| Input | Example value | Why it matters |
|---|---|---|
| Workers | 25 | Scales most PPE quantities linearly. |
| Duration | 30 days | Drives replacement sets for consumables. |
| Default wastage | 5% | Covers loss, damage, and sizing variation. |
| Gloves | 4 USD, 2 pairs, 30-day interval | Often the highest recurring line item. |
| Respirator | 1.5 USD, 10 units, 7-day interval | Consumable with frequent replenishment. |
| Contingency | 5% | Buffers urgent resupply and price changes. |
1) Convert duration to days
duration_days = duration_value × factor
Factor is 1 (days), 7 (weeks), or 30.4375 (months average).
2) Replacement sets per item
sets = max(1, ceil(duration_days ÷ replacement_interval_days))
If the interval is 0, the item is issued once (sets = 1).
3) Units required (including wastage)
units_total = workers × qty_per_worker × (1 + wastage% ÷ 100)
4) Line costs
item_cost = units_total × unit_cost × sets
maintenance_cost = units_total × maintenance_cost_per_set × sets
Maintenance can represent cleaning, inspections, or consumables per cycle.
5) Project totals
subtotal = items + maintenance + per_worker_overheads
after_discount = subtotal − (items_and_maintenance × bulk_discount%)
after_tax = (after_discount + shipping) × (1 + tax%)
grand_total = after_tax × (1 + contingency%)
- Enter project basics: workers, duration, and currency label.
- Set planning allowances: wastage, discount, shipping, tax, contingency.
- Review PPE rows: confirm unit cost and quantity per worker.
- Add replacements: use realistic replacement intervals for consumables.
- Optional overheads: include fit-testing, training, and issuance handling.
- Calculate: the result appears under the header, above the form.
- Export: use CSV/PDF buttons to share with procurement.
1) Why PPE budgeting deserves a line-item model
PPE spend is predictable when you treat it like materials. Each worker consumes a known baseline kit, plus a stream of replacements. Many sites see PPE as “miscellaneous,” yet crews of 20–100 can create repeat orders every week. A structured model improves forecasting, reduces emergency purchases, and supports audit-ready documentation.
2) Typical replacement intervals used in practice
Planning intervals vary by task severity and climate. Common starting points are gloves every 15–30 days, safety glasses every 60–90 days, vests every 120–180 days, and hard hats annually unless damaged. Disposable respirators can be weekly or even daily for dusty activities.
3) Wastage percentages that match real sites
Wastage covers loss, damage, theft, and sizing mismatch. For stable sites, 3–5% is often workable. High-turnover labor, night work, or remote logistics can push wastage to 8–12%. This calculator lets you set a default, then override wastage per item for better realism.
4) Quantities per worker and trade-specific kits
Not every worker needs the same PPE. A concrete cutting crew may require hearing protection and respirators continuously, while a finishing crew may consume more gloves and eye protection. Use “Qty / worker” to represent issued units per person, then split trade groups into separate runs to compare their cost profiles.
5) Maintenance and inspection costs you should not ignore
Reusable PPE has hidden cost: cleaning, inspection, and minor parts. A fall harness may require documented inspection cycles, tags, and occasional replacement hardware. Enter a maintenance cost per set to capture those recurring expenses alongside purchase cost, producing a more defensible total.
6) Procurement adjustments: discounts, shipping, and tax
Bulk discounts commonly range from 2–10% for consolidated orders, while last‑minute resupply can add significant shipping. Apply discount on the PPE subtotal, then add shipping and tax to reflect invoice reality. The breakdown helps explain why “cheap” PPE can still generate a high delivered cost.
7) Contingency and sensitivity checks
A contingency of 3–10% is a practical planning band for price swings and urgent replacements. If totals feel high, test sensitivity: reduce wastage by 2%, extend glove intervals from 15 to 30 days, or add a bulk discount. The “per worker-day” metric is useful for comparing projects of different durations.
8) Reporting and handover using exports
Procurement teams need a clean, shareable record. Export CSV for spreadsheets and estimating systems, and PDF for approvals and toolbox briefings. The report includes core assumptions and a “top line items” list, which is helpful when negotiating pricing for the largest contributors.
1) Should I set replacement interval to zero?
Use 0 when an item is issued once for the full job, such as a hard hat for a short project. Consumables should use realistic intervals to avoid underestimating.
2) How do I handle different trades and shift patterns?
Run separate calculations per trade group or shift if PPE usage differs. Compare per worker-day values to see which group drives cost and where controls will help most.
3) What wastage percentage is reasonable?
Start at 5% for typical sites. Increase for high turnover, remote delivery, or frequent damage. Reduce if PPE is tightly controlled with sign-out, storage, and supervision.
4) Why include maintenance cost per set?
Reusable PPE can require cleaning, inspection, and minor consumables. Adding a maintenance value makes budgeting closer to reality and supports documented compliance costs.
5) Does the bulk discount apply to shipping and tax?
No. The discount is applied to the PPE purchase and maintenance subtotal, then shipping and tax are added. This mirrors how many suppliers structure invoices and taxes.
6) How is “per worker-day” useful?
It normalizes cost by both headcount and time. Use it to compare projects with different durations or workforce sizes, and to set internal benchmarks for similar scopes.
7) Can I use the exports for procurement approvals?
Yes. Calculate first, then download CSV for detailed review and PDF for sign-off. The exports capture your assumptions, totals, and highest-cost PPE lines for clarity.