ISO/IEC 17025 Accredited Proof Load Testing
Worker safety and equipment reliability depend on lifting systems performing as designed. Our national network of local brands delivers precise proof load testing so you can verify equipment performance, protect personnel, and reduce costly risks.
Our Proof Load Testing Services
Hoists, cranes, and lifting equipment must reliably handle their rated loads to prevent accidents and equipment failures.
When lifting systems fail, the consequences can be severe—serious injuries, fatalities, property damage, and liability exposure. The Accredited Labs network provides comprehensive proof load testing to confirm that lifting equipment performs safely and meets manufacturer specifications and regulatory safety requirements.
Our Process
Proof load testing involves applying controlled test loads to lifting equipment to verify structural integrity, load-bearing capacity, and safe operation at or above rated working loads. Each piece of equipment is evaluated against manufacturer specifications and regulatory safety standards.
Certified technicians apply predetermined test loads using calibrated weights or hydraulic testing systems while monitoring structural response, mechanical function, and safety components. The testing confirms that all load-bearing elements, safety devices, and control systems operate correctly under maximum and specified overload conditions.
All proof load testing follows OSHA regulations, ANSI standards, and industry safety protocols to deliver consistent, reliable verification. Each tested item receives comprehensive documentation certifying load capacity and safety compliance—supporting regulatory requirements, insurance documentation, and workplace safety programs.
Types of Lifting Equipment We Test
Our comprehensive proof load testing services cover the complete spectrum of lifting and material handling equipment used across industries:
- Overhead Bridge Cranes: Industrial bridge cranes, gantry cranes, and jib cranes used in manufacturing, warehousing, and construction applications. Testing verifies structural integrity of bridges, runways, hoists, and all load-bearing components under maximum rated loads.
- Mobile and Tower Cranes: Construction cranes, truck-mounted cranes, and tower cranes require proof testing to verify their load capacity and stability under various boom positions and load configurations. Testing ensures safe operation across the crane's working envelope.
- Chain Hoists and Electric Hoists: Suspended hoisting equipment including chain hoists, wire rope hoists, and electric hoists require testing to verify load chain integrity, motor capacity, and brake system performance under rated loads and overload conditions.
- Material Lifts and Personnel Platforms: Equipment designed to lift materials or personnel must undergo proof testing to ensure platform integrity, lifting mechanism capacity, and safety system functionality. This includes construction hoists, personnel lifts, and material handling platforms.
- Winches and Pulling Equipment: Industrial winches, come-alongs, and pulling devices require testing to verify their rated capacities and ensure safe operation under maximum load conditions. Testing verifies cable integrity, drum capacity, and braking system performance.
- Rigging Hardware and Lifting Accessories: Slings, shackles, hooks, spreader beams, and other rigging hardware require proof testing to verify their load ratings and ensure safe use in lifting operations. Testing verifies that accessories can handle their rated working loads with appropriate safety factors.
- Scaffolding and Temporary Structures: Temporary lifting structures, scaffolding systems with integrated hoists, and specialized lifting fixtures require proof testing to verify their structural integrity and load-bearing capacity under design loads.
- Specialized Lifting Equipment: Custom lifting devices, material handling equipment, and application-specific lifting systems require customized proof testing procedures based on their design, intended use, and safety requirements.
- Lifting Magnets and Vacuum Systems: Electromagnetic and vacuum lifting systems require specialized testing to verify their holding capacity and safety release systems under rated load conditions and power failure scenarios.
Find Proof Load Testing Services
-
Accutek Lab
Accutek Lab has been providing reliable and cost-effective pipette calibration services across the United States since 1996.
Calibration ServicesPipette Calibration -
Aldinger
Since 1972, Aldinger has been providing top-quality calibration services for test and measurement equipment in Texas and beyond.
Calibration ServicesDimensional Calibration Electrical Calibration Flow Calibration Force Calibration Mass Calibration +7 more -
Cal-Cert
Cal-Cert is committed to providing the highest level of calibrations and certification service to our customers.
Calibration ServicesForce Calibration Torque Calibration Mass Calibration Pressure Calibration Temperature Calibration +3 more -
Cal-Labs
Cal-Labs has provided quality calibration in Southern California since 1977. We are A2LA accredited to ISO 17025.
