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STEELTOETOOLS

Construction & Safety Calculators

26 free tools

Instant, sourced calculators for materials, rigging and occupational safety. US customary units by default, metric one tap away. Every formula is documented and cited on the page.

Paving & Earthwork

Asphalt Tonnage Calculator
Tons of hot mix from your area, compacted thickness and the Gmb on your mix design.
Gravel Calculator
Tons and loose cubic yards to order for a driveway, pad or trench — compaction included.

Concrete & Masonry

Concrete Bag Calculator (40, 60, 80 lb)
How many 40/60/80 lb bags for your pour — from the manufacturer's yield, not a guess.
Concrete Column & Pier Calculator
Round or rectangular columns and piers — volume, bags, weight and cost, one column or fifty.
Concrete Footing Calculator
Cubic yards, bags and cost for continuous or pad footings — from the dimensions on your plan.
Concrete Slab Calculator
Cubic yards, bag counts and cost for a slab, pad or footing — waste allowance included.
Fence Post Concrete Calculator
Bags per post and for the whole fence, from the hole you are actually digging.

Conversions

Cubic Yards to Tons Converter
Yards to tons and back, with a sourced density per material instead of one made-up factor.

Recordkeeping & Safety Metrics

DART Rate Calculator
Columns H and I of your OSHA 300A, plus hours worked — the rate OSHA targets inspections on.
Injury Cost Estimator
Claim cost in, true cost out — with the extra sales it takes to pay for it.
OSHA 300A Summary Helper
Total the 300A columns, catch the classic mistakes, and read your three rates off the same numbers.
Severity Rate & Lost Time Rate Calculator
Days away and days of restriction, per 100 workers — plus the lost time case rate and days per case.
TRIR Calculator
Recordable cases and hours worked in, TRIR out — using the four case columns of the OSHA 300A summary.

Fall Protection

Fall Clearance Calculator
Enter your anchorage, lanyard and the clearance you actually have. The calculator tells you whether a fall would be arrested above the lower level.

Rigging & Lifting

Forklift Load Center & Capacity Calculator
A longer load center means less capacity. This runs the load-moment arithmetic of 1910.178 Appendix A.
Load Weight Estimator (Material & Shape)
Weight of a load from its shape and material — the step before any sling calculation.
Rigging Sling Tension Calculator
Tension per leg from load, angle and number of legs — and why a 30° angle doubles it.
Sling D/d Ratio Calculator
Divide the bend diameter by the rope diameter — and see whether your sling's rated load still stands.

Noise

Hearing Protector NRR Derating Calculator
What noise level reaches the ear? Derate the NRR the way OSHA and NIOSH do.
Noise Exposure TWA Calculator (OSHA & NIOSH)
8-hour TWA and dose from levels and durations — OSHA and NIOSH side by side.

Heat & Cold Stress

Heat Index & Work/Rest Schedule Calculator
Heat index, NWS risk category and the OSHA heat-trigger actions for today's shift.

Ergonomics

NIOSH Lifting Equation Calculator
RWL and Lifting Index from the Revised NIOSH Lifting Equation, with every multiplier shown.

Industrial Hygiene

Respirator APF & Maximum Use Concentration Calculator
APF from OSHA Table 1, MUC = APF x the exposure limit, and the minimum APF your exposure needs.
Silica Table 1 Task Lookup
The 18 Table 1 tasks, their specified controls and the required APF — with the total-shift four-hour rule applied.

Excavation & Trenching

Soil Type Classification Helper (A, B, C)
Answer the Appendix A questions and see which clause drives Type A, Type B or Type C — and what still has to be tested.
Trench Slope & Excavation Calculator
Slope, cut-back distance, top width and volume by OSHA soil type — with the 4 ft, 5 ft and 20 ft thresholds.