Approved Equal & Substitution Review Support
A bid spec names one manufacturer’s pump, tank, or valve. Your quote depends on a different one. Here’s the real comparison data a contractor needs to submit an “or equal” substitution request — and the honest limits of what LibertyCES can and can’t decide for you.
30+ years spec experience. Send James the basis-of-design spec and your proposed alternate — get a real comparison, not a sales pitch.
Request a Spec Review →Almost every construction or capital-project bid specification names a specific manufacturer and model as the “basis of design” — the exact product the spec was written around. Most specs also carry an “or equal” or “approved equal” clause, meaning a genuinely equivalent product from a different manufacturer can be substituted if the contractor proves it out. That proof is where most substitution requests actually fail — not because the alternate is wrong, but because the comparison behind it is thin, generic, or missing the one requirement the spec actually cares about.
LibertyCES Doesn’t Approve Substitutions — the Engineer of Record Does
This has to be stated plainly, because it’s the single most common misunderstanding in this process: no distributor, manufacturer’s rep, or supplier — LibertyCES included — has the authority to “approve” a substitution on a project it did not design. That authority sits with the engineer of record or the owner’s representative, full stop. What LibertyCES actually provides is the real, sourced technical comparison that supports a contractor’s own substitution request — material ratings, pressure and flow envelopes, certifications, and honestly flagged differences — so the person who does have that authority can evaluate it quickly and with confidence, instead of chasing down manufacturer cut sheets themselves.
From Named Basis of Design to a Decided Substitution
The spec names a basis of design
A bid specification names a specific manufacturer and model — the "basis of design" — often written directly from that manufacturer's own cut sheet. Nothing is wrong with this by itself; it's how most specs get written.
A contractor identifies a real alternate
The awarded contractor (or their supplier) identifies a genuinely equivalent product from a different, often already-approved manufacturer — for cost, lead time, or availability reasons — and wants to bid or supply it instead.
A substitution request gets submitted
The contractor submits a formal "or equal" / substitution request to the engineer of record or owner's representative, backed by a side-by-side technical comparison showing the alternate meets or exceeds every requirement in the basis-of-design spec.
The engineer of record decides
Only the engineer of record or the owner can approve a substitution. LibertyCES is not the approving authority and never claims to be — our role is providing the real comparison data and documentation that makes the request easy to evaluate, not making the call.
Requirement by Requirement, Not Brand by Brand
A useful substitution comparison never argues that one manufacturer is generally better than another — it walks through the specific requirements the basis-of-design spec actually states (flow range, pressure rating, wetted material chemical compatibility, certifications, a named functional feature like tube failure detection or a vented ball) and shows, requirement by requirement, whether the proposed alternate is the same, meaningfully different, or simply unverified against a given data point. Real technical differences don’t automatically disqualify an alternate — they just need to be disclosed, not hidden, so the engineer of record can weigh them.
The three comparisons below use only real, already-sourced vendor data captured for LibertyCES’s own quoting and engineering work — not invented specs or generic marketing claims.
Approved-Equal Comparisons by Category
Chemical Metering Pumps →
Blue-White FLEXFLO/CHEM-FEED vs. ProMinent DULCOFLEX/Sigma vs. Graco G-Chem — peristaltic, diaphragm, and plunger technology compared for sodium hypochlorite and general chemical dosing service.
Chemical Storage Tanks →
Poly Processing (XLPE) vs. Snyder Industries (HDLPE) vs. Assmann (XLPE/LLDPE) — including the real, unresolved cross-vendor resin disagreement for sodium hypochlorite storage.
Chemical Feed Ball Valves →
Hayward TBH-Z vs. Asahi/America Type-21/21a — vented-ball design for sodium hypochlorite off-gassing service, compared feature by feature.
Approved Equal & Substitution Request FAQ
Can LibertyCES approve a substitution or "approved equal" request?
No. Only the engineer of record or the project owner's representative can approve a substitution — that authority belongs to whoever stamped or is legally responsible for the design, not to a distributor or manufacturer's rep. LibertyCES is not the engineer of record on any project it did not design, and never claims approval authority it doesn't have. What we actually do is prepare the real, side-by-side technical comparison — material ratings, pressure/flow envelopes, certifications, documented differences — that supports the contractor's own substitution request to the people who do have that authority.
What is the difference between "approved equal," "or equal," and a "substitution request"?
They describe the same real process from different angles. "Or equal" or "approved equal" is the specification language itself — a clause in the bid documents saying a named product OR a genuine equal will be accepted. A "substitution request" (sometimes called a submittal or a substitution submittal) is the actual document the contractor files, showing how the proposed alternate meets every requirement of the named basis-of-design product. There is no separate legal category called an "approved equal product" until the engineer of record has actually reviewed and approved that specific substitution request on that specific project.
What does a real substitution request need to include?
At minimum: the named basis-of-design manufacturer and model, the proposed alternate manufacturer and model, and a requirement-by-requirement comparison — flow/pressure/capacity range, wetted materials and chemical-compatibility ratings, certifications (NSF/ANSI 61, API, ASTM), connection type and size, and any functional feature the spec calls out by name (like tube failure detection on a metering pump or a vented ball on a sodium hypochlorite valve). Vague claims of "equivalent performance" without the underlying data are the most common reason a substitution request gets rejected or delayed.
Does a genuine equal always use the exact same technology as the basis of design?
Not necessarily, and that is exactly where a substitution request needs the most scrutiny, not the least. A peristaltic metering pump and a diaphragm metering pump can both meet the same dosage requirement in GPD, but they achieve it through different mechanisms with different failure modes, maintenance profiles, and material-compatibility considerations. LibertyCES's comparison pages call out these mechanism-level differences explicitly rather than only matching headline flow numbers — a real technical difference doesn't automatically disqualify an alternate, but it does need to be understood and disclosed, not glossed over.
What happens when two manufacturers genuinely disagree on the right material or design for a chemical?
It happens more often than most specs assume, and sodium hypochlorite storage is a real example: Poly Processing and Assmann both recommend cross-linked polyethylene (XLPE) tanks, while Snyder Industries' own accelerated-aging test data shows high-density linear polyethylene (HDLPE) outperforming XLPE for this exact chemical. LibertyCES presents both documented positions in that comparison rather than picking a side — an engineer of record evaluating a real substitution request deserves to see a genuine, sourced disagreement as a disagreement, not a manufactured consensus.
Working a substitution request right now?
Send James the basis-of-design spec sheet and the manufacturer/model you want to propose instead — I’ll build the real requirement-by-requirement comparison your submittal needs, sourced from actual vendor data, not a generic chart.
Ready to buy or need a fast answer? Call, text, or email James directly — (559) 395-5500 · [email protected].