prEN ISO 13503-5

• Abstract:

  ISO 13503-5:2006 provides standard testing procedures for evaluating proppants used in hydraulic fracturing and gravel packing operations. ISO 13503-5:2006 provides a consistent methodology for testing performed on hydraulic fracturing and/or gravel packing proppants. The "proppants" mentioned henceforth in this part of ISO 13503-5:2006 refer to sand, ceramic media, resin-coated proppants, gravel packing media, and other materials used for hydraulic fracturing and gravel-packing operations.; ISO 13503-5:2006 is not applicable for use in obtaining absolute values of proppant pack conductivities under downhole reservoir conditions.

• Status: Not Published
• Publication Date: 03-Mar-2027
• ICS: 75.180.10 - Exploratory, drilling and extraction equipment
• Technical Committee: CEN/TC 12 - Materials, equipment and offshore structures for petroleum and natural gas industries
• Drafting Committee: ISO/TC 67 - ISO/TC 67
• Current Stage: 4599 - Dispatch of FV draft to CMC - Finalization for Vote
• Start Date: 06-Aug-2026
• Completion Date: 06-Aug-2026
• Ref Project: oSIST prEN ISO 13503-5:2026 - Oil and gas industries including lower carbon energy - Completion fluids and materials - Part 5: Measuring conductivity of proppants (ISO/DIS 13503-5:2026)

• Revises: EN ISO 13503-5:2006 - Petroleum and natural gas industries - Completion fluids and materials - Part 5: Procedures for measuring the long-term conductivity of proppants (ISO 13503-5:2006)
• Effective Date: 18-Feb-2026

prEN ISO 13503-5 is a CEN/ISO draft standard for measuring the conductivity of proppants used in hydraulic fracturing and gravel packing. It supplements API RP 19D, 2nd edition (2021), and gives the test procedure, loading steps and data-acquisition rules used by laboratories, proppant suppliers and completion engineers to compare sand, ceramic media, resin-coated proppants and other gravel-packing media.

What does prEN ISO 13503-5 specify?

prEN ISO 13503-5 specifies standard testing procedures for evaluating proppants in hydraulic fracturing and gravel packing operations. It is intended to give a consistent method for testing these materials, not to produce absolute proppant pack conductivity values under downhole reservoir conditions.

The document is organized into a short set of clauses:

• Clause 1 covers the scope.
• Clause 2 lists the normative reference.
• Clause 3 contains the supplements to API RP 19D, 2nd edition (2021).
• Clause 3 is split into general requirements, loading the cell(s), and acquiring data.
• A bibliography closes the document.

What are the key requirements of prEN ISO 13503-5?

prEN ISO 13503-5 works as a supplement to API RP 19D, so the base test method comes from API RP 19D and this document states where the procedure is changed or clarified. In practice, users need both documents together when setting up and running the conductivity test.

Apply API RP 19D, with the stated exceptions

Clause 3.1 says the requirements of API RP 19D, 2nd edition (2021), apply except for the provisions named in this document. The practical effect is that laboratories follow the established API method, then substitute the updated steps in prEN ISO 13503-5 where required.

Use the levelling device when loading dry proppant

Clause 3.2.1 replaces the original levelling arrangement with a new levelling device shown in Figure 1. The proppant is to be levelled after filling, and not packed by vibration or tamping. That matters because segregation or packing changes the test bed and can distort conductivity results.

Load the cell(s) with the specified pressure steps

Clause 3.2.2 replaces parts of the API loading sequence. The cell(s) are pressurised from 350 kPa to 3.5 MPa, then to 6.9 MPa, at about 100 kPa/min, and the 6.9 MPa closure stress is adjusted to account for back-pressure between 2.1 MPa and 3.5 MPa. In practice, the test rig operator must control pressurisation rate and back-pressure carefully so the applied stress is the intended stress on the proppant pack.

Follow the stated stress progression during data acquisition

Clause 3.3 changes the data-acquisition stage. After the initial 6.9 MPa stress, the stress is increased in 13.80 MPa increments, again at about 100 kPa/min. This gives a defined stress history, which is important when comparing results from different proppants or different laboratories.

Hold the initial stress for the required time at temperature

Clause 3.3 also requires the initial absolute stress of 6.9 MPa to be maintained for 12 h to 24 h at the required temperature, while back-pressure is kept between 2.1 MPa and 3.5 MPa. The text also states that the stress is later held for 50 h ± 2 h, and that holds shorter than 48 h do not count as single point conductivity. This is what makes the result usable for controlled comparison rather than a short screening check.

Record intermediate stress points during pressurisation

Clause 3.3 calls for several stress points during pressurisation, each held for 10 minutes to measure conductivity. In practice, these intermediate points help show the conductivity trend and reduce the risk of missing a change in behaviour.

