ORLANDO, FL, Feb. 28, 2013 — With the exponential growth of fiber-optic telecommunications comes the need for well-trained installation and service personnel. Guiding those employees will be the new ANSI Z136.2 laser safety standard, available from the Laser Institute of America.
The release of the standard, timed to coincide with the annual meeting of the Z136 committee March 17 in Orlando, has been more than 10 years in the making.
“Fiber is going everywhere now,” says Ron Petersen, who spearheaded the team that crafted the guidelines. “With (Verizon) Fios and numerous other systems, and now even for going back and forth between base stations for the switch for cellular telephone, it is being used for absolutely everything.”
Since the early ‘90s, the technology “has evolved from a visionary laboratory technology to a mature industry standard for telecommunication transport,” notes Paul Testagrossa, secretary of the Z136.2 subcommittee and an engineer with Alcatel-Lucent. “This has been made possible with smaller, more powerful laser sources and trends to single-mode from multimode fiber. This has led to more hazard concerns (due to the) higher energy and higher power density associated with these systems.”
The standard provides guidance for the safe use, maintenance, service, and installation of optical communications systems utilizing laser diodes or LEDs operating at wavelengths between 0.6 microns and 1 mm. Optical communication systems include end-to-end optical fiber-based links, fixed terrestrial point-to-point free-space links or a combination of both.
“Usually it’s just purchased components strung together into a system,” says Petersen, who was head of the wireless and optical technologies safety department for about 30 of his almost 41 years at Bell Labs. “This gives some guidance for what has to be done for certain Class devices. Part of the problem is that the end-to-end system is Class 1, or hazard level 1, but individual components are not. As people build and test a system, they really ought to be aware of what the possible risks are. Labeling on the equipment bays is important.”
This standard is intended to be used by those who assemble the end-to-end system and by service, maintenance, and other personnel who may come in contact with such systems where access is in uncontrolled, controlled and restricted locations. It provides detailed safety information for systems where optical energy may be accessible and where source parameters are uncertain or not under the control of the user. Control measures commensurate with the specific hazard level (optical fiber links) and access level (free-space links) are provided. Most evaluations can be carried out analytically. A number of representative examples of hazard evaluation are provided in the appendices.
The origins of the Z136.2 standard go back to 1988, when Petersen became chair of the group. “At that time, there was sort of little interest in it, but I and (LIA safety instructor) Dave Sliney put together a document, pointing out what the risk could be and the fact that this isn’t even addressed anywhere because it’s completely different from conventional lasers. In most cases, the beam is divergent — it’s less of a hazard to the eye. So instead of having classes, we came up with a whole series of nomenclature called service groups.”
In this standard, “the nomenclature has changed. Instead of using service groups, because of influence from IEC, we chose hazard classes to be consistent with international documents. Where the IEC (guidelines are) mainly for manufacturers, this one is more for users,” particularly those who are splicing fiber.
“While the physical handling aspects have progressed from being manual labor intensive to automated processes for connection, splicing, repair, etc., hazardous conditions for services personnel need to be addressed,” Testagrossa adds. “Especially considering that laser energy in an optical fiber communication system is typically in the infrared region, where the potential for serious eye injury exists.”
LIA, the recognized industry leader in laser advocacy and safety education since 1968, serves as secretariat of the Accredited Standards Committee that develops the Z136 series of laser safety standards. To order the .2 ($130 for LIA members, $150 for non-members, ISBN# 978-0-912035-68-0), visit www.lia.org/ANSI or call LIA at 1.800.34.LASER.
Laser Institute of America (LIA) is the professional society for laser applications and safety serving the industrial, educational, medical, research and government communities throughout the world since 1968. www.lia.org, 13501 Ingenuity Drive, Ste 128, Orlando, FL 32826, +1.407.380.1553.