Aeration Specsmanship in the US Market
Please beware of specsmanship in the diffused aeration market. Ethical salesmen will help Consulting Engineers & End Clients improve specs for the client’s benefit, and not insert poisonous clauses that exist only to eliminate competition and not to help you get a better product or better price! Please read these points carefully as these are three of the most common areas of ‘specsmanship’ we are seeing in 2018.
I. SOTE tests – The best test is an independently certified one, conducted in a facility with calibrated instrumentation, where the tests are conducted in accordance with the ASCE 2006 clean water test standards. Restricting tests by the geographical location of the tank, tank shape or other factors outside of the ASCE requirements provides no benefit to the client. And if there is to be a geographical location restriction, the best location for an SOTE test is a warm climate, where corrections for cold water are not required, because those corrections often overshoot, resulting in artificially high SOTE results.
II. Superior membrane materials like PTFE coated EPDM – If you are specifying a basic material like EPDM as a base bid, what is the point in restricting superior membranes, such as an EPDM membrane with a PTFE coating? If you are allowing an open bid, there is no disadvantage to you as a client to receive a better product. From the manufacturer’s perspective, it may reduce the risk of offering you an extended warranty by providing a superior material, ultimately lowering your costs of acquiring a better aeration system.
III. Diffuser mounting method – It is unlikely that you are specifying the number of threads, the shape or type of thread in the diffuser holder or the torque of those parts, keeping the membrane in place. It’s also unlikely that you are specifying the glued contact area between the diffuser and the PVC lateral pipe. What really matters is the ability of the diffuser to resist pull-out force. If one company uses an interference fit and another company uses a glued connection, does it really matter to the end user so long as the holder to pipe connection works and allows the end user at a later date to easily remove the retaining ring, replace a membrane, and screw the ring back on?
Tips to avoid unethical specsmanship:
*Take control of your own specs to go for a competitive bid that is designed to give you the best product at the best price.
*Ask yourself when you read your spec – is this paragraph for MY/MY CLIENT’s benefit, or for the vendor?
*If you are working with a vendor that you like, ask them to point out the specific benefits of their product, and consider writing an ‘alternate add’ for them or create an option on your bid form for alternates but keep the base bid competitive and open.