1、 American National Standard Recommended Practice for Laser Safety Measurements for Hazard Evaluation American National StandardANSI Z136.4 2010 ANSIZ136.4 2010 Revision of ANSI Z136.4-2005 American National Standard Recommended Practice for Laser Safety Measurements for Hazard Evaluation Secretariat
2、 Laser Institute of America Approved April 22, 2010 American National Standards Institute, Inc. American National Standard An American National Standard implies a consensus of those substantially concerned with its scope and provisions. An American National Standard is intended as a guide to aid the
3、 manufacturer, the consumer, and the general public. The existence of an American National Standard does not in any respect preclude anyone, whether or not he or she has approved the standard, from manufacturing, marketing, purchasing, or using products, processes or procedures not conforming to the
4、 standard. American National Standards are subject to periodic review and users are cautioned to obtain the latest editions. CAUTION NOTICE: This American National Standard may be revised or withdrawn at any time. The procedures of the American National Standards Institute require that action be tak
5、en periodically to reaffirm, revise, or withdraw this standard no later than five years from the date of publication. Purchasers of American National Standards may receive current information on all standards by calling or writing the American National Standards Institute. Published by Laser Institu
6、te of America 13501 Ingenuity Drive, Suite 128 Orlando, FL 32826 ISBN: #0-912035-78-1 Copyright 2010 by Laser Institute of America. All rights reserved. No part of this publication may be copied or reproduced in any form, including an electronic retrieval system or be made available on the Internet,
7、 a public network, by satellite, or otherwise, without the prior written permission of the publisher. Printed in the United States of America. i Foreword (This introduction is not a normative part of ANSI Z136.4-2010, American National Standard Recommended Practice for Laser Safety Measurements for
8、Hazard Evaluation.) In 1968, the American National Standards Institute (ANSI) approved the initiation of the Safe Use of Lasers Standards Project under the sponsorship of the Telephone Group. Prior to 1985, Z136 standards were developed by ANSI Committee Z136 and submitted for approval and issuance
9、as ANSI Z136 standards. Since 1985, Z136 standards are developed by the ANSI Accredited Standards Committee (ASC) Z136 for Safe Use of Lasers. A copy of the procedures for development of these standards can be obtained from the secretariat, Laser Institute of America, 13501 Ingenuity Drive, Suite 12
10、8, Orlando, FL 32826 or viewed at www.z136.org. The present scope of ASC Z136 is to protect against hazards associated with the use of lasers and optically radiating diodes. ASC Z136 is responsible for the development and maintenance of this standard. In addition to the consensus body, ASC Z136 is c
11、omposed of standards subcommittees (SSC) and technical subcommittees (TSC) involved in Z136 standards development and an editorial working group (EWG). At the time of this printing, the following standards and technical subcommittees were active: SSC-1 Safe Use of Lasers (parent document) SSC-2 Safe
12、 Use of Lasers and LEDs in Telecommunications Applications SSC-3 Safe Use of Lasers in Health Care SSC-4 Measurements and Instrumentation SSC-5 Safe Use of Lasers in Educational Institutions SSC-6 Safe Use of Lasers Outdoors SSC-7 Eyewear and Protective Barriers SSC-8 Safe Use of Lasers in Research,
13、 Development, and Testing SSC-9 Safe Use of Lasers in Manufacturing Environments SSC-10 Safe Use of Lasers in Entertainment, Displays, and Exhibitions TSC-1 Biological Effects and Medical Surveillance TSC-2 Hazard Evaluation and Classification TSC-4 Control Measures and Training TSC-5 Non-Beam Hazar
14、ds TSC-7 Analysis and Applications EWG Editorial Working Group ii The six standards currently issued are: ANSI Z136.1-2007, American National Standard for Safe Use of Lasers (replaces ANSI Z136.1-2000) ANSI Z136.3-2005, American National Standard for Safe Use of Lasers in Health Care Facilities (rep
15、laces ANSI Z136.3-1996) ANSI Z136.4-2010, American National Standard Recommended Practice for Laser Safety Measurements for Hazard Evaluation (replaces ANSI Z136.4-2005) ANSI Z136.5-2009, American National Standard for Safe Use of Lasers in Educational Institutions (replaces ANSI Z136.5-2000) ANSI Z
16、136.6-2005, American National Standard for Safe Use of Lasers Outdoors (replaces ANSI Z136.6-2000) ANSI Z136.7-2008, American National Standard for Testing and Labeling of Laser Protective Equipment (first edition) This American National Standard Recommended Practice provides guidance for optical me
17、asurements associated with laser safety requirements. The information provided in this recommended practice is intended to assist users who are entrusted with the responsibility of conducting laser hazard evaluations to ensure that appropriate control measures are implemented. Laser safety requireme
