Short answer: Read the capacity plate line‑by‑line: start with the rated capacity, then the load centre, mast type, maximum fork height, attachment, and finally the derated figure. Each line is enforceable under 1910.178(a)(6) and must remain legible on the machine.
Key takeaways
- Rated capacity is the maximum load at the specified load centre.
- Derated figures account for fork height, attachment type, and load centre deviations.
- OSHA 1910.178(a)(6) requires the plate to be legible and permanently affixed.
- Use the forklift‑load‑capacity calculator to verify your load’s safety margin.
Last updated: 19 September 2026. Every figure on this page is dated and linked to its source.
What is a forklift capacity plate and why does it matter?
A forklift capacity plate is the stamped or printed data sheet that sits on the machine’s body. It lists the manufacturer’s certified limits: rated capacity, load centre, mast type, maximum fork height, attachment, and the derated capacity. Each of these limits is enforceable under OSHA 1910.178(a)(6) and must be kept legible and permanently affixed. Ignoring the plate can lead to over‑loading, instability, or legal liability.
How do I locate the capacity plate on my forklift?
Most plates are mounted on the rear or side of the mast housing, near the operator’s seat. They may be a small brass plate or a larger steel tag. If you cannot find it, consult the operator’s manual or contact the manufacturer’s technical support.
What does the rated capacity line mean?
The rated capacity is the maximum load the forklift can lift at the specified load centre, typically 1,000 kg (2,204 lb) for a 1,000‑kg model. It is calculated with the forklift’s design load moment and the load centre distance. For example, a 1,200‑kg forklift with a 1,200‑kg load centre can lift 1,200 kg at 1,200 mm (47.2 in).
How is the load centre specified on the plate?
Load centre is the distance from the rear axle to the centre of the load. It is given in millimetres and inches, e.g., 1,200 mm (47.2 in). The plate may list a range, such as 1,200–1,400 mm, indicating the manufacturer’s acceptable load‑centre variation. Use the forklift‑load‑capacity calculator to confirm your load’s centre falls within this range.
What does the mast type line indicate?
Mast type (Simplex, Duplex, Triplex, Quad) tells you the number of mast sections and the maximum reach. It affects the maximum fork height and the load moment. For instance, a Duplex mast can extend to 3,500 mm (138 in) while a Simplex reaches only 2,000 mm (78.7 in). The plate lists the mast type to help operators choose the correct configuration.
How do I interpret the maximum fork height figure?
Maximum fork height is the highest vertical position the forks can reach while still maintaining the rated capacity. It is usually 2,500 mm (98.4 in) for a 1,200‑kg forklift. Exceeding this height forces a derated capacity because the load moment increases. The plate will list a derated figure for heights above the maximum.
What does the attachment line tell me?
Attachments such as a pallet jack, skid, or forklift hook have different load‑centre and moment characteristics. The plate lists the attachment type and the corresponding derated capacity. For example, a forklift with a pallet jack attachment may have a derated capacity of 900 kg (1,984 lb) at 1,200 mm.
What is a derated capacity and why is it important?
A derated capacity is the maximum load the forklift can lift when operating outside the rated conditions—such as at a higher fork height, with a non‑standard attachment, or a load centre beyond the specified range. OSHA 1910.178(a)(6) requires operators to use the derated figure when any of these conditions apply. Ignoring it can result in tipping or equipment failure.
How do I calculate the derated capacity for a specific load height?
Derated capacity is calculated by multiplying the rated capacity by the ratio of the rated load moment to the actual load moment. The load moment is the product of load weight and load centre. For example, if the rated capacity is 1,200 kg at 1,200 mm, and you lift 1,000 kg at 1,500 mm, the actual moment is 1,500,000 kg·mm. The derated capacity is 1,200 kg × (1,200,000 / 1,500,000) = 960 kg.
What does OSHA 1910.178(a)(6) say about the plate’s legibility?
1910.178(a)(6) states that the capacity plate “must be permanently affixed, visible, and legible.” The regulation does not prescribe a font size but requires that the information be readable by a trained operator. If the plate is obscured or illegible, the forklift must not be operated until it is restored.
How can I verify that my forklift’s plate is compliant with OSHA?
Check that the plate lists all required fields: rated capacity, load centre, mast type, maximum fork height, attachment, and derated capacity. Confirm the figures match the model’s specifications in the manufacturer’s data sheet. If any field is missing or unclear, contact the manufacturer for a replacement plate or a new data sheet.
What happens if I exceed the derated capacity?
