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Guardrail System Fall-Protection Compliance Checker

Check a guardrail system's top rail height and rated load capacities against the fixed requirements of OSHA 29 CFR 1926.502(b).

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The measured height of the guardrail's top edge above the walking/working surface.

OSHA 29 CFR 1926.502(b)(1) requires the top edge height to be 42 inches (1.1 m) plus or minus 3 inches (8 cm) above the walking/working level — i.e. 39 to 45 inches. Measure to the actual top edge of the installed rail.

The manufacturer-rated (or engineered) load capacity of the top rail.

OSHA 29 CFR 1926.502(b)(3) requires the top rail to withstand at least 200 lbf (890 N) applied within 2 inches of the top edge, in any outward or downward direction, without failing.

The manufacturer-rated (or engineered) load capacity of the midrail or other structural member.

OSHA 29 CFR 1926.502(b)(5) requires midrails, screens, mesh, intermediate vertical members, or equivalent structural members to withstand at least 150 lbf (666 N) applied in any downward or outward direction.

Top rail height

42 in

ComparisonA comparison, not a check — no result here is an approval.

Measured against the three fixed figures in OSHA 29 CFR 1926.502(b), which this page restates and does not interpret. The top rail height entered is inside the 39–45 in (991–1,143 mm) the rule fixes. The top rail's rated load is at or above the 200 lbf (890 N) minimum, and the midrail's is at or above the 150 lbf (666 N) minimum. Post spacing and anchorage, screening between the top rail and the walking surface, and the 21-inch wall exemption are not examined here. Matching the figures quoted is not compliance. The rest of the requirement, and the installed work, are outside what this page can see.

Top rail rated load capacity
200 lbf (OSHA min 200)
Midrail rated load capacity
150 lbf (OSHA min 150)
Then change the inputs to see how far the answer moves.

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How this was calculated

Formula source(s)

  • OSHA 29 CFR 1926.502(b) Guardrail Systems (verified against the regulatory text): top edge height must be '42 inches (1.1 m) plus or minus 3 inches (8 cm) above the walking/working level' (i.e. 39-45 inches); midrails installed 'at a height midway between the top edge of the guardrail system and the walking/working level'; top rails must withstand 'at least 200 pounds (890 N) applied within 2 inches of the top edge'; midrails and structural members must withstand 'at least 150 pounds (666 N) applied in any downward or outward direction'; midrails, screens, mesh or equivalent members must be installed 'when there is no wall or parapet wall at least 21 inches (53 cm) high' — the wall is what removes the requirement, not what creates it. These are FIXED regulatory values (a performance standard restated directly, not an engineering estimate).

Inputs used

Top Rail Height Above Walking/Working Surface
42 in
Top Rail Manufacturer-Rated Load Capacity (OSHA minimum 200 lbf / 890 N)
200 lbf
Midrail Manufacturer-Rated Load Capacity (OSHA minimum 150 lbf / 666 N)
150 lbf

Intermediate steps

Top rail rated load capacity
200 lbf (OSHA min 200)
Midrail rated load capacity
150 lbf (OSHA min 150)
Final result42 in

Confidence note: Measured against the three fixed figures in OSHA 29 CFR 1926.502(b), which this page restates and does not interpret. The top rail height entered is inside the 39–45 in (991–1,143 mm) the rule fixes. The top rail's rated load is at or above the 200 lbf (890 N) minimum, and the midrail's is at or above the 150 lbf (666 N) minimum. Post spacing and anchorage, screening between the top rail and the walking surface, and the 21-inch wall exemption are not examined here. Matching the figures quoted is not compliance. The rest of the requirement, and the installed work, are outside what this page can see.

