1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationPD CEN/TR 16148:2011Head and neck impact, burnand noise injury criteria A Guide for CEN helmetstandards committeesPD CEN/TR 16148:2011 PUBLISHED DOCUMENTNational forewordThis Pub
2、lished Document is the UK implementation of CEN/TR 16148:2011.The UK participation in its preparation was entrusted to T e c h n i c a l C o m m i t t e e P H / 6 , H e a d p r o t e c t i o n .A list of organizations represented on this committee can be obtained on request to its secretary.This pub
3、lication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. BSI 2011 ISBN 978 0 580 71865 6 ICS 13.340.20 Compliance with a British Standard cannot confer immunity from legal obligations.This Published Document was published und
4、er the authority of the Standards Policy and Strategy Committee on 30 June 2011.Amendments issued since publicationDate T e x t a f f e c t e dPD CEN/TR 16148:2011TECHNICAL REPORT RAPPORT TECHNIQUE TECHNISCHER BERICHT CEN/TR 16148 March 2011 ICS 13.340.20 English Version Head and neck impact, burn a
5、nd noise injury criteria - A Guide for CEN helmet standards committees Critres relatifs au traumatisme cervico-facial et aux lsionsdues aux brlures et au bruit - Guide destin aux comits des normes sur les casques de protection du CEN Kriterien fr Verletzungen durch Einwirkung auf Kopf und Hals, Verb
6、rennungen und Lrmverletzungen - Leitfaden fr Arbeitsgruppen, die europische Helmnormen erarbeiten This Technical Report was approved by CEN on 27 December 2010. It has been drawn up by the Technical Committee CEN/TC 158. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cr
7、oatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDAR
8、DIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2011 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. CEN/TR 16148:2011: EPD CEN/TR 16148:2011CEN/TR 16148:2011
9、 (E) 2 Contents Page Foreword 3Introduction .41 Abbreviated injury scale, AIS .52 Peak linear acceleration (A.3.1 b) upper exposure action values: LEX.8heq, = 85dB(A) and Ppeak= 140 Pa; c) lower exposure action values: LEX.8heq, = 80dB(A) and Ppeak= 112 Pa. Table 9 gives values for maximum exposure
10、times as recommended by the UK Royal Aerospace Establishment. Table 9 Maximum exposure time for different noise levels Noise level dB(A) Maximum continuous exposure period (hours)95 3 96 2 99 1 103 0,33 109 0,08 (5 min) 113 0,033 (2 min) 140 0 8 Heat: burns and fatigue (A.6) 8.1 Burns This section w
11、as included for the benefit of those defining Standards for firefighting equipment although it may be used for other applications. Studies have recommended that the range of environment in which firefighters operate is categorised by three levels as follows: Level 1: Routine conditions - air tempera
12、tures up to approximately 100 C and a radiant heat source of up to approximately 1,25 kW/m2. PD CEN/TR 16148:2011CEN/TR 16148:2011 (E) 13 Level 2: Hazardous conditions - air temperatures up to approximately 250 C and a radiant heat source of up to approximately 8 kW/m2. Level 3: Emergency conditions
13、 - air temperatures up to and above 800 C and radiant heat sources from 80 kW/m2up. Table 10 gives the burn injury degree for a range of temperature and exposure time for air and surface contact, and water. The table is compiled from a range of sources with full details in A.6.4. Table 11 gives the
14、burn injury degree for thermal energy and time, and radiation. Table 10 Burn injury degree for a range of temperature and exposure time for air and surface contact, and water Temp.C Time s second m - minute Contact substance Air or surface contact Water Burn injury degree Burn injury degree1st 2nd 3
15、rd 1st 2nd 3rd100 15 s X X 82 30 s X X71 60 s X X 68 1 s NK X 64 2 s NK X 60 5 s X1 X56 15 s NK X 53 1 m NK X 51 3 m NK X 49 5 m X X38 NS safe safe 0 NS X NS = not specified; NK = not known; 1= time not specified for air/surface contact Table 11 Burn injury degree for thermal energy and time, and ra
16、diation Thermal Energy/unit area cal/cm2 (kJ/m2) (average for a range of subjects) Time sec Radiation kW/m2 (average for a range of subjects) Injury3,2 (7,6 ) 0,5 3,8 1st Degree burn 3,13 (7,5 ) 0,5 4,0 2nd Degree burn 4,15 (9,9) 0,5 4,5 3rd Degree burn 8.2 Heat fatigue Equipment to protect from hea
17、t may be available but the greater the temperature against which it is designed to protect the more of an encumbrance it becomes and the greater the fatigue when it is worn. This dichotomy PD CEN/TR 16148:2011CEN/TR 16148:2011 (E) 14 needs to be considered when writing Standards for such equipment,
18、for firefighters, for example, and the following information is presented to help with this. Table 12 Maximum exposure for unimpaired mental performance Temp. (C) Max. exposure for unimpaired mental performance.min. (hr) 40 2334 60 (1)32 120 (2)31 180 (3)30 Not limited The information given in Table