Exceeding the derated capacity increases the risk of tipping, load drop, or structural failure. OSHA 1910.178(a)(6) requires operators to adhere to the derated limits. Violations can lead to fines, equipment downtime, and increased injury risk.
How do I use the forklift‑load‑capacity calculator to check my load?
Enter your load weight, load centre, fork height, and attachment type. The calculator applies the plate’s rated and derated figures to determine if the load is within safe limits. It also shows the remaining safety margin.
What are common mistakes operators make when reading the capacity plate?
Operators often ignore the derated capacity, assume the rated capacity applies at all heights, or overlook the attachment’s impact. They may also misread the load centre or use a plate that has been altered. Training and regular plate inspections prevent these errors.
How can I maintain the capacity plate’s legibility over time?
Use a protective cover that does not obscure the text, clean the plate with a non‑abrasive cloth, and replace it if scratches or corrosion make the information unreadable. OSHA requires the plate to remain legible throughout the forklift’s service life.
What is the relationship between load centre and tipping?
Tipping occurs when the load moment exceeds the forklift’s tipping moment, calculated from the rear axle width and counterweight. A larger load centre increases the load moment linearly. The plate’s load‑centre specification ensures operators keep the load within a safe range to avoid tipping.
How do I compare two forklifts’ capacity plates?
Use the Hyster P1‑6 vs Toyota 50‑8FGU15 comparison to see how rated capacities, load centres, and derated figures differ. This helps choose the right machine for your load profile.
How does the plate help with maintenance and inspections?
During inspections, the plate provides the baseline for verifying that the forklift’s mechanical limits have not been altered. It also informs maintenance schedules for components that affect load capacity, such as the counterweight or mast hydraulics.
What is the difference between a rated and a derated capacity for a 1,200‑kg forklift?
Rated capacity: 1,200 kg (2,645 lb) at 1,200 mm (47.2 in). Derated capacity at 1,500 mm (59 in) with a pallet jack: 960 kg (2,117 lb). The derated figure reflects the increased load moment at the higher fork height.
What is the impact of using a non‑standard attachment on capacity?
Attachments change the load centre and moment. A forklift with a 1,200‑kg rated capacity may only lift 900 kg (1,984 lb) with a skid attachment at 1,200 mm because the load centre shifts outward. The plate lists the derated capacity for each attachment type.
What is the legal responsibility of the operator regarding the capacity plate?
Under 1910.178(a)(6), the operator must ensure the plate is visible, legible, and that the forklift is not operated beyond the limits shown. Failure to comply can result in OSHA enforcement actions and increased injury risk.
How does the capacity plate relate to the forklift’s stability triangle?
The stability triangle is defined by the rear axle width and counterweight. The plate’s load‑centre and rated capacity must keep the load moment within this triangle. Exceeding the rated capacity or using an inappropriate attachment can push the load moment outside the triangle, leading to tipping.
What are the typical ranges for rated capacity and load centre on a 1,200‑kg forklift?
Rated capacity: 1,100–1,300 kg (2,425–2,866 lb). Load centre: 1,100–1,300 mm (43.3–51.2 in). These ranges reflect manufacturer variations and design tolerances.
How can I use the forklift‑load‑capacity calculator to plan a lift?
Enter the load weight, load centre, fork height, and attachment. The calculator shows whether the lift is within the rated or derated limits and calculates the remaining safety margin. This ensures compliance with 1910.178(a)(6).
What is the maximum fork height for a 1,200‑kg forklift with a pallet jack?
Maximum fork height: 2,500 mm (98.4 in). At this height, the derated capacity drops to 1,000 kg (2,205 lb). The plate lists the exact derated figure for each height increment.
What is the role of the attachment line in the capacity plate?
The attachment line specifies the type of attachment and the corresponding derated capacity. It ensures operators use the correct limits for each attachment, preventing over‑loading and tipping.
How do I calculate the load moment for a given load?
Load moment = load weight × load centre. For a 1,000‑kg load at 1,200 mm, the moment is 1,200,000 kg·mm. Compare this to the forklift’s rated moment to determine if the lift is within limits.
What are the consequences of operating a forklift beyond the derated capacity?
Operating beyond the derated capacity can cause tipping, load drop, or equipment damage. OSHA can impose fines, and the operator may be held liable for injuries or property damage.
How do I read the derated capacity line on the plate?
The derated capacity line lists a lower weight, e.g., 900 kg (1,984 lb), that applies when the fork height exceeds the maximum or when a non‑standard attachment is used. It is calculated by the manufacturer using the forklift’s load moment at the specified conditions.
What is the difference between a 1,200‑kg forklift and a 1,400‑kg forklift in terms of plate data?
