| (A) any service and maintenance of lasers that may affect the output power or operating characteristics; or (B) whenever deliberate modifications are made that could change the laser class and affect the output power or operating characteristics. (4) ensuring maintenance and other practices required for safe operation of the laser(s) are performed; (5) ensuring the proper use of protective eyewear and other safety measures; and (6) ensuring compliance with the requirements in this section and with any engineering or operational controls specified by the registrant. (r) Requirements for protection against Class 3b or 4 lasers and IPL device radiation. These requirements are for Class 3b or 4 lasers and IPL devices in their intended mode of operation and include special requirements for service, testing, maintenance, and modification. During some operations, certain engineering controls may be inappropriate. In situations where an engineering control may be inappropriate, for example, during medical procedures or surgery, the LSO shall specify alternate controls to obtain equivalent safety protection. (1) MPE. Each registrant or user of any laser shall not permit any individual to be exposed to levels of laser or collateral radiation higher than are specified in ANSI Z136.1-2000, Safe Use of Lasers and Title 21, CFR, §1040.10 respectively. (2) Instructions to personnel. Personnel operating each laser presently being used or listed on the registrant's current inventory, shall be provided with written instructions for safe use, including clear warnings and precautions to avoid possible exposure to laser and collateral radiation in excess of the MPE, as delineated in ANSI Z136.1-2000, Safe Use of Lasers and the collateral limits listed in Title 21, CFR, §1040.10. The instructions to personnel shall be maintained in accordance with subsection (ee) of this section for inspection by the agency. (3) Engineering controls. (A) Protective housing. (i) Each laser shall have a protective housing that prevents human access during the operation to laser and to collateral radiation that exceeds the limits of Class 1 lasers as delineated in ANSI Z136.1-2000, Safe Use of Lasers and Title 21, CFR, Part 1040.10, respectively, wherever and whenever such human access is not necessary in order for the laser to perform its intended function. (ii) Wherever and whenever human access to laser radiation levels that exceed the limits of Class 1 is necessary, these levels shall not exceed the limits of the lowest laser class necessary to perform the intended function(s). (B) Safety interlocks. (i) A safety interlock, that shall ensure that radiation is not accessible above MPE limits as delineated in ANSI Z136.1-2000, Safe Use of Lasers, shall be provided for any portion of the protective housing that by design can be removed or displaced during normal operation or maintenance, and thereby allows access to radiation above the MPE limits. (ii) Adjustment during operation, service, testing, or maintenance of a laser containing interlocks shall not cause the interlocks to become inoperative or the radiation to exceed MPE limits outside protective housing except where a laser controlled area as specified in subparagraph (E) of this paragraph is established. (iii) For pulsed lasers, interlocks shall be designed so as to prevent firing of the laser; for example, by dumping the stored energy into a dummy load. (iv) For continuous wave lasers, the interlocks shall turn off the power supply or interrupt the beam; for example, by means of shutters. (v) An interlock shall not allow automatic accessibility of radiation emission above MPE limits when the interlock is closed. (vi) Either multiple safety interlocks or a means to preclude removal or displacement of the interlocked portion of the protective housing upon interlock failure shall be provided, if failure of a single interlock would allow the following: (I) human access to levels of laser radiation in excess of the accessible emission limit of Class 3a laser radiation; or (II) laser radiation in excess of the accessible emission limits of Class 2 to be emitted directly through the opening created by removal or displacement of that portion of the protective housing. (C) Viewing optics and windows. (i) All viewing ports, viewing optics, or display screens included as an integral part of an enclosed laser or laser product shall incorporate suitable means, (such as interlocks, filters, or attenuators, to maintain the laser radiation at the viewing position at or below the applicable MPE as delineated in ANSI Z136.1-2000, Safe Use of Lasers and the collateral limits listed in Title 21, CFR, §1040.10, under any conditions of operation of the laser. (ii) All collecting optics, such as lenses, telescopes, microscopes, endoscopes, etc., intended for viewing use with a laser shall incorporate suitable means, such as interlocks, filters, or attenuators, to maintain the laser radiation transmitted through the collecting optics to levels at or below the appropriate MPE, as delineated in ANSI Z136.1-2000, Safe Use of Lasers. Normal or prescription eyewear is not considered collecting optics. (D) Warning systems. Each Class 3b or 4 laser or laser product shall provide visual or audible indication during the emission of accessible laser radiation. In the case of Class 3b lasers, except those that allow access only to less than 5 milliwatt (mW) peak visible laser radiation, and Class 4 lasers, this indication shall be sufficient prior to emission of such radiation to allow appropriate action to avoid exposure. Any visual indicator shall be clearly visible through protective eyewear designed specifically for the wavelength(s) of the emitted laser radiation. If the laser and laser energy source are housed separately and can be operated at a separation distance of greater than two meters, both laser and laser energy source shall incorporate visual or audible indicators. The visual indicators shall be positioned so that viewing does not require human access to laser radiation in excess of the MPE, as delineated in ANSI Z136.1-2000, Safe Use of Lasers. (E) Controlled area. With a Class 3b laser, except those that allow access only to less than 5 mW visible peak power, or Class 4 laser, a controlled area shall be established when exposure to the laser radiation in excess of the MPE, as delineated in ANSI Z136.1-2000, Safe Use of Lasers or the collateral limits listed in Title 21, CFR, §1040.10 is possible. The controlled area shall meet the following requirements, as applicable. (i) The area shall be posted as required by subsection (v) of this section. (ii) Access to the controlled area shall be restricted. (iii) For Class 4 indoor controlled areas, latches, interlocks, or other appropriate means shall be used to prevent unauthorized entry into controlled areas. (I) Such measures shall be designed to allow rapid egress by the laser personnel at all times and admittance to the controlled area in an emergency condition. For such emergency conditions, a control-disconnect switch or equivalent device (panic button) shall be available for deactivating the laser. (II) Where safety latches or interlocks are not feasible or are inappropriate, for example during medical procedures, such as surgery, the following shall apply. (-a-) All authorized personnel shall be trained in laser safety and appropriate personal protective equipment shall be provided upon entry. (-b-) A door, blocking barrier, screen, or curtains shall be used to block, screen, or attenuate the laser radiation at the entryway. The level at the exterior of these devices shall not exceed the applicable MPE, as delineated in ANSI Z136.1-2000, Safe Use of Lasers, nor shall personnel experience any exposure above the MPE immediately upon entry. (-c-) At the entryway there shall be a visible or audible signal indicating that the laser is energized and operating at Class 4 levels. A lighted laser warning sign, flashing light (visible through laser protective eyewear), and other appropriate signage are some of the methods to accomplish this requirement. Alternatively, an entryway warning light assembly may be interfaced to the laser in such a manner that one light will indicate when the laser is not operational (high voltage off) and by an additional light when the laser is powered up (high voltage applied, but no laser emission) and by an additional (flashing optional) light that activates when the laser is operating. (iv) For Class 4 indoor controlled areas, during tests requiring continuous operation, the individual in charge of the controlled area shall be permitted to momentarily override the safety interlocks to allow access to other authorized personnel if it is clearly evident that there is no optical radiation hazard at the point of entry, and if the necessary protective devices are being worn by the entering personnel. Cont'd... |
