The National Ready Mixed Concrete Association
(NRMCA) administers a certification program for ready mixed concrete plants
and delivery vehicles which ensures that these facilities are in compliance
with industry standards and are capable of furnishing quality concrete. The
inspection is conducted by a licensed professional engineer, approved by
NRMCA, who goes through a thorough checklist during the inspection process.
Below are some important at-a-glance facts
about the program.
Administered since 1966, this
program verifies that the
production facility
complies with
the requirements of industry standards such as ASTM C94, AASHTO M157,
concrete plant manufacturers, and concrete truck mixer manufacturers.
Includes inspection
checklists for both the concrete production facility and the delivery
fleet.
The current version of the
inspection checklist is the 10th revision.
Ensures that the facility is
"physically capable of furnishing good-quality concrete.”
The NRMCA Technical Committee
constantly reviews specifications to ensure that the certification is in
compliance with updated standards.
A licensed professional
engineer inspects the concrete plant, and certification is valid for 2
years.
The delivery fleet is required
to be inspected and certified on an annual basis. Fleet inspection can
be conducted by the company, subject to audit by the inspecting
engineer.
The company official signs an
agreement to maintain the facility and accuracy of measuring devices in
compliance for the duration of the certification.
The certification of
production facilities is one part of a company’s quality system.
The program provides a means
for a ready mixed concrete company’s personnel to understand the basic
industry standards and requirements to produce ready mixed concrete.
It provides ready mixed
concrete companies a goal to ensure that production facilities are in
good operational order and to benchmark their quality goals.
The requirements to verify
accuracy of their batching systems ensures the production of uniform
concrete and serves to ensure that inventories of ingredients are
properly maintained with minimized waste.
Meets objective of multiple
AASHTO quality assurance and specification guides: QA-501 .03U for
pavements; QA-621 .03C for structures; 106.05 for plant inspections; and
Division II, Section 8.5 for manufacture of concrete.
More than 10 state highway
agencies, US Army Corps of Engineers, several commercial owners and
national design firms invoke the requirement for NRMCA certification of
production facilities in their project specifications.
The program is recognized in
ACI 301, Specification for Structural Concrete and the AIA MasterSpec.
NRMCA maintains a list of
about 300 approved inspectors or assistants.
Sections Addressed in the Checklist
Material
Storage and Handling, including cement, aggregates, water and admixtures.
Batching
Equipment including scales, weigh batchers, volumetric batching devices for
water, dispensers for liquid admixtures, accuracy of plant batching,
batching systems, and recorders.
Central
Mixer Ticketing System (which is required to qualify for Certification)
Delivery
Fleet, including truck mixers, agitators, non-agitating units and a summary
of fleet condition in which over 90% must be acceptable to qualify for
certification.
Requirements and
policy for the program are established by the NRMCA Research
Engineering and Standards (RES)
Committee. These are kept updated as standards and needs change. All
policies and revisions are approved by the NRMCA Board of Directors.
Plant Inspector's Guide
The Plant Inspector’s Guide instructs the inspector on the
intent of requirements of the certification program. It ensures that the
intent of each inspection item is clear to both the
inspector and to the producer owning the plant or delivery vehicle.
The guide is used as a basis to qualify and approve inspectors to conduct
plant inspections. The inspector can use an assistant under his/her charge
to conduct the physical inspection, followed by a review and attestation to
its accuracy. The inspecting engineer of record should be a licensed
professional engineer in the state where the plant is located.
Include this language in your specs
—
A sign of sound planning!
Suggested language for inclusion in Standards and
Specifications for Concrete Production
Facility Certification:
“The production facility
supplying hydraulic cement concrete shall have a
current Certification of Ready
Mixed Concrete Production
Facilities from the National Ready Mixed Concrete
Association, or equivalent.”
This program is flexible and
evolving.
Suggestions for improvement are
welcome.
