbing devices that protect the head from injury also reduce the risk for neck injury. However, this has not been demonstrated in any experimental or epidemiologic study. On the contrary, some studies have shown that padded surfaces have no effect on neck injury risk, and others have suggested that they can increase risk. METHODS: Experiments were performed on 18 cadaveric cervical spines to test 6 combinations of impact angle and impact surface padding. The impact surface was oriented at -15 degrees (posterior impact), 0 degree (vertex impact), or +15 degrees (anterior impact). The impact surface was either a 3-mm sheet of lubricated Teflon or 5 cm of polyurethane foam. RESULTS: Impacts onto padded surfaces produced significantly larger neck impulses (P = 0.00023) and a significantly greater frequency of cervical spine injuries than rigid impacts (P = 0.0375). The impact angle was also correlated with injury risk (P < 0.00001). CONCLUSIONS: These experiments suggest that highly deformable, padded contact surfaces should be used carefully in environments where there is the risk for cervical spine injury. The results also suggest that the orientation of the head, neck, and torso relative to the impact surface is of equal if not greater importance in neck injury risk.

Adult↗
PubMed1992

A new generation of U.S. Army flight helmets.

Head injuries are the most common cause of fatal injury in helicopter crashes. For over 80 years, the U.S. Army has used crash investigation studies to redesign flight helmets. This paper describes the evolution of the new fielded U.S. Army helmet, the Sound Protection Helmet No. 4B (SPH-4B), and compares its protective features to its predecessors, especially the SPH-4. A major contribution to the helmet design process was made by the Aviation Life Support Equipment Retrieval Program (ALSERP), a functional program at the U.S. Army Aeromedical Research Laboratory (USAARL). ALSERP has analyzed more than 500 helmets involved in crash events since 1972. Based on these studies of critical safety factors, the Army has developed and deployed the SPH-4B, a new helmet with improved energy absorption, retention, and stability.

Craniocerebral Trauma↗
PubMed2000

Acceptability of baseball face guards and reduction of oculofacial injury in receptive youth league players.

GOALS: To assess the relative injury reduction effect and acceptability of face guards on batter's helmets. METHODS: A non-randomized prospective cohort study among 238 youth league baseball teams in Central and Southern Indiana during the 1997 season. Coaches, parents, and players were asked to respond to pre-season and post-season questionnaires. Approximately one half of the teams were supplied with face guard helmets (intervention); all others used this protection at their discretion (comparison). RESULTS: Parents, players, and coaches on the intervention teams reported a reduction in the incidence of oculofacial injuries compared with comparison team respondents (p=0.04). There was no reported adverse effect of face guard use on player performance. CONCLUSIONS: Helmet face guards should be required for batters to prevent facial injuries in baseball.

Attitude to Health↗
PubMed2005

[A new type of active noise cancellation earmuffs].

OBJECTIVE: To develop a new type of feedback active noise cancellation earmuff (ANCE) for aviator's helmet. METHOD: A mathematical model of such a structure was established based on frequency response function and automatic control theory. The method and role for designing ANCE controllers were summarized and the optimum design method was used for designing the controllers. RESULT: The acoustic components and simulation circuit were well matched. One of the prototype can attenuate the noise more than 15 dB in the frequency range of 50-2000 Hz (19 dB at the highest). CONCLUSION: The noise cancellation value of this earmuff has achieved international level and it can be mass-produced.

Aerospace Medicine↗
PubMed1979

Radiation dose to the eyes using a "German helmet" field with the 4-MV linear accelerator.

A "German helmet" field defined by depleted uranium or Asarcola blocks was used to reduce the dose to the lens. With the uranium blocks, the lenticular dose was reduced to about 60% of the central axis dose (CAD). The Asarcola blocks reduced the lenticular dose to about 43% of the CAD. Even further reduction (15% CAD) was achieved by tilting the gantry 5 degrees or 10 degrees.

Eye↗
PubMed1994

Two solutions to the problem of noise exposure for motorcyclists.

