ASTM C511-21

Standard Specification for Mixing Rooms, Moist Cabinets, Moist Rooms, and Water Storage Tanks Used in the Testing of Hydraulic Cements and Concretes

ABSTRACT
This specification includes the requirements for mixing rooms where paste and mortar specimens are prepared and for moist cabinets, moist rooms, and water storage tanks where paste, mortar, and concrete specimens are stored; intended for use in the testing of hydraulic cements and concretes. The system shall be equipped with a temperature recorder and a reference temperature measuring device that are to be placed practically near to each other. The air and mixing water temperatures and the relative humidity in the cement mixing room shall be maintained at specific values. Moist cabinets and moist rooms shall be constructed of durable materials with tight-fitting doors or windows for all openings. Air in moist cabinet or moist room shall be saturated with moisture in order to provide specified storage conditions and air temperature shall be controlled with provisions made for heating, cooling, or both. The specified relative humidity in these systems shall be maintained by the use of one or more fog sprays, water sprays, or curtains of water on the inner walls. Water storage tanks shall be constructed of non-corroding materials with provisions for automatic control of water temperature. The water in a storage tank shall be saturated with calcium hydroxide to prevent leaching.
SCOPE
1.1 This specification includes requirements for mixing rooms where paste and mortar specimens are prepared; and for moist cabinets, moist rooms, and water storage tanks where paste, mortar, and concrete specimens are stored.  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. Values in SI units shall be obtained by measurement in SI units or by appropriate conversion, using the Rules for Conversion and rounding given in Standard IEEE/ASTM SI 10, of measurements made in other units.  
1.3 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of this standard.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 30-Nov-2021
• ICS: 91.100.10 - Cement. Gypsum. Lime. Mortar
• ICS: 91.100.30 - Concrete and concrete products
• Technical Committee: C01 - Cement
• Drafting Committee: C01.95 - Coordination of Standards

Relations

• Refers: ASTM C219-24 - Standard Terminology Relating to Hydraulic and Other Inorganic Cements
• Effective Date: 01-Apr-2024
• Refers: ASTM C51-23 - Standard Terminology Relating to Lime and Limestone (as Used by the Industry)
• Effective Date: 01-Oct-2023
• Refers: ASTM C219-20a - Standard Terminology Relating to Hydraulic and Other Inorganic Cements
• Effective Date: 01-Aug-2020
• Refers: ASTM C219-20 - Standard Terminology Relating to Hydraulic and Other Inorganic Cements
• Effective Date: 01-Apr-2020
• Refers: ASTM C125-19a - Standard Terminology Relating to Concrete and Concrete Aggregates
• Effective Date: 15-Dec-2019
• Refers: ASTM C219-19a - Standard Terminology Relating to Hydraulic and Other Inorganic Cements
• Effective Date: 15-Nov-2019
• Refers: ASTM C219-19 - Standard Terminology Relating to Hydraulic Cement
• Effective Date: 01-Jun-2019
• Refers: ASTM C125-19 - Standard Terminology Relating to Concrete and Concrete Aggregates
• Effective Date: 01-Jan-2019
• Refers: ASTM C51-18 - Standard Terminology Relating to Lime and Limestone (as used by the Industry)
• Effective Date: 01-Dec-2018
• Refers: ASTM C125-18b - Standard Terminology Relating to Concrete and Concrete Aggregates
• Effective Date: 01-Oct-2018
• Refers: ASTM C125-18a - Standard Terminology Relating to Concrete and Concrete Aggregates
• Effective Date: 01-Jul-2018
• Refers: ASTM C125-18 - Standard Terminology Relating to Concrete and Concrete Aggregates
• Effective Date: 01-Jan-2018
• Refers: ASTM C125-16 - Standard Terminology Relating to Concrete and Concrete Aggregates
• Effective Date: 15-Dec-2016
• Refers: ASTM C125-15b - Standard Terminology Relating to Concrete and Concrete Aggregates
• Effective Date: 15-Dec-2015
• Refers: ASTM C125-15a - Standard Terminology Relating to Concrete and Concrete Aggregates
• Effective Date: 01-Jul-2015

Overview

ASTM C511-21: Standard Specification for Mixing Rooms, Moist Cabinets, Moist Rooms, and Water Storage Tanks Used in the Testing of Hydraulic Cements and Concretes provides comprehensive requirements for facilities and equipment used in the preparation and storage of test specimens for hydraulic cement and concrete. By defining strict environmental controls and construction requirements for mixing rooms, moist cabinets, moist rooms, and water storage tanks, the standard helps ensure the reliability and consistency of tests conducted on cementitious materials. This specification is widely referenced in cement and concrete laboratories to guarantee precision and reproducibility in strength, setting, and durability testing.

