ASTM C150, C595 Type IL, EN 197-1 and TCVN: reading a cement spec when you import

What does each of these standards actually cover?

These names get used as if they were interchangeable. They are not. Each is a different rulebook, and an import quote should say which one it means.

• ASTM C150 covers portland cement. It defines types by use: Type I for general use, Type II where moderate sulfate resistance is wanted, Type III for high early strength, Type IV for low heat of hydration, and Type V for high sulfate resistance, plus air-entraining versions. The cement may contain only portland cement clinker, water or calcium sulfate or both, limestone, processing additions, and, for air-entraining types, an air-entraining addition.
• ASTM C595 covers blended hydraulic cements: portland cement or clinker combined with slag, pozzolan, limestone, or some combination of these. Type IL, portland-limestone cement, is a C595 product. That is why Soku lists it as ASTM C595 and AASHTO M240, not under C150.
• EN 197-1 is the European standard for common cements, titled Composition, specifications and conformity criteria for common cements. Its CEM I is the near-pure portland cement: 95 to 100 percent clinker by mass of main constituents, with the balance minor additional constituents.
• TCVN 6260 is the Vietnamese standard behind PCB40 and PCB50, strength-graded blended cement for general construction. TCVN 7024 is the clinker standard behind CPC 50, traded to the CPC grade and suitable as the input for cement made to ASTM C150 or EN 197-1.

One honest limit. We describe the EN and TCVN standards only to the level we have verified, and we do not reproduce clauses from them here. Read the current edition of any standard your contract depends on, and confirm which edition your specification cites.

Is PCB40 or PCB50 cement the same as ASTM C150 cement?

No. PCB40 and PCB50 are graded under TCVN 6260, Vietnam’s blended cement standard. ASTM C150 is a different document with a closed list of permitted ingredients, and a cement either conforms to a C150 type or it does not. A PCB label tells you the product meets the Vietnamese standard. It does not tell you the product meets any C150 type, and Soku does not sell it as one.

Our documented ASTM conformance today is C150 Type I and Type II, including low-alkali grades. If your specification calls for C150 Type I/II, that is the product we quote. PCB cement is a separate TCVN product for buyers who want it by that name, and the quote should say so. Do not convert a PCB number into a US type by eye.

Why is Type IL made to order, and why does your lab qualify it first?

Type IL is produced to order rather than held in stock, and a minimum parcel applies. C150 itself carries a similar warning: it notes that cement conforming to every type is not carried in stock in some areas, and says to determine availability before specifying anything other than Type I.

Because our documented conformance today is Type I and Type II, we supply Type IL samples for your own laboratory to qualify before any contract. We will not represent a Type IL as qualified for your specification until your lab says it is. Iowa DOT’s archived 2022 materials instruction describes Type IL as a direct replacement for Type I or Type I/II, but other agencies differ, so check your own specification. If Type IL is what your project calls for, say so at the inquiry stage, because it changes the lead time.

What does a mill test report prove?

A mill test report documents the results for a lot of cement against a named standard. Every Soku shipment includes mill test reports documenting conformance, and the product is third-party tested at a VILAS 1601 accredited laboratory. Independent SGS inspection is available at three stages, with the sampling method, laboratory, and acceptance criteria named in the contract.

What a report does not do is replace your acceptance process. Project acceptance is always subject to your engineer’s specification and shipment testing. Public agencies often add their own layer. Iowa DOT’s archived instruction bases approval on certification by an approved source or on source sampling and testing, and it expects mill test reports for the cement shipped and a certification statement on the invoice or bill of lading.

Do AASHTO M 85 and M 240 mean the same thing as ASTM C150 and C595?

For portland cement, effectively yes. The American Cement Association describes AASHTO M 85 and ASTM C150 as harmonized, and a spring 2026 presentation on cementitious material specifications lists them the same way.

For blended cement, be more careful. AASHTO M 240 is the counterpart of ASTM C595, and the American Cement Association pairs them. That same 2026 presentation reports that the two are not currently harmonized, after AASHTO did not approve a new blended-cement type that ASTM did. For a state DOT job, find out whether the specification cites AASHTO M 240 or ASTM C595, and which edition, before you assume a Type IL from one satisfies the other.

How do state DOTs approve a cement source?

For public and DOT work, states qualify cement sources through approved-source lists backed by AASHTO-accredited mill laboratories (ASTM C1222), ASTM C150/C595 conformance documentation, shipment-level certification, and in some states NTPEP data. Several state specifications explicitly admit foreign mills that meet these requirements. Soku USA manages the approved-source application process alongside your team, state by state.

ASTM C1222 is the practice for evaluating laboratories that test hydraulic cement. It sets minimum criteria for a laboratory’s capability to run the chemical and physical tests listed in the cement specifications, including C150 and C595. Iowa DOT’s archived instruction is a useful example of how an agency uses it. It lists approved cement sources and distribution terminals, requires a C1222-compliant, AASHTO-accredited control laboratory at the plant, and says it may accept a source another state has approved if that state agrees to stated terms. Requirements differ by state, so treat it as an illustration.

Why qualify more than one plant from the start?

Cement approval attaches to a specific source, not to a specification. Once your lab has qualified one plant against your aggregates and admixtures, a second plant cannot simply be substituted later to protect a delivery date. It has to go through its own qualification with its own material, and a full vetting cycle can run many months.

So we submit several plants for qualification at the outset. If schedule pressure later forces a source change, the alternate is one your laboratory has already seen. Phuc Loi’s reach across multiple tier-one producers is what makes that possible. Any substitution still depends on your approval and on capacity being available. Iowa DOT’s archived instruction also bars mixing cement from different sources, plants, or types in one storage bin or silo, another reason to settle the source before cargo moves.

What should you send with an inquiry?

A useful inquiry includes:

1. The standard, type, and edition your specification cites, for example ASTM C150 Type I/II or ASTM C595 Type IL, and the AASHTO equivalent if it is a DOT job.
2. Whether the owner or state requires an approved-source listing, and which agency.
3. Whether you need an Environmental Product Declaration, so the order can be routed to a plant that already holds a current one.
4. Volume, destination port, and how you receive: bulk, lined bulk bags, or trade bags.