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Free Workplace Safety & WHS

Free WHS calculators: LTIFR, TRIFR, noise exposure, NIOSH lifting, fall clearance, WBGT and risk matrix — all browser-based. No data uploaded, no sign-up. Calculations follow NIOSH, ISO, ACGIH, AS/NZS, and ANSI/ASSP standards, covering Australian, New Zealand, UK, and US workplaces. Always supplement online calculations with on-site measurement by a competent person.

8 tools available

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All Workplace Safety & WHS (8)

LTIFR Calculator

Calculate Lost Time Injury Frequency Rate (LTIFR). Enter injuries and hours worked. Supports AU/UK ×1M and OSHA ×200K bases with severity rate.

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TRIFR Calculator

Calculate Total Recordable Injury Frequency Rate (TRIFR). Covers LTI, MTI, RWI and fatalities. AU/UK and OSHA base rates supported.

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Risk Matrix Calculator

Calculate risk scores with a colour-coded 3×3, 4×4 or 5×5 risk matrix. Based on ISO 31000. Enter likelihood and consequence for risk band and recommended action.

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Daily Noise Exposure Calculator

Calculate daily noise exposure (LEX,8h) and noise dose for multiple tasks. Supports ISO 9612/AS/NZS 1269 (3 dB) and OSHA (5 dB) exchange rates.

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NIOSH Lifting Equation Calculator

Calculate Recommended Weight Limit (RWL) and Lifting Index using the NIOSH Revised Lifting Equation. Metric and imperial. All multipliers: HM, VM, DM, AM, FM, CM.

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Fall Clearance Distance Calculator

Calculate total fall clearance distance for shock-absorbing lanyards and self-retracting lifelines. Includes FFD, deceleration distance, body suspension and safety factor.

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WBGT Heat Stress Calculator

Calculate Wet Bulb Globe Temperature (WBGT) and heat stress risk. ACGIH TLV action limits with work/rest schedule. Acclimatized and clothing adjustments.

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Blood Alcohol (BAC) Calculator

Estimate Blood Alcohol Content using the Widmark formula. Enter drinks, weight and time. Shows BAC vs AU/US/UK legal limits. For WHS training purposes only.

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Frequently Asked Questions

Are these WHS calculators free?
Yes. All workplace safety and WHS calculators on Stax are completely free with no sign-up, no usage limits, and no premium tier.
Are my inputs sent to a server?
No. All calculations run entirely in your browser. Injury counts, noise levels, personal measurements, and all other inputs never leave your device.
Which safety standards do these calculators follow?
Calculators follow published standards: NIOSH Revised Lifting Equation (1994), ISO 9612 and AS/NZS 1269 for noise, ACGIH TLV for heat stress (ISO 7243), ANSI/ASSP Z359 and AS/NZS 1891 for fall clearance, Widmark formula for BAC, and ISO 31000 for risk matrix. Each tool cites its reference standard.
Can I use these results for legal or compliance reporting?
These tools are planning aids and educational calculators — not certified compliance instruments. LTIFR and TRIFR results can support internal reporting, but statutory reporting to regulators should be verified with your WHS management system and a qualified safety professional.
Which safety calculators are available?
Phase 1 includes LTIFR, TRIFR, Risk Matrix (3×3/4×4/5×5), Daily Noise Exposure (LEX,8h / ISO and OSHA), NIOSH Lifting Equation (RWL and Lifting Index), Fall Clearance Distance (lanyard and SRL), WBGT Heat Stress (instrument and simplified modes), and Blood Alcohol Content (Widmark formula).