Key Topics

• Environmental Controls: Detailed specifications for maintaining air and water temperatures, as well as relative humidity, are provided to ensure consistent curing and mixing environments.
  • Cement mixing room: Air temperature and humidity must meet defined thresholds.
  • Mixing water: Temperature must be maintained for accuracy.
• Construction Materials: Requirements for the durability and construction of moist cabinets, moist rooms, and water storage tanks, focusing on tight-fitting doors, insulation, and non-corroding materials.
• Monitoring and Verification:
  • Use of temperature recorders and reference temperature measuring devices to regularly verify environmental conditions.
  • Documentation practices to ensure continuous compliance.
• Humidity and Moisture Control: Methods for saturating the air in moist environments using fog sprays, water curtains, or other systems, with procedures for checking specimen surface conditions.
• Water Storage and Saturation: Specifications for maintaining lime-saturated water in tanks to prevent deleterious leaching from test specimens.

Applications

ASTM C511-21 is essential for any laboratory or facility performing quality control, research, or compliance testing involving hydraulic cements and concretes. Its practical applications include:

• Laboratory Preparation: Ensuring that paste and mortar specimens are mixed under standardized temperature and humidity conditions prevents variability in test results.
• Specimen Curing and Storage: Defines the required atmosphere (temperature, humidity) and storage solutions (moist cabinets, rooms, and tanks) for specimens, which directly impacts test outcome validity.
• Long-Term Quality Assurance: By mandating the use of temperature recorders and periodic verifications, the standard supports ongoing compliance and traceability for laboratory operations.
• Industry Compliance: Following ASTM C511-21 supports adherence to building codes and construction quality programs that require standardized test conditions for cementitious materials.
• Product Development and Research: Used in academic and industrial research settings to ensure reproducibility and international comparability of test data.

Related Standards

ASTM C511-21 references and complements several other important standards in the field of cement and concrete testing, including:

• ASTM C51 - Terminology Relating to Lime and Limestone
• ASTM C125 - Terminology Relating to Concrete and Concrete Aggregates
• ASTM C219 - Terminology Relating to Hydraulic and Other Inorganic Cements
• ASTM E77 - Test Method for Inspection and Verification of Thermometers
• IEEE/ASTM SI 10 - Standard for Use of the International System of Units (SI)

These related standards ensure a common technical language and consistent measurement practices in cement and concrete laboratories.