19、 12 is taken from graph given in A.6.5. It is intended as a guide for health and safety at work but is given here to assist with the specification of protective equipment. The graph appears to be exponential hence, the rapid decrease in the maximum exposure for a given temperature increment. 9 Refer
20、ences The Abreviated Injury Scale (AIS). 1990 Revision; Association for the Advancement of Automotive Medecine (AAAM), 2340 Des Plaines River Road Suite 106, Des Plaines, Illinois 60018, USA Allsop, D. L. et. al. (1991). Force deflection and fracture characteristics of the tempero-parietal region of
21、 the human head. 35th STAPP Car Crash Conference, p251 Newman, J A (1980). Head injury criteria in automotive crash testing. 24th STAPP Car Crash Conference SAE J885 (1986). Human tolerance to impact conditions as related to motor vehicle design. US: Society of Automotive Engineers Hobbs, C.A. et al
22、 (1999). European New Car Assessment Programme (Euro NCAP). Assessment Protocol and Biomechanical Limits (Version 2) Yamada, Hiroshi (1970). Strength of Biological Materials. Published by The Williams and Wilkins Company, Baltimore, Maryland 21202 U.S.A. S.B.N 683 - 09323 - 1 PD CEN/TR 16148:2011CEN
23、/TR 16148:2011 (E) 15 Annex A Biomechanics of head injury from impact, noise and heat A.1 General In accidents, the human head is exposed to loads greatly exceeding the capacity of its natural protection. This explains why, despite the extensive research on head injury during the past 50 years and t
24、he continuous improvement of head protection devices, head injury is still by far the most common cause of fatal injury in accidents. The consequences of severe head injuries are often fatal or long lasting and not fully recoverable. Head injuries can be divided into two categories: primary injuries
25、, which are a direct consequence of the physical loading of the head and appear at the time of the accident and secondary injuries, which are directly related to the severity of the primary injuries and can appear up to several days after the accident. Primary injuries can result in several physiolo
26、gical changes, such as necrosis, post-traumatic oedema, increased intracranial pressure, hypoxia, ischemia, intracranial hypertension or other vascular changes. Secondary injuries are directly related to primary injuries, therefore, decreasing the severity of the primary injuries will automatically
27、decrease the severity of the subsequent secondary injuries. A clear understanding of the types of head injury occurring in various types of accident and the injury mechanisms causing these injuries is important to improvements in protective devices. Extensive medical research has led to substantial
28、information on the characteristics of head injuries, the locations in the head and the likelihood of occurrence in the various types of accidents. The characteristics of the most common head injuries occurring in accidents is indicated in Clause 3. Mechanisms causing head injury are still not clearl
29、y understood. Traditionally, head injuries have been related to impacts and accelerations of the head and research has concentrated upon the effects of these two types of loading. Originally, impact and acceleration were studied for their ability to cause only a few particular head injuries. However
30、, in most accidents, impact and acceleration are inseparable and a wide range of head injuries occurs. It is shown in this report that the resulting kinematics of the head and the behaviour of the brain inside the head, rather than accelerations, should be considered as the causes of head injury. Ne
31、vertheless, it is acceleration that is usually measured in helmet impact tests. Thus, the committee members responsible for establishing the requirements for Standards need to be aware of the relationship between acceleration and the implied kinematics of the brain and skull and, in turn, the potent
32、ial for injury. Although the causes of head injury are not fully understood, various head injury criteria have been proposed through the years and some of these criteria (Head Injury Criterion, HIC; Gadd Severity Index, GSI) are used in Standards for head protective devices. Such criteria are review
33、ed and discussed. Premature deafness because of high noise levels can also be classed as an injury. This and the and the converse problem of over attenuation of auditory warnings was also considered. Suggested levels have been included with details of test methods. A section on burn injuries and fat
34、igue related to heat exposure has also been included to assist with writing Standards for equipment to protect firefighters. The skin structure and the category and consequence of burn injuries is described and discussed as is the exposure related to temperature, time and radiation to cause a burn o