What terms does prEN ISO 13503-5 define?

• Proppants - The materials placed in the fracture or packed zone to help keep flow paths open; in this document they include sand, ceramic media, resin-coated proppants, gravel packing media and similar materials.
• Hydraulic fracturing - A completion operation in which the proppant conductivity test is used to evaluate the materials placed in the created fracture.
• Gravel packing - A completion method that uses proppant-like media, and for which this document provides the same conductivity test approach.
• Closure stress - The compressive stress applied to the proppant pack during the test.
• Back-pressure - The pressure maintained while the cell is loaded, and one that must be taken into account when determining the applied stress.
• Load frame - The equipment used to pressurise the cell(s) during the conductivity test.
• Single point conductivity - The conductivity value associated with a stress hold, where the document requires a defined hold time before the result is treated as such.

Who uses prEN ISO 13503-5?

prEN ISO 13503-5 is used by test laboratories, proppant manufacturers, completion fluids and materials suppliers, and oil and gas operators that need comparable conductivity data. It is also relevant to quality managers and buyers who specify acceptance tests for proppants and need a common method for supplier comparison, batch qualification or product development.

What changed in prEN ISO 13503-5 from the previous edition?

prEN ISO 13503-5 is the second edition and it cancels and replaces ISO 13503-5:2006, including Amendment 1. The foreword states that the document has been technically revised and that the main changes are:

• a new levelling device;
• a reduced stress-increase rate of 100 kPa/min ± 10 kPa/min;
• additional stress points during the pressurisation process;
• alignment with API RP 19D, 2nd edition (2021).

Which standards are used with prEN ISO 13503-5?

The normative reference named in the document is API RP 19D, 2nd edition (2021), Measuring Conductivity of Proppants. prEN ISO 13503-5 uses API RP 19D as the base procedure and then states the exceptions and additions needed for this edition.

What does the prEN ISO 13503-5 document contain?

The document contains the scope, one normative reference, and a technical Clause 3 that sets out the supplements to API RP 19D. It also includes Figure 1, which shows the levelling device used when loading dry proppant into the cell(s).

Clause 3 gives the practical test steps for loading the cell(s) and acquiring conductivity data. The bibliography lists two technical references on proppant-pack conductivity, which support further study and comparison of test practice.

SLOVENSKI STANDARD
01-julij-2026
Naftna in plinska industrija, vključno z nizkoogljično energijo - Tekočine in
materiali za zaključna dela - 5. del: Merjenje prevodnosti podpornih materialov
(ISO/DIS 13503-5:2026)
Oil and gas industries including lower carbon energy - Completion fluids and materials -
Part 5: Measuring conductivity of proppants (ISO/DIS 13503-5:2026)
Öl- und Gasindustrie einschließlich kohlenstoffarmer Energieträger -
Komplettierungsflüssigkeiten und Materialien - Teil 5: Messung der Leitfähigkeit von
Stützmaterialien (ISO/DIS 13503-5:2026)
Titre manque — Partie 5: Titre manque
Ta slovenski standard je istoveten z: prEN ISO 13503-5
ICS:
75.100 Maziva Lubricants, industrial oils and
related products
75.180.10 Oprema za raziskovanje, Exploratory, drilling and
vrtanje in odkopavanje extraction equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
International
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ISO/DIS 13503-5
ISO/TC 67/SC 3
Oil and gas industries including
Secretariat: UNI
lower carbon energy — Completion
Voting begins on:
fluids and materials —
2026-05-05
Part 5:
Voting terminates on:
2026-07-28
Measuring conductivity of
proppants
ICS: 75.100; 75.180.10
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Reference number
ISO/DIS 13503-5:2026(en)
DRAFT
ISO/DIS 13503-5:2026(en)
International
Standard
ISO/DIS 13503-5
ISO/TC 67/SC 3
Oil and gas industries including
Secretariat: UNI
lower carbon energy — Completion
Voting begins on:
fluids and materials —
Part 5:
Voting terminates on:
Measuring conductivity of
proppants
ICS: 75.100; 75.180.10
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
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BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2026
TECHNOLOGICAL, COMMERCIAL AND
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Published in Switzerland Reference number
ISO/DIS 13503-5:2026(en)
ii
ISO/DIS 13503-5:2026(en)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Supplements to API RP 19D, 2nd edition (2021) . 1
3.1 General requirements .1
3.2 Procedure for Loading the Cell(s) .1
3.2.1 Loading Dry Proppant into the Cell(s) .1
3.2.2 Loading Cell(s) in the Load Frame .3
3.3 Acquiring Data .3
Bibliography . 4

iii
ISO/DIS 13503-5:2026(en)
Foreword
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