While product safety and reliability are core principles of virtually every manufacturer designing equipment for the telecom industry, the Telcordia Generic Requirements (GRs) that ensure the integrity of such devices and systems are not commonly understood by manufacturers around the globe.
As an increasing amount of equipment used in telecommunications networks is being produced in different parts of the world, recognizing and adhering to these standards and requirements is essential to competing in this ever-expanding market.
Among these requirements is the NEBS family of requirements, which stands for Network Equipment Building System. Unlike more traditional product safety standards, compliance to the NEBS family of standards ensures the personal safety of equipment operators and service technicians and the protection of facilities housing equipment, all while ensuring the integrity of an overall telecommunications network. This family of requirements is what members of the Telecommunication Carrier Group (TCG), such as Verizon and AT&T, and smaller local service providers use to evaluate telecommunications equipment to ensure network integrity and protect against hazards associated with the location of equipment.
It is this all-encompassing focus on safety, reliability and performance of network equipment and its impact on the environment of telecom facilities that distinguishes NEBS requirements from other telecommunications standards. NEBS requirements are designed to:
- Protect personnel
- Streamline equipment design and installation
- Prevent service outages and interference in a network caused by incompatible equipment
- Reduce the risks of fire in network facilities
- Guard against the potential negative impacts on equipment from extreme temperatures, vibration and airborne contamination
- Support equipment compatibility with the network’s electrical environment.
Like other industry requirements, meeting NEBS requirements can positively impact a manufacturer’s bottom line. NEBS requirements consist of three levels of compliance, each ensuring a different stage of network protection. Understanding in advance the required level of compliance for a particular product can help a manufacturer minimize product development, installation and maintenance costs. Increasingly, telecommunications equipment manufacturers around the world are requiring their component suppliers to demonstrate compliance with NEBS and including this stipulation in requests for proposal (RFPs) and supplier contracts. In fact, requirements are beginning to apply to both wire line installations as well as wireless applications.
Understanding Levels of Compliance
As most TCG members require demonstration of NEBS compliance prior to the purchase and/or deployment on their telecommunication network infrastructure, equipment manufacturers document compliance to NEBS requirements by having testing performed by an ISO 17025 accredited third-party test laboratory. In certain circumstances, NEBS-related testing can be performed in-house, assuming an internal laboratory is properly accredited to ISO 17025. However, some TCG members require all testing to be performed or witnessed by an accredited independent test laboratory (ITL).
NEBS requirements apply to telecommunications equipment installed in a Central Office (CO) environment, certain Outside Plant applications (OSP), and Customer Premises Equipment (CPE). There are generally two primary GRs that apply to most equipment designated for use in a CO: GR-1089-CORE (Issue 6), which covers electromagnetic compatibility, electrical transients and electrical safety; and GR-63-CORE (Issue 4), which covers physical requirements. GR-1089-CORE and GR-63-CORE together are commonly referred to as the “NEBS Criteria.” It’s important to understand that individual TCGs may have additional requirements beyond those found in GR-1089-CORE and GR-63-CORE.
Helping to speed and simplify the compliance process without jeopardizing network reliability in the deployment of new equipment, the Telcordia special report SR-3580, NEBS Criteria Levels, divides NEBS requirements into three levels of compliance.
- Level 1 is the minimum acceptable level of NEBS environmental compatibility needed to preclude hazards and degradation of a network facility and hazards to personnel. Level 1 comprises only safety and risk criteria. Conformance to Level 1 does not assure equipment operability or service continuity. Level 1 is typically used by service providers for early deployment into their COs and/or interoperability laboratories, and to allow collocaters to install equipment in a central office. A collocater is a company that rents space in a central office and provides some type of communications service (such as Internet access or long distance).
- Level 2 is the minimum level of NEBS environmental compatibility needed to provide some limited assurance of equipment operability within the network facility environment. This assurance of operability is limited to the controlled or normal environments as defined by the criteria. Rarely a focus of customers, Level 2 includes all requirements of Level 1 with some added level of operability reliability.
- Level 3 is the minimum level of NEBS environmental compatibility needed to provide maximum assurance of equipment operability within the network facility environment. The Level 3 criteria provide the highest assurance of product operability. Level 3 criteria are suited for equipment applications that demand minimal service interruptions over the equipment’s life. Most TCGs require NEBS Level 3 prior to acceptance/installation on the network as they require this level of compliance for equipment operation in the central office, but not collocated equipment.