What this calculation does not cover

  • The height check reads the rail standing still. OSHA also requires that when the 200 lbf load is applied downward, the top edge must not deflect below 39 inches — 1926.502(b)(4) — so a rail installed at 39 or 40 inches passes the height test here and fails the standard the moment somebody leans on it. Height and stiffness are one requirement together, and only the height half is checked above.
  • Only the midrail's rated LOAD is compared; its height is not. The rule puts the midrail midway between the top edge and the walking surface — roughly 21 inches under a 42-inch rail — and a midrail sitting low leaves an opening a body can pass through while both load figures on this page sit inside the values they are compared with.
  • Nothing above looks at what the rail is made of. OSHA bars steel banding and plastic banding as top rails or midrails outright, sets a quarter-inch minimum nominal diameter or thickness, requires wire-rope top rails to be flagged at intervals no greater than 6 feet, and requires the surface to be finished so it cannot cut a hand or snag clothing. A rail can carry 200 lbf and still be non-compliant on any one of those.

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This result is a specification — 42 in — not a quantity. Put the thing it sizes into your project: how many, what you call it, and your supplier’s price.

3.5 ft
Schematic, drawn to the proportions you entered — not to scale on screen.

Computed in your browser — nothing you enter is uploaded. Presented in US customary units and US trade terminology. Where a formula follows a published standard, that standard and its edition are cited beside it on this page; where none governs, the page says so. Local amendments override model codes — verify against the code in force where you build.

Sources checked 2026-09-06 · in the site-wide review of 2026-09-06 · v1.0.1

Regulatory standards & verification citations1
  1. OSHA 29 CFR 1926.502(b) Guardrail Systems (verified against the regulatory text): top edge height must be '42 inches (1.1 m) plus or minus 3 inches (8 cm) above the walking/working level' (i.e. 39-45 inches); midrails installed 'at a height midway between the top edge of the guardrail system and the walking/working level'; top rails must withstand 'at least 200 pounds (890 N) applied within 2 inches of the top edge'; midrails and structural members must withstand 'at least 150 pounds (666 N) applied in any downward or outward direction'; midrails, screens, mesh or equivalent members must be installed 'when there is no wall or parapet wall at least 21 inches (53 cm) high' — the wall is what removes the requirement, not what creates it. These are FIXED regulatory values (a performance standard restated directly, not an engineering estimate).
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Called something else where you work? Guard and handrail — the term in each market, how close the equivalence really is, and the standard that governs it.

How to calculate guardrail system fall-protection compliance checker in 4 steps

  1. Top Rail Height Above Walking/Working SurfaceThe measured height of the guardrail's top edge above the walking/working surface.
  2. Top Rail Manufacturer-Rated Load Capacity (OSHA minimum 200 lbf / 890 N)The manufacturer-rated (or engineered) load capacity of the top rail.
  3. Midrail Manufacturer-Rated Load Capacity (OSHA minimum 150 lbf / 666 N)The manufacturer-rated (or engineered) load capacity of the midrail or other structural member.
  4. Top rail heightThe tool computes the top rail height from those figures and shows the formula, its sources, and a confidence rating alongside it.

Frequently asked questions

What top rail height does OSHA require for a guardrail system?
29 CFR 1926.502(b)(1) requires the top edge to be 42 inches (1.1 m) above the walking/working surface, plus or minus 3 inches — so any height from 39 to 45 inches complies.
What load must the top rail and midrail withstand?
Per 1926.502(b)(3), the top rail must withstand at least 200 lbf (890 N) applied within 2 inches of the top edge. Per 1926.502(b)(5), midrails and other structural members must withstand at least 150 lbf (666 N) applied in any downward or outward direction. Both are manufacturer-rated or engineered values you supply — this checker only compares them to the OSHA minimums.
Does a passing result mean my guardrail system is fully OSHA-compliant?
No. This restates the fixed requirements of OSHA 29 CFR 1926.502(b) only — it does not check post spacing/anchorage, screen/mesh requirements between the top rail and walking surface, the 21-inch wall/parapet exemption, or overall system installation quality. A competent person must verify the complete installed system.
Preliminary estimate, not certified engineering. This tool produces an indicative quantity calculation for planning purposes only — it is not a certified structural analysis, a guaranteed material takeoff, or a substitute for building department approval. Always verify measurements on-site and have a licensed contractor or structural engineer review any load-bearing, code-sensitive, or safety-critical work before purchasing materials or starting construction. Spotted an arithmetic or standards error? Report it to contact@craftquantities.com with your inputs — a confirmed fix gets a permanent check of its own, so the same mistake cannot come back.