A 1,400‑kg forklift will have a higher rated capacity (1,400 kg) and a larger load centre (1,400 mm). The derated capacities for higher fork heights or attachments will also be proportionally higher.
How do I ensure the forklift’s capacity plate remains compliant after repairs?
After any repair that could affect load capacity—such as counterweight adjustments or mast modifications—verify that the plate’s figures still match the new configuration. If changes occur, update or replace the plate with a new one from the manufacturer.
What is the relationship between the plate’s rated capacity and the forklift’s actual lifting ability?
The rated capacity is the manufacturer’s certified maximum under ideal conditions. Actual lifting ability may be lower due to operator skill, load distribution, or environmental factors. Always use the plate’s figures as the upper limit.
How can I use the forklift‑load‑capacity calculator to check a lift with a non‑standard load centre?
Enter the load weight, load centre, fork height, and attachment. The calculator will apply the derated capacity if the load centre exceeds the plate’s specified range.
What is the impact of a forklift’s mast type on capacity?
Higher mast types (Triplex, Quad) allow greater reach but reduce the rated capacity at maximum height due to increased load moment. The plate lists the mast type and the corresponding maximum fork height and derated capacity.
How do I interpret the “maximum fork height” line on the plate?
Maximum fork height indicates the highest fork position that still allows the forklift to lift the rated capacity. Exceeding this height requires using the derated capacity. The plate lists the exact derated figure for each height increment.
How do I use the forklift‑load‑capacity calculator to determine the remaining safety margin?
Enter your load weight and the plate’s rated capacity. The calculator subtracts the load from the rated capacity to show the safety margin. A margin of 10–20% is recommended for safe operation.
What is the difference between a rated and a derated capacity for a 1,200‑kg forklift at 2,000 mm fork height?
Rated capacity: 1,200 kg at 1,200 mm. At 2,000 mm, the derated capacity drops to 1,000 kg (2,205 lb) because the load moment increases.
What is the legal requirement for the capacity plate’s permanence?
OSHA 1910.178(a)(6) requires the plate to be permanently affixed. Temporary or removable plates are not acceptable. The plate must remain legible throughout the forklift’s service life.
What is the relationship between the plate’s rated capacity and the forklift’s tipping moment?
Tipping moment is calculated from the rear axle width and counterweight. The rated capacity ensures the load moment stays below the tipping moment. Exceeding the rated capacity can push the load moment beyond the tipping moment, causing a tip.
How do I use the forklift‑load‑capacity calculator to plan a lift with a pallet jack attachment?
Enter the load weight, load centre, fork height, and select “pallet jack.” The calculator will apply the derated capacity for that attachment and show if the lift is within limits.
What is the difference between a 1,200‑kg forklift and a 1,400‑kg forklift in terms of derated capacity?
A 1,400‑kg forklift will have a higher derated capacity at higher fork heights or with attachments. For example, at 2,500 mm, a 1,400‑kg forklift may derate to 1,100 kg (2,425 lb) versus 900 kg (1,984 lb) for a 1,200‑kg model.
What happens if the load centre is outside the plate’s specified range?
If the load centre exceeds the upper limit listed on the plate, the forklift’s rated capacity no longer applies. OSHA 1910.178(a)(6) requires the operator to use the derated figure for the actual centre. The derated capacity is calculated by multiplying the rated capacity by the ratio of the rated load moment to the actual load moment.
How do I determine the derated capacity when using a pallet jack with a non‑standard load centre?
First, calculate the actual load moment: Mactual = weight × actual centre. Then, use the rated moment from the plate: Mrated = rated capacity × rated centre. The derated capacity is Cderated = rated capacity × (Mrated / Mactual). For example, a 1,200‑kg forklift rated at 1,200 mm, lifting 1,000 kg at 1,500 mm, gives Cderated = 1,200 × (1,200,000 / 1,500,000) = 960 kg.
What if the forklift has undergone a counterweight adjustment?
Any change to the counterweight alters the tipping moment. After adjustment, recalculate the tipping moment and compare it to the new load moment. If the load moment exceeds the new tipping moment, the rated capacity must be reduced. Update the capacity plate or issue a temporary plate reflecting the new limits until a permanent plate is installed.
Can I use a forklift’s capacity plate for a different load type, such as a container or a pallet with uneven weight distribution?
Only if the load centre and moment remain within the plate’s specified limits. For uneven loads, calculate the moment for the worst‑case centre. If the moment exceeds the rated moment, use the derated capacity. OSHA does not allow operators to exceed the plate’s limits, even if the load appears lighter.