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Keywords: ASTM C511-21, cement testing, concrete testing, mixing room specification, moist cabinet, moist room, water storage tank, hydraulic cements, laboratory standards, environmental controls, curing conditions, humidity control, lime saturated water, quality assurance.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: C511 −21
Standard Specification for
Mixing Rooms, Moist Cabinets, Moist Rooms, and Water
Storage Tanks Used in the Testing of Hydraulic Cements
and Concretes
This standard is issued under the fixed designation C511; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope* E77 Test Method for Inspection and Verification of Ther-
mometers
1.1 This specification includes requirements for mixing
C125 Terminology Relating to Concrete and Concrete Ag-
rooms where paste and mortar specimens are prepared; and for
gregates
moist cabinets, moist rooms, and water storage tanks where
C219 Terminology Relating to Hydraulic and Other Inor-
paste, mortar, and concrete specimens are stored.
ganic Cements
1.2 The values stated in SI units are to be regarded as
IEEE/ASTM SI 10 Standard for Use of the International
standard. No other units of measurement are included in this
System of Units (SI): The Modern Metric System
standard. Values in SI units shall be obtained by measurement
in SI units or by appropriate conversion, using the Rules for
3. Terminology
Conversion and rounding given in Standard IEEE/ASTM SI
3.1 Definitions:
10, of measurements made in other units.
3.1.1 RefertoTerminologyC125andTerminologyC219for
1.3 The text of this standard references notes and footnotes
definitions of terms used in this test method.
which provide explanatory material. These notes and footnotes
3.2 Definitions of Terms Specific to This Standard:
(excluding those in tables and figures) shall not be considered
3.2.1 mixing room, n—a room with controlled temperature
as requirements of this standard.
and relative humidity where cement paste and mortar speci-
mens are prepared.
1.4 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
3.2.2 moist cabinet, n—a compartmented storage facility of
responsibility of the user of this standard to establish appro-
moderate dimensions with controlled temperature and relative
priate safety, health, and environmental practices and deter-
humidity.
mine the applicability of regulatory limitations prior to use.
3.2.3 moist room, n—a “walk-in” storage facility with
1.5 This international standard was developed in accor-
controlled temperature and relative humidity, commonly called
dance with internationally recognized principles on standard-
a fog room when the prescribed relative humidity is achieved
ization established in the Decision on Principles for the
by the atomization of water.
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
4. Requirements for Cement Mixing Rooms
Barriers to Trade (TBT) Committee.
4.1 The temperature of the air in the vicinity of the mixing
slab, molds, and base plates shall be maintained at 23.0 6
2. Referenced Documents
2 4.0 °C and at a relative humidity of not less than 50 %.
2.1 ASTM Standards:
4.2 The temperature of the mixing water used to prepare
C51 Terminology Relating to Lime and Limestone (as Used
by the Industry) cement paste and mortar specimens shall be 23.0 6 2.0 °C.
5. Temperature Measuring Devices
This specification is under the jurisdiction of ASTM Committee C01 on
Cement and is the direct responsibility of Subcommittee C01.95 on Coordination of
5.1 Reference Temperature Measuring Device—used to
Standards.
verify the temperature recorder, must be accurate and readable
Current edition approved Dec. 1, 2021. Published December 2021. Originally
to 0.5 ºC. A copy of the certificate or report which verifies the
approved in 1968. Last previous edition approved in 2019 as C511 – 19. DOI:
10.1520/C0511-21.
accuracy shall be available in the laboratory.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
NOTE 1—The ice-point method described in Test Method E77 may be
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on used to ensure that no damage to the reference thermometer has occurred
the ASTM website. during shipping.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C511 − 21
5.2 Temperature Recorder—shall record temperatures every 6.1.1.2 Thermostatically control the space surrounding the
15 min or less and shall be accurate and readable to 1 ºC. The moist cabinet or moist room and manually control the tempera-
data fromthe recorder shall be evaluated at a minimumof once ture within the moist cabinet or moist room.
each week. A record of this evaluation documenting the date 6.1.2 In either of the preceding cases, the laboratory shall
checked, a confirmation that the data is within the required demonstrate the ability of the controls to maintain the required
temperature range, and the name of the individual performing temperature in the moist cabinet or moist room over an
this evaluation shall be maintained in the laboratory. (Note 2) extended period of time. Data from the temperature recorder
that indicates that the temperatures are within the temperature
NOTE 2—This requirement may be satisfied by an initialed and dated
limits specified in 6.1 shall be required as evidence of this
temperature recorder chart. Brief changes in the temperature due to door
ability.
openings should be ignored.
6.2 Moist Cabinets—Amoist cabinet shall be constructed of
5.2.1 The temperature recorder shall be verified at least
durable materials and the doors shall be tight-fitting. The
every six months or whenever there is a question of accuracy.
specified relative humidity shall be maintained by the use of
5.2.1.1 For moist cabinets and rooms, position the reference
one or more fog sprays, water sprays, or curtains of water on
temperature measuring device in a readable position in air as
the inner walls that are so directed that the discharge will
near as practical to the temperature recorder probe. Keep the
collect in a pool at or near the bottom of the moist storage
door closed for at least 5 min prior to taking readings. Record
section.
the temperature readings of both the temperature recorder and
6.3 Moist Rooms:
the reference temperature measuring device. When taking
6.3.1 General—The walls of a moist room shall be con-
these readings, the reference temperature measuring device
structed of durable materials, and all openings shall be pro-
shallremaininthemoistcabinetorroomandreadimmediately
vided with tight-fitting doors or windows (Note 3). Maintain
upon opening the door.
the specified relative humidity by any convenient and suitable
