ASME PALD 10-1988 — Service Jacks

📐 ASME PALD 10-1988 is the volume of the Safety Standard for Portable Automotive Lifting Devices that covers service jacks. Developed by the ASME Committee on Portable Automotive Lifting Devices (PALD Committee) and approved as an American National Standard by ANSI on October 28, 1988, it sets the safety and performance requirements for portable lifting equipment used during automotive service, maintenance, and storage. The defining characteristic of a service jack is that it is used for lifting, but not sustaining, a partial vehicular load — so it must always be paired with vehicle support stands (covered by PALD-4) before anyone goes underneath a raised vehicle.

1. Scope and General Framework 📌

This volume applies to self-contained service jacks used for lifting, but not sustaining, a partial vehicular load during automotive service, maintenance, and storage. Its purposes are threefold: first, to guard against and mitigate injury to workers and otherwise protect life, limb, and property by prescribing safety requirements; second, to provide direction to purchasers, owners, employers, supervisors, and others responsible for its application; and third, to guide governments and other regulatory bodies in developing and enforcing appropriate safety directives.

The Standard does not apply to similar lifting devices designed and manufactured for other commercial or industrial use, such as those within the scope of ASME/ANSI B30.1, Jacks. Operation and maintenance instructions are intended for general applications; the equipment manufacturer or supplier should be consulted for specific operating and maintenance instructions.

2. Definitions and the Four Classifications 🔧

Service jacks are divided into four classifications based on power and force-transmission method — the foundation of the technical system:

• Hydraulic service jack: the lift arm is actuated by a mechanism using a relatively incompressible fluid, such as oil, as the force-transmitting medium.
• Pneumatic service jack: the lift arm is actuated by a mechanism using compressed air as the force-transmitting medium.
• Pneumatic/hydraulic service jack: compressed air drives a hydraulic pump, which then raises the load.
• Mechanical service jack: the lift arm is actuated by mechanical means such as levers, cables, gears, screws, ratchets and pawls, or other devices.

Key defined terms include lift arm (the main lifting member transferring force from the power unit to the saddle), saddle (the platform contacting the load), operating controls (the mechanisms manipulated in extending or retracting the jack), internal load limiting device (a device that limits lifting capacity), overload (a load exceeding rated capacity), and functional damage (any detrimental permanent deformation of the structure or saddle that causes loss of sealing, loss of load, or failure to meet design qualification limits).

3. Design Requirements and Key Technical Criteria 📏

Section 3 sets design requirements focused on structural strength, stability, and overload protection. The design must ensure the lift arm, saddle, and base suffer no functional damage at rated capacity and remain stable on a hard, level surface. For hydraulic and pneumatic/hydraulic units, additional provisions cover hydraulic sealing, filler plug placement, pressure relief, and internal load limiting.

4. Marking and Design Qualification Testing 🏷️

Section 4 requires clear, permanent marking of the manufacturer’s name or trademark, rated capacity, model, and accompanying safety warnings. Section 5, Design Qualification Testing, is the central safety gate: a manufacturing sample must pass a proof load test, typically at 1.5 times rated capacity, verifying no functional damage, sealing failure, or permanent deformation within the prescribed hold time.

5. Operation, Maintenance, and Inspection 🛠️

Section 7 governs operation, maintenance, and inspection. A service jack is used only to lift part of a vehicle and must never alone support the whole vehicle or allow a person underneath. The correct sequence: raise the vehicle locally with the service jack, place vehicle support stands (PALD-4) under frame or specified support points, lower the jack slowly to transfer the load onto the stands, and only then work beneath the vehicle.

• Pre-use check: confirm no leaks, no base cracks, intact saddle, free-moving controls.
• Placement: on hard level ground, saddle aligned to the specified lift point, load centered.
• Prohibitions: no overload, no off-center load, no working underneath while lifted, no prolonged support by the jack.
• Maintenance: periodic hydraulic oil level check (filler plug), seals and moving parts; remove from service on functional damage.

6. Engineering Practice Essentials 🚧

• 🔍 Selection: match rated capacity with margin to vehicle curb weight and lift-point geometry; choose pneumatic/hydraulic or large hydraulic jacks for heavy vehicles.
• 🔧 Pair with support stands: the jack and vehicle support stands are a mandatory pair — any under-vehicle work requires the stand transfer first.
• 📊 Shop management: maintain a jack register and periodic inspection system; tag out expired or damaged units.
• 📋 Warnings & training: brief operators on the “lift, don’t support” principle and on tipping/slipping hazards.

7. Frequently Asked Questions ❓