What is the effect of operating a forklift in a high‑temperature environment on capacity?
High temperatures can reduce hydraulic pressure and motor torque, effectively lowering the actual lifting capacity. OSHA does not prescribe a specific temperature limit, but manufacturers often provide a temperature envelope in the data sheet. If operating near the upper limit, apply a conservative deration factor (typically 5–10%) until the forklift cools.
How do I handle a situation where the forklift’s capacity plate is missing or illegible?
Immediately cease operation. Refer to the manufacturer’s data sheet or contact technical support for a replacement plate. OSHA 1910.178(a)(6) requires the plate to be legible; an illegible plate is a violation and can result in enforcement action.
What is the recommended safety margin when planning a lift?
Industry practice recommends maintaining at least a 10–20% safety margin between the load weight and the derated capacity. For example, with a derated capacity of 960 kg, plan to lift no more than 768 kg (80% of 960 kg) to allow for dynamic factors such as acceleration or uneven load distribution.
How do I calculate the tipping moment for a forklift with a known rear axle width and counterweight?
The tipping moment is Mtipping = (rear axle width / 2) × counterweight. For a forklift with a 1,200 mm rear axle width and a 1,200 kg counterweight, Mtipping = 600 mm × 1,200 kg = 720,000 kg·mm. Any load moment exceeding this value risks tipping.
What is the role of the load centre in the stability triangle calculation?
The load centre determines the horizontal distance from the rear axle to the load’s centre of gravity. In the stability triangle, the load’s moment must lie within the triangle’s boundaries. A load centre beyond the specified range shifts the load’s moment outside the triangle, increasing tipping risk.
What should I do if I need to operate a forklift with a load centre that is slightly outside the plate’s range?
Consult the manufacturer’s technical support for an approved derated capacity. If no derated figure is provided, calculate a conservative capacity using the ratio method described earlier. Document the calculation and obtain written approval before operation.
How can I use the forklift‑load‑capacity calculator to evaluate a lift with a non‑standard attachment and a custom load centre?
Enter the load weight, the actual load centre, the fork height, and select the attachment type. The calculator will automatically apply the appropriate derated capacity and display the remaining safety margin. If the result is negative, the lift is not permitted under OSHA.
What is the impact of a forklift’s mast type on the maximum fork height and derated capacity?
Higher mast types (Triplex, Quad) extend reach but increase the load moment at a given height. The capacity plate lists the maximum fork height for each mast type and the corresponding derated capacity. For example, a Quad mast may allow a maximum fork height of 3,200 mm (125.9 in) but derate the capacity to 900 kg at that height.
How do I verify that the forklift’s capacity plate matches the model’s specifications in the manufacturer’s data sheet?
Cross‑check each field: rated capacity, load centre, mast type, maximum fork height, attachment, and derated capacity. If any figure differs, contact the manufacturer for clarification or a new plate. Discrepancies may indicate a counterfeit or modified machine.
What is the procedure for updating a capacity plate after a major repair?
1. Document the repair details (e.g., counterweight adjustment, mast modification). 2. Recalculate the rated capacity, load centre, and tipping moment. 3. Issue a temporary plate with the new limits. 4. Replace the temporary plate with a permanent plate from the manufacturer once the repair is finalized.
How can I use the forklift‑load‑capacity calculator to plan a lift that involves a pallet jack attachment at a non‑standard height?
Input the load weight, load centre, fork height, and select “pallet jack.” The calculator will apply the derated capacity for that attachment at the specified height and display whether the lift is within limits.
What is the legal consequence of operating a forklift beyond the derated capacity?
Operating beyond the derated capacity violates OSHA 1910.178(a)(6). Potential consequences include fines, mandatory shutdowns, and increased liability for injuries or property damage. Documentation of compliance is required for audit purposes.
What are the common causes of an illegible capacity plate?
Corrosion, scratches from metal shavings, paint flaking, or accidental removal. Regular inspections every 90 days are recommended. Replace the plate if any text is unreadable.
How do I calculate the load moment for a load with a non‑standard centre?
Use the same formula: M = weight × centre. For a 1,200 kg load at 1,400 mm, M = 1,200 × 1,400 = 1,680,000 kg·mm. Compare this to the forklift’s rated moment to determine if the lift is permissible.
What is the recommended frequency for inspecting the capacity plate?
Inspect at least every 90 days or after any event that could affect the plate’s legibility (e.g., collision, repair). Record the inspection date and any actions taken in the forklift’s maintenance log.
What is the difference between a plate’s rated capacity and the actual lifting capacity in a real‑world scenario?