5.2.1.2 For water storage tanks, position the reference
manner (Note 4).
temperaturemeasuringdeviceinareadablepositioninwateras
near as practical to the temperature recorder probe. Without
NOTE 3—Well insulated walls will substantially help maintain neces-
removing the reference temperature measuring device from the
sary conditions.
NOTE 4—A fog spray found suitable for this purpose is shown in Fig.
water, record the temperature readings of both the temperature
1.
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: C511 − 19 C511 − 21
Standard Specification for
Mixing Rooms, Moist Cabinets, Moist Rooms, and Water
Storage Tanks Used in the Testing of Hydraulic Cements
and Concretes
This standard is issued under the fixed designation C511; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope*
1.1 This specification includes requirements for mixing rooms where paste and mortar specimens are prepared; and for moist
cabinets, moist rooms, and water storage tanks where paste, mortar, and concrete specimens are stored.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. Values
in SI units shall be obtained by measurement in SI units or by appropriate conversion, using the Rules for Conversion and rounding
given in Standard IEEE/ASTM SI 10, of measurements made in other units.
1.3 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes
(excluding those in tables and figures) shall not be considered as requirements of this standard.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
C51 Terminology Relating to Lime and Limestone (as Used by the Industry)
E77 Test Method for Inspection and Verification of Thermometers
C125 Terminology Relating to Concrete and Concrete Aggregates
C219 Terminology Relating to Hydraulic and Other Inorganic Cements
IEEE/ASTM SI 10 Standard for Use of the International System of Units (SI): The Modern Metric System
3. Terminology
3.1 Definitions:
3.1.1 Refer to Terminology C125 and Terminology C219 for definitions of terms used in this test method.
This specification is under the jurisdiction of ASTM Committee C01 on Cement and is the direct responsibility of Subcommittee C01.95 on Coordination of Standards.
Current edition approved June 15, 2019Dec. 1, 2021. Published June 2019December 2021. Originally approved in 1968. Last previous edition approved in 20132019 as
C511 – 13.C511 – 19. DOI: 10.1520/C0511-19.10.1520/C0511-21.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C511 − 21
3.2 Definitions of Terms Specific to This Standard:
3.2.1 mixing room, n—a room with controlled temperature and relative humidity where cement paste and mortar specimens are
prepared.
3.2.2 moist cabinet, n—a compartmented storage facility of moderate dimensions with controlled temperature and relative
humidity.
3.2.3 moist room, n—a “walk-in” storage facility with controlled temperature and relative humidity, commonly called a fog room
when the prescribed relative humidity is achieved by the atomization of water.
4. Requirements for Cement Mixing Rooms
4.1 The temperature of the air in the vicinity of the mixing slab, molds, and base plates shall be maintained at 23.0 6 4.0 °C and
at a relative humidity of not less than 50 %.
4.2 The temperature of the mixing water used to prepare cement paste and mortar specimens shall be 23.0 6 2.0 °C.
5. Temperature Measuring Devices
5.1 Reference Temperature Measuring Device—used to verify the temperature recorder, must be accurate and readable to 0.5 ºC.
A copy of the certificate or report which verifies the accuracy shall be available in the laboratory.
NOTE 1—The ice-point method described in Test Method E77 may be used to ensure that no damage to the reference thermometer has occurred during
shipping.
5.2 Temperature Recorder—shall record temperatures every 15 min or less and shall be accurate and readable to 1 ºC. The data
from the recorder shall be evaluated at a minimum of once each week. A record of this evaluation documenting the date checked,
a confirmation that the data is within the required temperature range, and the name of the individual performing this evaluation
shall be maintained in the laboratory. (Note 2)
NOTE 2—This requirement may be satisfied by an initialed and dated temperature recorder chart. Brief changes in the temperature due to door openings
should be ignored.
5.2.1 The temperature recorder shall be verified at least every six months or whenever there is a question of accuracy.
5.2.1.1 For moist cabinets and rooms, position the reference temperature measuring device in a readable position in air as near
as practical to the temperature recorder probe. Keep the door closed for at least 5 min prior to taking readings. Record the
temperature readings of both the temperature recorder and the reference temperature measuring device. When taking these
readings, the reference temperature measuring device shall remain in the moist cabinet or room and read immediately upon opening
the door.
5.2.1.2 For water storage tanks, position the reference temperature measuring device in a readable position in water as near as
practical to the temperature recorder probe. Without removing the reference temperature measuring device from the water, record
the temperature readings of both the temperature recorder and the reference temperature measuring device after the temperatures
have stabilized.
5.2.1.3 Verify the accuracy of the temperature recorder by comparing the reading of the temperature recorder with that of the
reference temperature measuring device during the normal operation of the moist cabinet, moist room or water storage tanks. If
the difference between the temperature readings is greater than 1 ºC, the temperature recorder shall be adjusted to within 0.5 ºC
of the reference temperature measuring device.
6. Requirements for Moist Cabinets and Moist Rooms
6.1 General—Except during those times when specimens are being placed into or removed from storage, maintain the atmosphere
in a moist cabinet or moist room at a temperature of 23.0 6 2.0 °C and a relative humidity of not less than 95 %. Maintain
atmospheric conditions within a moist cabinet or moist room such that test specimens in storage are saturated with moisture to the
C511 − 21
degree needed to ensure that the exposed surfaces of all specimens in storage both look moist and feel moist (see Note 5). Equip
all moist cabinets and moist rooms with a temperature recorder. The use of humidity recording devices is optional. Keep shelves
on which fresh specimens are placed level.
6.1.1 The air temperature inside the moist cabinet or moist room shall be controlled with provisions made
...