While SR-3580 identifies the tests required by the three levels, most equipment manufacturers submit their equipment to be evaluated to NEBS Level 3. Even in pursuing the highest assurance of product operability that Level 3 provides, manufacturers should know where their product is going to be deployed on a network: in a CO operated by telecom carriers, outside plant environment or customer premises. The setting of product deployment determines the tests that need to be performed to meet NEBS requirements. For example, specific environmental testing, in accordance with GR-63-CORE, simulates exposure to extreme environments that include high/low temperatures, high humidity, shock and exposure, fire ignition and flame spread, seismic conditions and airborne contaminates. By understanding the testing process, and the additional tests that may be required by specific carriers, manufacturers are better able to work most effectively and efficiently with third-party testing laboratories.
Exploring Qualified NEBS Testing Laboratories
Choosing the right NEBS testing laboratory to work with involves considering a host of issues, from laboratory capabilities and accreditations to staff expertise. Equipment manufacturers might also examine whether a provider is able to outline start dates and availability for project planning well before testing actually begins.
In assessing provider capabilities, manufacturers should:
- be aware that product size and weight limitations might preclude some laboratories from completing certain test profiles.
- make sure the NEBS test facility is ISO 17025 accredited and qualified under any carrier specific laboratory accreditation programs, such as the Verizon ITL program.
- inquire about the training and expertise of testing staff and ensure engineers are actively engaged in industry technical committees, regularly attend industry symposia and are current with any applicable professional certifications.
It’s important to note that a comprehensive, full service laboratory will support NEBS testing with the following:
- Full EMC test facility capable of conducting both immunity and emissions testing
- Environmental chambers to conduct temperature and altitude testing
- Vibration and seismic test facilities
- Full-scale fire facility
- Facilities to support acoustic power measurements
- Various test facilities to support lightning surge and power fault simulations, DC power measurements
- Conditioning chambers to support mixed flowing gas testing and test apparatus to support hygroscopic dust exposure
These laboratories should document and deliver a test report that outlines an overall test strategy and contains individual test methods and results. The test laboratory should also include separate videos of the large-scale fire tests and seismic tests.
In addition to the Telcordia Generic Requirements, a testing laboratory should be familiar with the related American National Standards developed by the Alliance for Telecommunications Industry Solutions (ATIS). These standards, such as ATIS-0600319, Equipment Assemblies – Fire Propagation Risk Assessment, or the ATIS-0600015 series of energy efficiency testing standards are often referenced in the Telcordia GRs or, in some cases, are specifically required by the service provider community.
A full service laboratory should also be able to support testing to international standards for manufacturers that seek compliance for the global marketplace. Examples of these standards include the ETSI 300 019 and 300 386 series of standards dealing with the physical and EMC environments, respectively. No matter the current or future setting of laboratory testing, telecom equipment manufacturers should ensure that their equipment undergoes proper NEBS and customer specific required testing. Viewing this commitment as an important part of product investment, manufacturers should seek out an ITL with the technological tools and expertise to carry out the testing process, including test methods that address any modifications to requirements.
In understanding and achieving NEBS compliance, a manufacturer gains standing as a company whose equipment enhances rather than jeopardizes network integrity and protects the safety of the personnel who operate it. The return on this product investment not only includes reduced design and related costs over the long term, but the advantage of being positioned to make great strides in an evolving worldwide marketplace that presents exciting, new opportunities every day.
UL is a premier global safety science company with more than 100 years of proven history. A pioneer in NEBS testing since 1992, UL operates three full service EMC facilities located throughout North America. Each has a variety of NEBS capabilities and is staffed with highly trained, experienced, and NARTE certified engineers.
© UL LLC 2013. Reprinted with permission.
is currently the North American Wireless & EMC Quality Manager for UL. In 2008, Marotto served as Global NEBS Program Development Manager and was responsible for developing and implementing UL’s NEBS Fastrack Program, which enables international Telecom manufacturers to perform NEBS and telecom related testing in their own laboratories under the witness of UL staff. Prior to that, Marotto was Operations Manager for UL’s EMC and NEBS testing laboratories in Research Triangle Park, N.C. Matt received his bachelor’s degree in electrical engineering from the University of Alabama and is an iNARTE certified product safety engineer.
is UL’s Principal Engineer in the high tech and telecommunications area. He is responsible for the development, implementation and maintenance of various UL Standards and certification programs including UL’s NEBS Mark program. Randy is a member of the National Electrical Code, NFPA 70, Code Making Panel No. 16 that is responsible for Chapter 8 covering communications systems. He is chairman of the TIA TR41.7 Committee on Environmental and Safety Issues and is a member of the ATIS Sustainability in Telecom: Energy and Protection Committee (STEP) in which he chairs the NPP subcommittee on physical protection. Randy received his bachelor of science degree in electrical engineering and his master of science in technology management from Polytechnic University and is an iNARTE certified product safety engineer.