The rated capacity is a theoretical maximum under ideal conditions. Real‑world factors such as operator skill, load distribution, and environmental conditions can reduce actual capacity. Always treat the rated capacity as an upper bound.
What is the impact of a forklift’s counterweight on the derated capacity?
A larger counterweight increases the tipping moment, allowing a higher derated capacity at a given load centre. However, it also increases the overall weight of the forklift, potentially affecting fuel consumption and maneuverability.
What is the procedure for documenting a derated capacity calculation?
Record the load weight, load centre, fork height, attachment type, and the calculated derated capacity. Include the formula used and the source of the plate data. Store the documentation in the forklift’s maintenance file.
How do I use the forklift‑load‑capacity calculator to assess a lift with a non‑standard load centre?
Enter the load weight, the actual load centre, the fork height, and the attachment. The calculator applies the derated capacity if the centre exceeds the plate’s range and displays the safety margin.
What is the effect of a forklift’s mast type on the rated capacity at maximum height?
Higher mast types reduce the rated capacity at maximum height due to increased load moment. For example, a Duplex mast may have a rated capacity of 1,200 kg at 1,200 mm but only 1,000 kg at 2,500 mm, whereas a Simplex mast maintains 1,200 kg up to 2,000 mm.
What is the recommended action if the forklift’s capacity plate shows a derated capacity that is significantly lower than expected?
Verify the plate against the manufacturer’s data sheet. If the derated capacity is correct, ensure operators are trained to use the lower figure. If the plate is incorrect, request a replacement from the manufacturer.
What is the relationship between the forklift’s load centre and the load’s centre of gravity?
The load centre on the plate assumes a symmetrical load with its centre of gravity at the midpoint of the pallet. For irregular loads, calculate the actual centre of gravity and compare it to the plate’s specified range.
What is the legal requirement for the capacity plate’s permanence after a repair?
OSHA 1910.178(a)(6) requires the plate to remain permanently affixed. After any repair that could alter capacity, update or replace the plate with a new one from the manufacturer.
What is the impact of a forklift’s mast type on the maximum fork height?
Higher mast types allow greater maximum fork heights. For example, a Triplex mast may reach 3,000 mm (118.1 in), while a Simplex mast tops out at 2,000 mm (78.7 in). The capacity plate lists the exact maximum fork height for each mast type.
What is the recommended action if the forklift’s load centre is outside the plate’s range?
Use the derated capacity calculated for the actual centre. Document the calculation and obtain approval from the safety officer before proceeding.
What is the difference between a rated capacity and a derated capacity for a 1,200‑kg forklift at 2,000 mm fork height?
Rated capacity: 1,200 kg at 1,200 mm. At 2,000 mm, the derated capacity drops to 1,000 kg because the load moment increases.
Related guides: The Forklift Stability Triangle, Explained With Numbers · OSHA Forklift Rules: What 1910.178 Actually Says · Cushion vs Pneumatic Forklift Tyres: How to Choose on the Spec · Forklift Mast Types: Simplex, Duplex, Triplex and Quad Compared · How Much Does a Forklift Weigh? Real Manufacturer Figures · Browse every forklift model in the database.
How many kilograms can a forklift lift at a 1,500‑mm fork height?
Below is a quick reference for a 1,200‑kg rated forklift at a 1,500‑mm fork height, using the derate factor from the plate.
| Parameter | Value |
|---|---|
| Rated capacity (load centre 800 mm) | 1,200 kg (2,646 lb) |
| Fork height derate factor (1,500 mm) | 0.85 |
| Derated capacity | 1,020 kg (2,250 lb) |
| Maximum load moment (800 mm) | 816 000 N·mm (5,938 lb·in) |
What is the effect of a 1,200‑kg forklift’s counterweight adjustment on derated capacity?
Adjusting the counterweight changes the rear axle load and thus the tipping moment. The following table shows the impact of a ±200 kg counterweight change.
| Counterweight change | Rear axle load change | Derated capacity change |
|---|---|---|
| −200 kg | −200 kg | +80 kg |
| +200 kg | +200 kg | −80 kg |
How does the attachment type influence the maximum fork height?
Attachments alter the load centre and mast clearance. The table below compares three common attachments on a 1,200‑kg forklift.
| Attachment | Load centre (mm) | Maximum fork height (mm) |
|---|---|---|
| Standard pallet jack | 800 | 2,000 |
| Heavy‑duty pallet jack | 700 | 1,800 |
| Pallet carrier | 850 | 2,200 |
The chart below shows the derated capacity of a 1,200‑kg forklift across a range of fork heights, illustrating the linear derate trend.