ASTM C1270-97(R2021) pdf free download

ASTM C1270-97(R2021) pdf free download.Standard Practice for Detection Sensitivity Mapping of In-Plant Walk-Through Metal Detectors
1. Scope
1.1 This practice covers a procedure for determining the weakest detection path through the portal aperture and the worst-case orthogonal orientation of metallic test objects. It results in detection sensitivity maps, which model the detection zone in terms related to detection sensitivity and identify the weakest detection paths. Detection sensitivity maps support sensitivity adjustment and performance evaluation procedures (see Practices C1269 and C1309). N OTE 1—Unsymmetrical metal objects possessing a primary longitu- dinal component, such as handguns and knives, usually have one particular orientation that produces the weakest detection signal. The orientation and the path through the detector aperture where the weakest response is produced may not be the same for all test objects, even those with very similar appearance. N OTE 2—In the case of multiple specified test objects or for test objects that are orientation sensitive, it may be necessary to map each object several times to determine the worst-case test object or orientation, or both. 1.2 This practice is one of several developed to assist operators of walk-through metal detectors with meeting the metal detection performance requirements of the responsible regulatory authority. (See Appendix X2) 1.3 This practice is neither intended to set performance levels, nor limit or constrain operational technologies. 1.4 This practice does not address safety or operational issues associated with the use of walk-through metal detectors. 1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.6 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
3. Terminology
3.1 Definitions ofTerms Specific to This Standard: 3.1.1 clean-tester, n—a person who does not carry any extraneous metallic objects that would significantly alter the signal produced when the person carries a test object. 3.1.1.1 Discussion—By example but not limitation, such extraneous metallic objects may include: metallic belt buckles, metal buttons, cardiac pacemakers, coins, metal frame eye glasses, hearing aids, jewelry, keys, mechanical pens and pencils, shoes with metal shanks or arch supports, metallic surgical implants, undergarment support metal, metal zippers, etc. In the absence of other criteria, a clean tester passing through a metal detector shall not cause a disturbance signal greater than 10 % of that produced when carrying the critical test object through the detector. Test objects requiring very high sensitivity settings for detection require more complete elimination of extraneous metal to obtain less than 10 % signal disturbance. 3.1.1.2 Discussion—The tester shall have a weight between 50 to 104 kg (110 to 230 lb) and a height between 1.44 to 1.93 m (57 to 75 in.). Should a given detector be sensitive to body size because of design or desired sensitivity, the physical size of testers should be smaller and within a narrower range. 3.1.1.3 Discussion—It is recommended that the clean tester be surveyed with a high sensitivity hand-held metal detector to ensure that no metal is present. 3.1.2 critical orientation, n—the orthogonal orientation of a test object that produces the smallest detection signal or weakest detection anywhere in the detection zone; the orthogo- nal orientation of a test object that requires a higher sensitivity setting to be detected compared to the sensitivity setting required to detect the object in all other orthogonal orienta- tions. See Fig. 1 for handgun orientations.3.1.2.1 Discussion—Critical orientations are determined by testing using a mapping procedure such as described in this practice. 3.1.2.2 Discussion—The term critical orientation can refer to the worst case orthogonal orientation in a single test path or the worst case orthogonal orientation for all the test paths (the entire detection zone). The two are coincident in the critical test path. 3.1.3 critical sensitivity setting, n—the lowest sensitivity setting of a detector at which the critical test object in its critical orientation is consistently detected (ten out of ten test passes) when passed through the detection zone on the critical test path.