18、nts and the rationale for them are specified in ANSI Z316.1 American National Standard for Safe Use of Lasers. The procedures and methodologies described in this recommended practice are based on requirements previously established in ANSI Z136.1. As the name implies, this recommended practice conta
19、ins recommendations that will lead to the desired end result. On many occasions, there is more than one measurement approach to achieve the end result, and the recommended measurement techniques in this recommended practice should be viewed as plausible practical options, and not necessarily as the
20、exclusive techniques to perform a given task. This recommended practice has been published as part of the ANSI Z136 series of laser safety standards. The basic document is the ANSI Z136.1, American National Standard for Safe Use of Lasers. In general, this recommended practice may be used as a suppl
21、ement to ANSI Z136.1 when additional details on laser safety measurements are desired. This standard is expected to be periodically revised as new information and experience in the use of lasers is gained. Future revisions may have modified methodology, and use of the most current document is highly
22、 recommended. iii While there is considerable compatibility among existing laser safety standards, some requirements differ among state, federal, and international standards and regulations. These differences may have an effect on the particulars of the applicable control measures. Occasionally ques
23、tions may arise regarding the meaning or intent of portions of this standard as it relates to specific applications. When the need for an interpretation is brought to the attention of the secretariat, the secretariat will initiate action to prepare an appropriate response. Since ANSI Z136 standards
24、represent a consensus of concerned interests, it is important to ensure that any interpretation has also received the concurrence of a balance of interests. For this reason, the secretariat is not able to provide an instant response to interpretation requests except in those cases where the matter h
25、as previously received formal consideration. Requests for interpretations and suggestions for improvements of the standard are welcome. They should be sent to ASC Z136 Secretariat, Laser Institute of America, 13501 Ingenuity Drive, Suite 128, Orlando, FL 32826. This standard was processed and approv
26、ed for submittal to ANSI by ASC Z136. Committee approval of the standard does not necessarily imply that all members voted for its approval. Ron Petersen, Committee Chair Sheldon Zimmerman, Committee Vice-Chair Robert Thomas, Committee Secretary iv Notice (This notice is not a normative part of ANSI
27、 Z136.4-2010, American National Standard Recommended Practice for Laser Safety Measurements for Hazard Evaluation.) Z136 standards and recommended practices are developed through a consensus standards development process approved by the American National Standards Institute. The process brings toget
28、her volunteers representing varied viewpoints and interests to achieve consensus on laser safety related issues. As secretariat to ASC Z136, the Laser Institute of America (LIA) administers the process and provides financial and clerical support to the committee. The LIA and its directors, officers,
29、 employees, members, affiliates, and sponsors, expressly disclaim liability for any personal injury, property, or other damages of any nature whatsoever, whether special, indirect, consequential, or compensatory, directly or indirectly resulting from the publication, use of, or reliance on this docu
30、ment or these standards. The LIAs service as secretariat does not constitute, and LIA does not make any endorsement, warranty, or referral of any particular standards, practices, goods, or services that may be referenced in this document. The LIA also makes no guarantee or warranty as to the accurac
31、y or completeness of any information published herein. The LIA has no power, nor does it undertake to police or enforce compliance with the contents of this document. In issuing and making this document available, the LIA is not undertaking to render professional or other services for or on behalf o
32、f any person or entity. Nor is the LIA undertaking to perform any duty owed by any person or entity to someone else. Anyone using this document should rely on his or her own independent judgment or, as appropriate, seek the advice of a competent professional in determining the exercise of reasonable
33、 care in any given circumstances. v Participants At the time it approved this standard, ASC Z136 had the following members: Organization Represented Name of Representative Academy of Laser Dentistry Joel White Altos Photonics, Inc. Lucian Hand American Academy of Dermatology Mark Nestor American Col
