Test equipment. (1) ISO headforms without the lower chin portion shall be used.
The retention system strength test equipment shall consist of a dynamic impact apparatus that allows a 4-kg (8.8-lb) drop weight to slide in a guided free fall to impact a rigid stop anvil (see Figure 8 of this part). Two cylindrical rollers that spin freely, with a diameter of 12.5±0.5 mm (0.49 in.±0.02 in.) and a center-to-center distance of 76.0±1 mm (3.0±0.04 in.), shall make up a stirrup that represents the bone structure of the lower jaw. The entire dynamic test apparatus hangs freely on the retention system. The entire mass of the support assembly, including the 4-kg (8.8-lb) drop weight, shall be 11 kg±0.5 kg (24.2 lb±1.1 lb).
Test procedure. (1) Place the helmet on the appropriate size headform on the test device according to the HPI. Fasten the strap of the retention system under the stirrup.
Mark the pre-test position of the retention system, with the entire dynamic test apparatus hanging freely on the retention system.
Raise the 4-kg (8.8-lb) drop weight to a height of 0.6 m (2 ft) from the stop anvil and release it, so that it impacts the stop anvil.
Record the maximum elongation of the retention system during the impact. A marker system or a displacement transducer, as shown in Figure 8 of this part, are two methods of measuring the elongation.
Copyright ©2024 LegalFix. All rights reserved. LegalFix is not a law firm, is not licensed to practice law, and does not provide legal advice, services, or representation. The information on this website is an overview of the legal plans you can purchase—or that may be provided by your employer as an employee benefit or by your credit union or other membership group as a membership benefit.
LegalFix provides its members with easy access to affordable legal services through a network of independent law firms. LegalFix, its corporate entity, and its officers, directors, employees, agents, and contractors do not provide legal advice, services, or representation—directly or indirectly.
The articles and information on the site are not legal advice and should not be relied upon—they are for information purposes only. You should become a LegalFix member to get legal services from one of our network law firms.
You should not disclose confidential or potentially incriminating information to LegalFix—you should only communicate such information to your network law firm.
The benefits and legal services described in the LegalFix legal plans are not always available in all states or with all plans. See the legal plan Benefit Overview and the more comprehensive legal plan contract during checkout for coverage details in your state.
Use of this website, the purchase of legal plans, and access to the LegalFix networks of law firms are subject to the LegalFix Terms of Service and Privacy Policy.