Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
CSA B354.5-07 (R2016) — Design Calculations and Stability Criteria for Mobile Elevating Work Platforms
A technical overview of structural design standards for MEWP certification in Canada, including Category B requirements
Scope and Application
CSA B354.5-07 (R2016) — Mobile elevating work platforms — Design calculations and stability criteria — Symbols and specifications — defines the engineering methodology for calculating the structural strength, stability, and design loads applicable to mobile elevating work platforms (MEWPs). The standard applies to all MEWP types included in the broader B354 family, such as vertical-lift platforms (Group A) and boom-type or telescopic platforms (Group B). The document was reaffirmed in 2016 without substantive technical changes, confirming its ongoing relevance to Canadian manufacturers, certifiers, and regulatory authorities.
Tip: CSA B354.5-07 (R2016) is harmonized with ISO 16368:2010, facilitating cross-border acceptance of design calculations and stability test results for MEWPs operating in both Canadian and international markets.
The standard is primarily intended for design engineers, testing laboratories, and certification bodies. It sets out the calculation methods for determining loads (dead, live, wind, dynamic, and special loads) and verifying that the MEWP meets minimum stability limits under all specified operating conditions. The document also provides a comprehensive set of symbols and units to ensure consistent communication among stakeholders.
Classification of MEWPs
CSA B354.5-07 adopts a classification system that groups MEWPs by their movement capabilities and intended use:
- Group A: MEWPs for which the platform does not extend horizontally beyond the chassis footprint during normal operation (e.g., vertical scissor lifts and vertical mast lifts).
- Group B: MEWPs for which the platform is capable of extending horizontally beyond the chassis footprint (e.g., boom lifts, articulating lifts). This is the category referenced by the user as Category B (often referred to as Type B or Group B).
Within each group, the standard further distinguishes between wind conditions (normal and severe) and operational modes (transport, stationary, traveling with platform elevated). These classifications directly influence the stability factor requirements and the magnitude of design loads.
Technical Requirements for Design Calculations and Stability
CSA B354.5-07 mandates a rigorous engineering analysis that covers static and dynamic load scenarios. The design must demonstrate that the MEWP will not overturn under any foreseeable combination of loading, including platform overload, wind gust, and operational dynamic effects.
Stability Factor Requirements
The stability factor is defined as the ratio of the restoring moment about the tipping axis to the overturning moment produced by operating loads plus wind. The basic stability factors (without wind) are presented in the table below. For configurations that result in reduced stability margins (e.g., boom at maximum reach with elevated platform), higher minimum factors may be required.
| MEWP Group | Stability Condition | Minimum Stability Factor | Test Load Application |
|---|---|---|---|
| Group A (vertical lift) | Without wind, platform loaded to rated capacity | 1.5 | Load at platform center; then offset by 10% of platform width |
| Group B (horizontal reach) | Without wind, platform loaded to rated capacity | 1.5 | Load at platform center; offset 10% lateral and 30% longitudinal |
| All groups | With rated wind (normal operating wind) | 1.1 | Wind pressure per design category (e.g., 0.4 kN/m² at 10 m) |
| All groups | Dynamic effects (braking, starting, swing) | 1.0 (no tip allowed) | Vertical and horizontal dynamic factors (0.1 g to 0.5 g) |
Important: The stability factors above represent minimum values. Many certification bodies require a safety margin greater than 1.5 for Group B machines due to the higher risk associated with horizontal platform extension and operator movement.
Structural Design and Load Combinations
The standard specifies limit state design (LSD) or allowable stress design (ASD) methods. The following load combinations must be considered:
- Case 1: Self-weight + rated load + dynamic effects (vertical and horizontal).
- Case 2: Self-weight + rated load + prescribed wind (normal or severe).
- Case 3: Self-weight + test load (1.25 to 1.33 times rated capacity) for proof testing.
- Case 4: Self-weight + rated load + out-of-level (up to 5° side slope).
For Category B (Group B) MEWPs, the standard places special emphasis on the effects of platform swing, boom deflection, and ground conditions. The design must account for the additional overturning moment generated when the platform is rotated while carrying a rated load at maximum horizontal reach.
Implementation and Certification Highlights
Manufacturers seeking compliance with CSA B354.5-07 must produce a design calculation dossier that includes:
- Detailed structural model (FEA or analytical) of the chassis, mast/boom, platform, and outriggers.
