Selected Answers

From Michael Halliwell of Thurber Engineering Ltd. on July 29, 2019:
When it comes to the "or equivalent" with coatings ...read more When it comes to the "or equivalent" with coatings, I'm pretty sure there are a lot more things to look at. For the specs where we've used the terminology for a liner, we've included the key parameters (tensile strength, elongation, thickness) that need to be met for the specified product along with who would approve an alternate product. In our case, the manufacturers produce very similar products, so it is simple,.but for a coating, I'd say Frank is on the right track--provide a choice or short list of what will work, an approved products list.

From William Gusnard of Southern Company Services on July 29, 2019:
When I write a spec, I recommend a coating system ...read more When I write a spec, I recommend a coating system (or approved equal). The 'or equal' must be approved by me and the 'or equal' must have all supporting documents submitted to me (not me having to find them) before I will approve the product.

From Frank Rea of Consulex on July 24, 2019:
The answer should be provided in the specification ...read more The answer should be provided in the specification, but this is a common omission. The specification should provide the criteria for equivalency and identify who makes the final decision. Specifying "or equivalent" is typically seen as a simple way ti avoid sole-sourcing. However, in fact, it creates a significant amount of administrative time and cost if the Contractor submits a material other than the one provided as the basis of design. The decision maker must review and compare a significant amount of information, e.g., chemical properties, physical properties and test data. I feel providing three system choices in the specification would be preferable. Moreover, if an Owner regularly puts out the same type of project for bid, i.e., same application, developing an approved products list would be the best option.