35、f a given degree. PD CEN/TR 16148:2011CEN/TR 16148:2011 (E) 16 A.2 Head injuries A.2.1 Head Anatomy The term head injury comprises various kinds of trauma to the skull and its contents. Often, several different types of head injury occur simultaneously in an accident. The anatomical location of the
36、lesions and their severity determine the physiological consequences. In this section, a review of the information found in the literature on the most commonly reported head injuries in accidents is given. The injuries are divided into cranial injuries, skull fractures, and intracranial injuries. The
37、 intracranial injuries are further subdivided into injuries to vascular and neurological tissues. This review is intended to provide the reader with sufficient information on the characteristics of these injuries, their common locations of occurrence in the head, and their relative importance in ter
38、ms of severity of outcome and frequency of occurrence. This will give the reader the required background information for the discussion of the injury mechanisms in Clause 3. Figure A.1 shows the main anatomical structures of the head and their locations inside the head. PD CEN/TR 16148:2011CEN/TR 16
39、148:2011 (E) 17 Key 1 Arachnoid villus 2 Superior cerebral vein 3 Subarachnoid space of brain 4 Cerebrum 5 Superior sagittal sinus 6 Posterior commissure 7 Intermediate mass 8 Corpus callosum 9 Choroid plexus of lateral ventricle 10 Lateral ventricle 11 Interventricular foramen 12 Great cerebral vei
40、n 13 Anterior commissure 14 Cerebellum 15 Pons 16 Pia mater 17 Arachnoid 18 Dura mater 19 Cranial meninges 20 Third ventricle 21 Choroid plexus of third ventricle 22 Straight sinus 23 Medulla oblongata 24 Lateral aperture (of Luschka) 25 Cerebral aqueduct 26 Choroid plexus of fourth ventricle 27 Spi
41、nal cord 28 Fourth ventricle 29 Median aperture (of Magendie) 30 Pia mater 31 Arachnoid 32 Dura mater 33 Spinal meninges 34 Central canal 35 Subarachnoid space of spinal cord 36 Filum terminale Figure A.1 Main anatomical structures of the head and the locations inside the head PD CEN/TR 16148:2011CE
42、N/TR 16148:2011 (E) 18 A.2.2 Skull Fracture Skull fracture can occur with or without brain damage, but is in itself not necessarily an important cause of neurological injury (Gennarelli 1985; Prasad et al. 1985). Skull fracture can be either open or closed. A closed fracture is a break in the bone,
43、but with no break in the overlying skin. An open fracture, on the other hand, is a contiguous break in both the skin and underlying bone and is more serious than a closed fracture because of the accompanying risk for infections. Usually, skull fractures are subdivided according to their location of
44、occurrence. A distinction is thus made between fractures in the face, in the vault of the skull and in the base of the skull. Even though fractures to the face are very painful and inconvenient for the patient, they do not constitute a threat to life nor cause serious neurological damage. Fractures
45、to the vault can cause meningeal and cortical injury when fragments of fractured bone enter the cranial cavity. However, the most threatening form of skull fracture is a basilar or basal skull fracture. This part of the skull contains passages for the blood vessels, providing the blood supply to the
46、 entire brain, and to passages for the neurological connections between the brain and the rest of the body. Fractures of the skull base around the cavities where the blood vessels and nerves pass can lead to damage to these vital connections. Within the above-mentioned anatomical areas of the skull,
47、 skull fractures are usually further subdivided into linear, depressed and comminuted fractures (Thomas et al. 1973). In a linear skull fracture, skull penetration does not occur and the contact effects are confined to the contact area. The skull is only cracked in linear skull fractures. Usually, t
48、he crack has the form of a single line running from the area of impact and may involve either the inner or outer table or both (Douglass et al. 1968). A variant of the linear fracture is the stellate fracture, which is a group of star shaped cracks radiating from the central impact point. The dural
49、arteries lie close to the inner skull table and are, therefore, sensitive to skull deformation. Linear fractures perpendicular to the path of a dural artery may rupture the artery and cause an extradural haematoma (see section Intracranial Haematoma), which can compress the underlying brain (Douglass et al. 1968). Thomas et al. (1973) stated that approximately 80 % of skull fractures are linear. According to Bakay and Glasauer (1980), about 50 % of the linear fractures occur in the mid portion of the skull and extend toward the
