At times, the nature of laser hazard classifications can seem perplexing. But, in terms of individual laser classes, Class 1 lasers have proved to cause the most confusion — by far. In many cases, the use of obscure vocabulary regarding these lasers is the cause of the uncertainty. For example, “Class 1” and “Class 1 product” are used interchangeably, and “embedded laser” is synonymous with both of these terms. In reality, with only a few exceptions, members of the public rarely encounter Class 1 lasers. On the other hand, Class 1 laser products such as laser markers, printers, and scanners are frequently used. Per ANSI Z136.1 Safe Use of Lasers-2022, a Class 1 laser is described as: 3.3.1.1 Class 1. Any laser or laser system that cannot emit accessible laser radiation levels during operation in excess of the applicable Class 1 (accessible emission limit) for any emission duration within the maximum duration inherent in the design or intended use of the laser or laser system is a Class 1 laser or laser system during operation. A Class 1 laser or laser system is exempt from user control measures with the exception of requirements applicable for embedded higher-class lasers. Accessible emission limit is the maximum accessible emission level permitted within a particular laser hazard class. In simple terms, Class 1 lasers do not emit more than a few hundred microwatts. Courtesy of iStock.com/onuma Inthapong. On the other hand, “Class 1 products” — although the Z136 series does not use that title — are characterized by an enclosed laser that has a higher classification than the laser system in which it is incorporated. In these systems, the lower classification is appropriate, since the engineering features limit the accessible emission. The public may know Class 1 products as embedded lasers. All of this to say, Class 1 lasers and Class 1 products are the subjects of many questions, most of which are familiar to laser safety professionals. “Do I need labeling?” is among the most common questions, and one of the easiest to answer. Since Class 1 products do not present a hazard to users during normal operation, they do not require manufacturers to use a hazard label — placing them in contrast to Class II, IIIa, IIIb, and IV laser products. Still, some laser product manufacturers prefer to place a Class 1 label on their products. In other cases, manufacturers will place a Class 4 Danger label on their Class 1 industrial products, even though these systems are completely safe for use. Although this may send a mixed message, the Class 4 Danger label pertains to the internal laser system alone. Therefore, if a manufacturer places a label on the outside of the unit, it must either be clear that it governs the internal laser, or it must be placed in an appropriate location on the product. Often, this labeling mechanism creates an avoidable challenge for the end user, who may question the safety of a mainstay product as a result of a confusing or poorly located label. The laser safety officer: Assessing need Z136.1-2022 Appendix A, section A1.1 introduces the notion of designating a laser safety officer (LSO) for Class 1 lasers and products. Under certain circumstances, according to the standard, an operator may opt to designate an LSO in certain situations, or upon the need for certain protocols. These include instances when a service is performed on a laser system that has an embedded Class 3B or 4 laser. In these cases, “Management may designate the service person requiring access to the embedded laser as the LSO. In any case, there shall be a designated LSO for all circumstances of operation, maintenance, and service of a Class 3B or 4 laser or laser system.” The ambiguity of this portion of the standard is evident: It begins with an offer, yet it ends with an instruction. It also fails to address who — the operator, an LSO, a third-party vendor, or another professional — is performing the service. Though the use of a third-party vendor could hypothetically enable a company to bypass the process of finding and then training an LSO, the services of these trained and certified officers are still needed. Section 4.4.2.7.3 Enclosed Beam Path (All Classes) of Z136.1-2022 makes this clear. Simply, once protective barriers are removed from a Class 1 product or system, the responsibility shifts solely to the LSO. This scenario could emerge during servicing or in other instances in which protective housing requirements are more relaxed. While the servicing of a laser is a common occurrence, the dangers are serious and must be managed. Once barriers and/or protective housings are removed, and all members of the service staff are wearing laser protective eyewear, the perception of risk can exist to those working around the area. The use of temporary barriers and control areas becomes important in these instances. If the perception of risk-needs is unaddressed, a simple accommodation to the laser system, such as that which occurs for standard servicing, may generate undue worry and even trigger regulatory inspections. Class 1 in context Though many safety requirements apply more obviously to lasers beyond Class 1, for example, Class 3B and 4 lasers, there is little doubt regarding the standard protocols and best practices. According to 4.4.3.9 Service Personnel (All Classes), “Personnel who require access to Class 3B or 4 lasers or laser systems enclosed within a protective housing or protected area enclosure shall comply with the appropriate control measures of the enclosed or embedded laser or laser system. The LSO shall confirm that service personnel have the education and safety training commensurate with the class of the laser or laser system contained within the protective housing.” It is also clear that any in-house members of staff who perform service work on or with Class 3B or Class 4 lasers are considered laser operators and, as a result, require appropriate training. For outside vendors, though requirements are harder to establish, this task often falls to the LSO, who can resolve it intuitively. While not all LSOs will naturally question the laser safety training of these third-party service personnel and whether they have received appropriate laser safety training, this should be considered a best practice. Third-party vendor training is the responsibility of the employing firm, not the company or institution for which they are working. At Lawrence Berkeley National Laboratory, for example, I would meet with outside service staff to ensure that each member of the staff understood our facility-specific safety expectations and requirements. Having these third-party staff members sign a temporary work document, or even a service standard operating procedure to verify compliance, often yielded some insight into their firm’s laser safety program. Though these individuals often traveled without warning signs to display or even laser-protective eyewear, understanding their background helped facilitate their transition into working at our facility. Chain of command Per the standards referenced earlier, the LSO can work as an in-house staff member to perform services. In my experience, this is an unusual occurrence. If an LSO can be an equipment supervisor, for example, a large facility is apt to have several eligible LSOs. For this reason, it may be more viable to delegate the role of the LSO to the person who drafted the facility’s service standard operating procedure. The LSO could also be an outside or independent professional. Necessary knowledge For all laser users and prospective users, it is important to know that limited open beam paths can achieve Class 1 status. Once again, per the Z136.1 Standard, “Lasers or laser systems intended for a specific use may be designated Class 1 by the LSO on the basis that use for a limiting exposure duration of Tmax is less than 100 s. In that instance, the accessible laser radiation shall not exceed the corresponding Class 1 [accessible emission limit] for any emission duration within the maximum duration inherent in that specific use.” One simplified interpretation of this standard is that the LSO can classify limited beam paths — such as some robots on assembly lines, or industrial laser systems whose footprint prevents anyone from getting close enough to be exposed during normal operation — as a Class 1 system. An additional wrinkle to Class 1 laser and laser product safety is that Class 1 laser products can be difficult to narrow down. Especially in a university setting, for example, common devices such as 3D printers, laser cutters, laser scanning confocal microscopes, and cell sorters — each of which falls into the category of a Class 1 laser product — are perceived as tools by their users, and not necessarily a laser device. Only during servicing, or other instances in which a beam may be exposed, is the perception of these devices likely to differ. With all this in mind, let us close with the question: Does the use of a Class 1 product require an LSO? I believe that contrary to what most users think, if the product contains embedded Class 3B and Class 4 lasers that must be accessed while energized, the Z136 series says YES!