oSIST prEN ISO 13503-5:2026

• 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
• Public Enquiry End Date: 19-Jul-2026
• ICS: 75.100 - Lubricants, industrial oils and related products
• ICS: 75.180.10 - Exploratory, drilling and extraction equipment
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 22-May-2026
• Due Date: 09-Oct-2026
• Completion Date: 22-Jul-2026
• Ref Project: prEN ISO 13503-5 - Oil and gas industries including lower carbon energy - Completion fluids and materials - Part 5: Measuring conductivity of proppants (ISO/DIS 13503-5:2026)

• Revises: SIST EN ISO 13503-5:2007 - 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

oSIST prEN ISO 13503-5:2026 is a draft standard for the oil and gas industries, published by SIST and aligned with ISO/DIS 13503-5:2026. It specifies test procedures for measuring the conductivity of proppants used in hydraulic fracturing and gravel packing, and it supplements API RP 19D, 2nd edition (2021). In practice, it is the document to use when you need a consistent laboratory method for comparing proppant behavior under load.

What does oSIST prEN ISO 13503-5:2026 specify?

oSIST prEN ISO 13503-5:2026 specifies standard testing procedures for evaluating proppants used in hydraulic fracturing and gravel packing operations. The document is about consistent methodology for testing, not about deriving absolute proppant pack conductivity values under downhole reservoir conditions.

The standard treats “proppants” broadly. In this part, that term covers sand, ceramic media, resin-coated proppants, gravel packing media, and other materials used for these operations.

The document is organized into:

• Clause 1 - Scope
• Clause 2 - Normative references
• Clause 3 - Supplements to API RP 19D, 2nd edition (2021)
  • 3.1 General requirements
  • 3.2 Procedure for Loading the Cell(s)
    • 3.2.1 Loading Dry Proppant into the Cell(s)
    • 3.2.2 Loading Cell(s) in the Load Frame
  • 3.3 Acquiring Data
• Bibliography

What are the key requirements of oSIST prEN ISO 13503-5:2026?

oSIST prEN ISO 13503-5:2026 is mainly a set of exceptions and additions to API RP 19D, 2nd edition (2021). If you already run that test, this document tells you which steps stay the same and which steps change.

Core test basis

Clause 3.1 says the requirements of API RP 19D apply, except for the provisions identified in 9.7 to 10.3 and Annex C, Figure C.7. In practice, that means the ISO document does not replace the whole test method - it modifies specific loading and data-acquisition steps.

Loading the dry proppant

Clause 3.2.1 replaces the original levelling step with a new levelling device shown in Figure 1. The proppant is to be levelled uniformly in the cell, and the document notes that vibration or tamping shall not be used because they can segregate the material. For a test lab, this matters because the starting pack condition affects the measured conductivity.

Loading the cells in the load frame

Clause 3.2.2 changes the pressurization sequence used when loading the cell(s) in the load frame. The pressure is raised 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 operator must control the ramp rate and the back-pressure, not just the final stress value.

Data acquisition and holding times

Clause 3.3 changes how conductivity data are collected. After the initial absolute stress of 6.9 MPa, the sample is held for 12 h to 24 h at the required temperature, with back-pressure maintained between 2.1 MPa and 3.5 MPa. The later stress steps increase in 13.80 MPa increments, and every ramp uses the same 100 kPa/min rate.

Extra stress points during pressurization

Clause 3.3 also adds stress points during pressurization, each held for 10 minutes to measure conductivity. These points are there to show the conductivity trend and reduce experimental error. For users, this means the data set is not just a few end points - it includes intermediate readings during the ramp.

Longer final hold

Clause 3.3 states that the stress on the proppant pack shall be held for 50 h ± 2 h after the initial stress period. Holds shorter than 48 h are not treated as single point conductivity. In practice, this affects how results are reported and compared between tests.

What terms does oSIST prEN ISO 13503-5:2026 define?

• Proppants - The materials placed in the fracture or gravel pack to help maintain flow paths, including sand, ceramic media, resin-coated proppants, gravel packing media, and similar materials.
• Hydraulic fracturing - The well intervention process named in the scope as one of the intended uses for the proppants being tested.
• Gravel packing - The other application named in the scope where these proppants are used and evaluated.
• Conductivity - The measured property of the proppant pack that the test method is designed to determine.
• Closure stress - The compressive stress applied to the proppant pack during loading and conductivity testing.
• Back-pressure - The pressure maintained during the test while stress is being applied or held, which the method explicitly uses and accounts for.
• Load frame - The apparatus used to load the cell(s) under pressure in the test procedure.

Who uses oSIST prEN ISO 13503-5:2026?

oSIST prEN ISO 13503-5:2026 is used by people who test, compare, or specify proppants for hydraulic fracturing and gravel packing. That includes laboratory staff, completion engineers, proppant suppliers, and quality or procurement teams that need a common test method.

It is relevant in the oil and gas industries, including lower carbon energy, and in the broader area of completion fluids and materials. The document is also useful when a buyer or user needs to judge whether a proppant test result was generated using the same loading and stress history as other reported results.

What changed in oSIST prEN ISO 13503-5:2026 from the previous edition?

This second edition cancels and replaces ISO 13503-5:2006, and it incorporates the amendment to that edition. The foreword says the update brings the document into line with API RP 19D, 2nd edition (2021), and adds supplementary content.

The stated main changes are:

• a new levelling device
• a reduced stress increase rate of 100 kPa/min ± 10 kPa/min
• additional stress points during pressurization

Which standards are used with oSIST prEN ISO 13503-5:2026?

The normative reference named in the document is:

• API RP 19D, 2nd edition (2021), Measuring Conductivity of Proppants - this is the base method that oSIST prEN ISO 13503-5:2026 supplements, with only the exceptions stated in the ISO document.

What does the oSIST prEN ISO 13503-5:2026 document contain?

The document contains the scope, one normative reference, and a short set of supplementary procedures built around API RP 19D. Its technical content is concentrated in Clause 3, where it specifies the levelling device, the cell-loading sequence, the pressure ramp rates, the stress hold times, and the added stress points used during conductivity measurement.

It also includes Figure 1 showing the levelling device, and a bibliography with two cited SPE papers on proppant conductivity. For users, the practical value is in the test setup details and timing rules that control how conductivity results are generated and compared.

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
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 —
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.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2026
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
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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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