Two solutions to the problem of excessive noise exposure and consequent hearing loss in motorcyclists were investigated and are described. One was an antecedent behaviour-modifying 'prompting' strategy, where a set of earplugs and an advice sheet were provided at the point of sale to consecutive purchasers of new motorcycle crash helmets. Forty-eight riders were recruited but data for analysis were only available in 41. The earplug usage rate was significantly increased from 27% to 83% by this intervention. The second solution involves various aerodynamics and sound-proofing helmet modifications made in an effort to reduce interior noise levels. The only modification which achieved a significant reduction from previously reported average sound levels was the incorporation of a pair of 'standard' earmuffs under the helmet shell. This gave noise levels of 84 dB(A) at 22 m/s (50 mph) and 93 dB(A) at 36 m/s (80 mph), compared to known average values of 95 dB(A) and 107 dB(A), respectively. Both solutions are eminently feasible and desirable, and we hope that the motorcycle industry will act on them.

Adult↗
PubMed1987

Measuring helmet sound attenuation characteristics using an acoustic manikin.

The sound attenuation characteristics of two military helmets were measured using an acoustic manikin as the test apparatus. The manikin results are compared to the results of attenuation measurements made on human subjects wearing identical helmets. The testing room and instrumentation were the same for both the manikin and human subjects. Procedures in ANSI S3.19-1974 were used in the real-ear attentuation at threshold (REAT) part of this study. The results are encouraging as they suggest that the manikin may be used in place of a panel of human subjects to evaluate the hearing protection characteristics of military head gear.

Acoustics↗
PubMed1991

Development of a new noise helmet.

A prototype for a new noise helmet was developed because high noise levels were not sufficiently attenuated by commercially available helmets. The new helmet was designed to be tight, especially in the area of the throat and face, and to cover the entire head. The noise attenuation properties of the new helmet were tested against pink noise in an anechoic room, jet engine noise, and low-frequency noise with the test subjects wearing a miniature microphone under the protector. The new helmet provides insertion loss of over 50 dB, which is 18-29 dB more attenuation than that of the tested earmuffs in the frequency range of 1-8 kHz. It is also better (8-13 dB) than the tested earmuffs at frequencies of 125-1000 Hz, and it protects against air impurities because the air fed into the helmet is filtered.

Ear Protective Devices↗
PubMed2002

Mechanisms of snowboarding-related severe head injury: shear strain induced by the opposite-edge phenomenon.

OBJECT: To date, there has been no published study in which the focus was on the mechanisms of head injuries associated with snowboarding. The purpose of this study was to identify these mechanisms. METHODS: The patient population consisted of 38 consecutive patients with snowboarding-related major head injuries who were treated at two hospitals in Japan, where for years many winter sports injuries have been treated. The skill level of the snowboarder, the cause of the accident, the direction of the fall, the site of impact to the head, and the condition of the ski slope were examined. The injuries were classified as coup, contrecoup, or shear injuries. The predominant features of snowboarding-related major head injuries included: falling backward (68% of cases), occipital impact (66% of cases), a gentle or moderate ski slope (76% of cases), and inertial injury (76% of cases [shear injury in 68% and contrecoup injury in 8% of the patients]). Acute subdural hematoma frequently occurred after a patient fell on the slope (p = 0.025), fell backward (p = 0.0014), or received an occipital impact (p = 0.0064). Subcortical hemorrhagic contusions frequently occurred after the patient fell during a jump (p = 0.0488), received a temporal impact (p = 0.0404), or fell on the jump platform (p = 0.0075). Shear injury frequently occurred after a fall that occurred during a jump or after simple falls on the ski slope, and contact injury was frequently seen after a collision (p = 0.0441). CONCLUSIONS: The majority of severe head injuries associated with snowboarding that occur after a simple fall on the slope are believed to involve the opposite-edge phenomenon, which results from a fall backward on a gentle or moderate slope causing occipital impact. The use of a device to protect the occiput is proposed to reduce head injuries associated with snowboarding.

Adolescent↗