34、lege of Obstetricians lightguide. point source. For purposes of this document, a source with an angular subtense at the cornea equal to or less than alpha-min (min), i.e., 1.5 mrad. point source viewing. The viewing condition whereby the angular subtense of the source, , is equal to or less than the
35、 limiting angular subtense, min. power. The rate at which energy is emitted, transferred, or received. Unit: watts (joules per second). Symbol: pulse duration. The duration of a laser pulse; usually measured as the time interval between the half-power points on the leading and trailing edges of the
36、pulse. Symbol: t pulse-repetition frequency (PRF). The number of pulses occurring per second, expressed in hertz. Symbol: F pulsed laser. A laser which delivers its energy in the form of a single pulse or a train of pulses. In this recommended practice, the duration of a pulse is less than 0.25 s. Q
37、-switch. A device for producing very short ( 1-250 ns), intense laser pulses by enhancing the storage and dumping of electronic energy in and out of the lasing medium, respectively. Q-switched laser. A laser that emits short ( 1-250 ns), high-power pulses by means of a Q-switch. radian (rad). A unit
38、 of angular measure equal to the angle subtended at the center of a circle by an arc whose length is equal to the radius of the circle. 1 radian = 57.3 degrees; 2 radian = 360 degrees. radiance. Radiant flux or power output per unit solid angle per unit area expressed in watts per square centimeter
39、per steradian (Wcm-2sr-1). Symbol: L radiant energy. Energy emitted, transferred, or received in the form of radiation. Unit: joules (J). Symbol: Q radiant exposure. Surface density of the radiant energy received, expressed in units of joules-per- square centimeter (Jcm-2). Symbol: H radiant power.
40、Power emitted, transferred or received in the form of radiation. Unit: watts (W). Also called radiant flux. Symbol: radiometry. For purposes of this recommended practice, the measurement of infrared, visible, and ultraviolet radiation. Rayleigh scattering. Scattering of radiation in the course of it
41、s passage through a medium containing particles whose sizes are small compared with the wavelength of the radiation. AMERICAN NATIONAL STANDARD Z136.4-2010 9 reflectance. The ratio of total reflected radiant power to total incident power. Also called reflectivity. reflection. Deviation of radiation
42、following incidence on a surface. refraction. The bending of a beam of light in transmission at an interface between two dissimilar media or in a medium whose refractive index is a continuous function of position (graded index medium). refractive index (of a medium). Denoted by n, the ratio of the v
43、elocity of light in vacuum to the phase velocity in the medium. Also called index of refraction. repetitive-pulse laser. A laser with multiple pulses of radiant energy occurring in a sequence. retina. The sensory tissue that receives the incident image formed by the cornea and lens of the human eye.
44、 retinal hazard region. Optical radiation with wavelengths between 0.4 m and 1.4 m, where the principal hazard is usually to the retina. scanning laser. A laser having a time varying direction, origin, or pattern of propagation with respect to a stationary frame of reference. solid angle. The three-
45、dimensional angular spread at the vertex of a cone measured by the area intercepted by the cone on a unit sphere whose center is the vertex of the cone. Unit: steradians (sr). Symbol: source. A laser or a laser-illuminated reflecting surface. specular reflection. A mirror-like reflection. steradian
46、(sr). The unit of measure for a solid angle. There are 4 steradians about any point in space. T1. The exposure duration (time) beyond which MPEs based upon thermal injury are replaced by MPEs based upon photochemical injury to the retina. T2. The exposure duration (time) beyond which extended-source
47、 MPEs based upon thermal injury are expressed as a constant irradiance. Tmax. The total expected or anticipated exposure duration (See ANSI Z136.1-2007 Section 3 for classification and Section 8 for intended use determination.) Tmaxmay differ depending upon its use. telescopic viewing. Viewing an ob
48、ject from a long distance with the aid of an optical system that increases the visual size of the image. The system (e.g., binoculars) generally collects light through a large aperture, thus magnifying hazards from large-beam, collimated lasers. AMERICAN NATIONAL STANDARD Z136.4-2010 10 tmin. For a
49、pulsed laser, the maximum duration for which the MPE is the same as the MPE for a 1 ns exposure. For thermal biological effects, this corresponds to the “thermal confinement duration” during which heat flow does not significantly change the absorbed energy content of the thermal relaxation volume of the irradiated tissue. transmittance. The ratio of transmitted power (energy) to incident power (energy). Symbol: ultraviolet radiation. In this document, electromagnetic radiation with wavelengths between 180 and 400 nm (shorter than those of visible radiation). visi