Calibration ServicesDimensional Calibration -
Calibration Services Inc.
Calibration Services, Inc. (CSI) is an on-site and in-house calibration firm specializing in calibration and service of mechanical testing devices.
Calibration ServicesForce Calibration Torque Calibration Mass Calibration Dimensional Calibration Pressure Calibration +3 more -
Cal Tec Process Management
The calibration specialists at CTPM have been providing precision calibration and quality assurance since 1987.
Calibration ServicesForce Calibration Torque Calibration Mass Calibration Dimensional Calibration Pressure Calibration +2 more -
Calser Calibrations
Since 1979, Calser Calibrations has delivered trusted, precision calibration services backed by a commitment to quality and reliability.
Calibration ServicesConstruction Materials Testing Equipment Calibration Dimensional Calibration Force Calibration Mass Calibration Pressure Calibration +3 more -
CMG Sales, Inc.
CMG Sales, Inc. is a leading manufacturer sales representative and ISO 17025 accredited calibration laboratory providing services to manufacturers nationwide.
Calibration ServicesCoating Thickness Calibration Color Calibration -
Color Calibration Group
Color Calibration Group has been providing professional calibration services for all your color, light, and viscosity calibration needs for over 25 years.
Calibration ServicesCoating Thickness Calibration Color Calibration -
ETI Precision
ETI has been a leader in the calibration, repair, and sale of test and measurement equipment since 1994, and covers all 50 states.
Calibration ServicesElectrical Calibration Force Calibration Torque Calibration Dimensional Calibration Pressure Calibration +2 more -
Holts Precision, Inc.
For over 60 years Holts Precision, Inc. has performed calibrations & repairs on all major brands of gaging equipment.
Calibration ServicesDimensional Calibration Electrical Calibration Force Calibration Mass Calibration Pressure Calibration +2 more -
Huston-DePue
Established in 1960, HDCL is staffed by experienced professionals who understand the critical role accurate measurement plays in quality control and regulatory compliance.
Calibration ServicesFlow Calibration Force Calibration Torque Calibration Mass Calibration Dimensional Calibration +3 more -
Instrument Technologies, Inc.
For over three decades, Instrument Technologies, Inc. (ITI) has been a trusted partner for regulated industries seeking precision, compliance, and operational reliability.
Calibration ServicesFlow Calibration Mass Calibration Dimensional Calibration Pressure Calibration Time Calibration +1 more -
IPM, Inc.
Industrial Process Measurement, Inc. has been in the instrument supply, service and calibration business for over 30 years.
Calibration ServicesDimensional Calibration Electrical Calibration Flow Calibration Force Calibration Humidity Calibration +6 more -
J & J Calibration Service
J&J Calibration Service, an ISO-17025 accredited company, offers unmatched mobile calibration capabilities and laboratory calibration services.
Calibration ServicesDimensional Calibration Electrical Calibration Force Calibration Pressure Calibration Temperature Calibration +1 more -
OCS Technologies
Founded in 1930, OCS Technologies is a trusted multi-discipline calibration service provider as well as leading product distributor.
Calibration ServicesForce Calibration Torque Calibration Mass Calibration Dimensional Calibration Pressure Calibration +3 more -
OnCal
With over 23 years of experience in pipette calibration in the Pacific Northwest, the OnCal Corporation guarantees seamless and dependable metrology services.
Calibration ServicesPipette Calibration -
Polymer Testing Instruments
Since 1996 Polymer Testing Instruments Inc. has provided high quality service and calibration of equipment for the rubber, plastics, and energy industries.
Calibration ServicesForce Calibration Torque Calibration Dimensional Calibration Pressure Calibration Temperature Calibration +1 more -
Precision Calibration Systems
PCS is a full-service ISO 17025 Accredited calibration laboratory, founded with the goal of providing reliable and accurate instrument calibration service.
Calibration ServicesFlow Calibration Force Calibration Torque Calibration Mass Calibration Dimensional Calibration +4 more -
Quality Control Services
Quality Control Services is an established, accredited calibration services and laboratory equipment company with over 40 years of experience.
