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Thursday, October 29, 2009

Listed product - UL Mark

Advantages of Listing over Type Testing

LISTING is a process of certifying a product as it migrates through defined stages of

Engineering Planning

Intermediate Review

Constructional Assessment

Testing, Documentation

Final Review

Factory Inspections and labeling

Continued unannounced manufacturing surveillance

Type Testing involves Testing a representative sample / construction of a certain product at a not necessarily ILAC accredited Third party laboratory to a specified product standard, often only under conditions of Witness by the Laboratory Engineer and Issue of Report in a standard / custom format depending on full or partial testing undertaken
LISTED products invariability conform to all relevant clauses, both constructional and testing requirements of the standard applicable for the product. They internally refer to other applicable standards and the application of each referenced standard is defined in the category being evaluatedType tested products do not clearly specify if the product has complied with all testing clauses applicable. Typically constructional requirements are not verified. Also, as there is no defined program for a certain category, clear information on all referenced standards is typically is not available when evaluating the end product
A LISTED product goes through a multiple Review process to check the project engineer’s evaluation. The Project Engineer necessarily has to be different from the Project Reviewers allowing independency in interpretation and outputGenerally there are no review mechanisms in a type testing report which are updated by lab personnel themselves
The LISTING Categories refer to Product Standards that are ‘Application Specific’ and are investigated to its requirements that address specified hazards in the installed environmentThe Performance requirements of the type tested product standard are ‘Product specific’ and not holistically applied
Safety is explicitly the focus of the evaluation, through Testing and component selection to address performance requirements and many other hazards like FIRE SAFETY, Electric Shock Prevention, Safety in Product Failure etc.Type testing is done typically to verify performance aspects only
A LISTED product has to go through continued compliance via follow up service inspections happening periodically at EACH of the locations where the product is manufactured. This ensures the product submitted for testing is the same as that the one being routinely mass manufacturedProduct goes through one time testing and no regular inspections/tests to ensure continued compliance and hence can affect product reliability
The critical components used in the product have to be from LISTED / Recognized sources to the relevant component standards. The LISTED components used in the product also undergo similar follow up inspections at their factories, ensuring traceability and continued complianceComponent qualification for use has to be reverified each time for minimum requirements on basis of end product manufacturer claims. Traceability is not possible nor ensured
Sampling (of products for a LISTING evaluation) is done scientifically by selecting representative samples from all possible configurationsNo scientific guidelines for sample selection, and typically the best available sample/(s) are tested
Random field inspections are typically carried out from products in the field, and tested. This is a part of the surveillance check. Any product noncompliance can lead to withdrawal of LISTINGNot Applicable
LISTED products have to meet categorized specified labeling requirements to the standards, which ensure quick traceability of product as well is a measure to check counterfeit productsNo mechanism to check for counterfeit products, since there are only recommendations on markings and labeling
LISTING program offers added benefit of continuously verifying installation aspects such as grounding, bonding etc through Follow up Inspection when controlled in the Inspection reportsOnly Recommendations as above
LISTING ensures reliability of test data as only data generated from ILAC accredited Labs to ISO 17025 are acceptable and all equipment calibration needs to be updated and necessarily endorsed directly by an ILAC approved calibration authorityUnless explicitly called for, often non ILAC approved results are basis of claims
A LISTED product appears in the online certifications directory and sourcing of both components and end products becomes easy, saving significantly on procurement costs and delaysNo listing in any database, and hence vendor selection and procurement becomes an issue
LISTING is withdrawn from Online Database if not in line with certification requirements and online updation is REAL-TIME and is a fool proof method of verifying validity of manufacturer claims. This can also save on expensive retesting by buyers to cross check claimsNot Applicable
LISTING Databases online provide easily searchable component selection interfaces e.g. To select Certified Plastics by Grade & Flammability ratings
Back up Customer support is available by easy reference to LISTED File Numbers
Any Product upgrades and modifications have to be reported and are suitably recertified to retain validity of LISTINGType Test certificates are typically not upgraded to reflect Incremental changes made to the product even if the underlying standard calls for the same

|Fire Safety| Power | Energy | HVAC&R | Lighting | IT & Communications | Security | Water |

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