- Stability calculations for every possible configuration (platform angle, boom extension, outrigger deployment).
- Load charts and capacity curves that define safe envelope limits.
- test procedures for verifying the stability factors physically (tilt table, load application).
Design tip: Integrate an electronic level sensor and load monitoring system that interlock when stability limits are approached. This can help exceed the minimum stability factor by 1.2 and reduce the need for manual calculations on every machine configuration during certification.
Testing and Verification
The standard requires both calculation and physical testing:
- Calculated verification: Demonstrate by analysis that each structural member and the complete MEWP meets the required stability factors and strength limits.
- Physical testing: Perform a stability test using the tilt-table method or by applying external loads to the platform until the machine reaches the theoretical overturning point. The measured moment must not be less than the calculated minimum stability factor.
For Category B machines, the standard requires additional dynamic tests simulating travel with platform elevated and swinging of the platform while loaded.
Compliance and Verification Notes
CSA B354.5-07 (R2016) is a reaffirmed standard, meaning that the 2007 edition was reviewed in 2016 and found to be technically current. No changes were made to the content. However, users must be aware that the standard may be referenced in other regulations (e.g., provincial occupational health and safety codes). Compliance with CSA B354.5-07 is typically a prerequisite for CSA B354.6 certification (MEWP safety requirements).
Critical: Failure to consider the combined effect of outrigger settlement, wind gust factor, and operator-induced dynamic loads has been a leading cause of MEWP tip-overs globally. CSA B354.5-07 requires that all three be factored into the stability analysis. Neglecting any one invalidates the certification.
Audit and Documentation
Certification bodies (e.g., CSA Group, TÜV, UL) will require:
- A design report summarizing all calculations and assumptions.
- Drawings showing load paths, welding symbols, and material specifications.
- Test reports with photographs, tilt-table data, and signed-off results.
- A declaration of conformity to CSA B354.5-07.
The standard also includes informative annexes that guide the user through stability calculations for non-standard configurations such as angled outriggers, monopole bases, and elevated platform travel. These annexes are recommended reading for design engineers new to the field.
Q: What does “Category B” mean in CSA B354.5-07?
A: “Category B” is another term for Group B MEWPs — machines whose platform can extend horizontally beyond the chassis footprint. These include boom lifts, articulating lifts, and telescopic handlers with platform. The standard imposes stricter stability requirements for Category B machines due to the higher tipping risk.
A: “Category B” is another term for Group B MEWPs — machines whose platform can extend horizontally beyond the chassis footprint. These include boom lifts, articulating lifts, and telescopic handlers with platform. The standard imposes stricter stability requirements for Category B machines due to the higher tipping risk.
Q: Is CSA B354.5-07 identical to ISO 16368?
A: Yes, CSA B354.5-07 is technically equivalent to ISO 16368:2010 (Mobile elevating work platforms — Design calculations — Safety requirements and test methods). The reaffirmation in 2016 confirmed this alignment, allowing manufacturers to use either standard for design compliance.
A: Yes, CSA B354.5-07 is technically equivalent to ISO 16368:2010 (Mobile elevating work platforms — Design calculations — Safety requirements and test methods). The reaffirmation in 2016 confirmed this alignment, allowing manufacturers to use either standard for design compliance.
Q: How often is the standard reviewed?
A: CSA standards are typically reviewed every five to ten years. The 2007 edition was reaffirmed in 2016; the next review is expected in the mid-2020s. Users should monitor the CSA website for updates regarding a potential revision.
A: CSA standards are typically reviewed every five to ten years. The 2007 edition was reaffirmed in 2016; the next review is expected in the mid-2020s. Users should monitor the CSA website for updates regarding a potential revision.
Q: Can I use CSA B354.5-07 for all types of work platforms, such as aerial work platforms?
A: The standard is specifically for mobile elevating work platforms. For other types (e.g., mast-climbing platforms, suspension scaffolds), refer to CSA B354.8 or CSA Z259 series. However, the calculation principles for stability can be adapted where applicable.
A: The standard is specifically for mobile elevating work platforms. For other types (e.g., mast-climbing platforms, suspension scaffolds), refer to CSA B354.8 or CSA Z259 series. However, the calculation principles for stability can be adapted where applicable.
© 2026 — This article is provided for general informational purposes. For authoritative guidance, consult the latest official CSA B354.5 document and a qualified professional engineer.