Calibration ServicesForce Calibration Mass Calibration Pipette Calibration Temperature Calibration -
Quality Surveillance, Inc.
QSI has been providing Los Angeles, Ventura, Santa Barbara and Santa Clarita Counties with reliable and cost effective metrology services since 1992.
Calibration ServicesDimensional Calibration Force Calibration Mass Calibration Pressure Calibration Temperature Calibration +3 more -
Scale Service & Supply
From laboratory balances to truck scales, Scale Service & Supply has been providing precision calibration for weighing systems since 1987.
Calibration ServicesScale Calibration Mass Calibration -
Servo Innovations
Servo Innovations, founded in 2005, has earned industry-wide trust for its accredited calibration, repair, and technical services.
Calibration ServicesFlow Calibration Force Calibration Torque Calibration Dimensional Calibration Pressure Calibration +1 more -
Tescom Calibration Services
Tescom Calibration Services has provided sales, repair, and calibration of telecom test equipment since 1982.
Calibration ServicesFlow Calibration Force Calibration Torque Calibration Mass Calibration Dimensional Calibration +4 more -
Trident Calibration Labs
Serving the greater Phoenix area, Trident Calibration Labs has more than 100 years of combined calibration experience.
Calibration ServicesElectrical Calibration RF & Microwave Calibration Dimensional Calibration Force Calibration Mass Calibration +6 more -
Tru Cal International
Serving as an asset to countless businesses in a variety of industries, Tru Cal International has specialized in test equipment calibration since 1992.
Calibration ServicesElectrical Calibration Dimensional Calibration Force Calibration Pressure Calibration RF & Microwave Calibration +3 more -
Utah Scale Center
Utah Scale Center offers servicing and calibrating of industrial scales across the Rocky Mountain Region, with 70+ years of experience.
Calibration ServicesScale Calibration -
Washington Calibration
Washington Calibration has been providing customers with quality gage repair services for all their inspection measuring instruments for more than 34 years.
Calibration ServicesDimensional Calibration Force Calibration Mass Calibration Pressure Calibration Temperature Calibration +1 more
No companies found
Try adjusting your filters to see more results.
Request a Calibration Service from the Accredited Labs Network
Audit-Ready Calibration in 3 Simple Steps
Submit Your Equipment List
Send us a list of the equipment you need calibrated, and we’ll provide a tailored quote with clear pricing—no hidden fees.
Schedule Your Calibration
Choose a convenient time for a mobile or on-site equipment calibration. Our certified technicians ensure precision and compliance with ISO/IEC 17025 standards.
Stay Compliant & Audit-Ready
Receive detailed calibration reports and certification, giving you peace of mind for audits and operational excellence.
Frequently Asked Questions
-
What is the difference between proof load testing and a standard load rating for lifting equipment?
A load rating is a specification indicating the maximum safe working load for a piece of lifting equipment under defined conditions. Proof load testing is a physical test in which the equipment is subjected to a load exceeding its rated capacity — typically by a defined percentage — to verify that it can safely handle its rated load without permanent deformation or failure. Proof testing provides physical evidence of structural integrity that a rating specification alone cannot provide.
-
What types of equipment typically require proof load testing?
Proof load testing is commonly required for overhead lifting equipment including hoists, cranes, rigging hardware, slings, shackles, eyebolts, lifting beams, and custom below-the-hook lifting devices. It may also be required for fall arrest anchors, structural tie-down points, and other safety-critical load-bearing components. Requirements vary by industry, jurisdiction, and applicable standards.
-
How often is proof load testing required, and what triggers retesting?
Proof load testing requirements vary depending on applicable regulations, industry standards, and equipment manufacturer recommendations. Retesting is typically triggered by events such as repair or modification of the equipment, a suspected overload or shock load event, a change in intended use or load rating, or a defined time interval as required by the governing standard or a facility inspection program.
-
What documentation is produced after proof load testing, and why is it important?
After proof load testing, a formal test report is issued documenting the equipment tested, the test load applied, the method and reference standard used, and the results of the test. This documentation is essential for demonstrating compliance with regulatory requirements, supporting equipment certification, satisfying insurance or customer requirements, and providing a traceable record for future inspections or audits.
