How do you calculate good inspection capacity?

Multiply samples per cycle by available cycles for gross capacity, then multiply by uptime and yield as decimals. Here 10 x 48 = 480 gross, x 0.85 x 0.98 = 399.84 good units.

What is the difference between gross and good capacity?

Gross capacity (480) is what the station could inspect with no losses. Good capacity (399.84) is what survives after 72 units of availability loss and about 8.16 units of reject or rework allowance.

What is a good inspection station uptime?

Well-run QC stations hold 85 to 92% uptime; calibration, gauge changeover and inspector breaks consume the rest. The 85% default is a realistic working number, not a best case.

How does accepted-record yield differ from product quality?

Yield here is the share of inspection records accepted without rework, capturing miskeyed data, retests and documentation errors as much as part defects. At 98% the station loses about 8.16 records to rework in this example.

How do I increase good inspection capacity?

Add cycles, raise samples per cycle, or attack the losses. Improving uptime from 85 to 90% alone would lift good capacity from 399.84 to about 423 units in this example.

Sampling inspection vs 100% inspection for sprinkler parts?

Critical life-safety characteristics often require 100% inspection, while sampling applies to lower-risk attributes per an AQL plan. This tool sizes the station's throughput; your acceptance plan defines what must be inspected.

Fire Suppression, Sprinkler & Safety System Products calculator

Inspection Sample Size Calculator

This calculator sizes how many good, accepted inspection records a fire protection QC station can actually produce, not just the gross number it could theoretically run. Inspecting sprinkler heads, valves, gauges and fittings to UL and FM acceptance criteria takes real station time, and that time is eroded by downtime (calibration, changeover, breaks) and by records that get rejected or reworked. Quality managers and inspection planners use it to confirm a station can clear a lot within an inspection window, or to decide how many cycles or stations they need. The headline good-capacity figure is what you should commit to in a quality plan.

What this calculator does

Estimate accepted inspection sample capacity from samples per inspection cycle, available cycles, inspection uptime, and accepted documentation yield.
Use it when planning QA sample inspections for sprinkler heads, valves, cylinders, alarms, detectors, extinguishers, brackets, or safety-system kits.
It computes good inspection output by multiplying samples per cycle by available cycles for gross capacity, then derating for station uptime and accepted-record yield.

Formula used

Gross inspection sample size = samples inspected per cycle × available inspection cycles
Good capacity = gross capacity × uptime × yield

Inputs explained

Samples inspected per cycle:
Available inspection cycles:
Inspection station uptime:
Accepted inspection record yield:

How to use the result

Use it when planning inspection throughput for a fire protection component lot, sizing a QC shift, or checking whether one station can clear incoming volume.
It assumes uptime and yield are independent and stable; a station with bursty downtime or yield that drifts as inspectors tire will not match the smooth average this model produces.

Current U.S. benchmarks

Manufacturing hourly earnings average $30.27 (BLS, Jun 2026), up 4.4% from a year earlier. Median machinist pay is $28.24/hr (OEWS 2025), with state medians on each state page. Manufacturers have 529k open positions nationally (BLS JOLTS).
U.S. housing starts run at 1,177k per year (Census, May 2026), down 8.7% from a year earlier, the demand driver for building products.

Common questions

How do you calculate good inspection capacity? Multiply samples per cycle by available cycles for gross capacity, then multiply by uptime and yield as decimals. Here 10 x 48 = 480 gross, x 0.85 x 0.98 = 399.84 good units.
What is the difference between gross and good capacity? Gross capacity (480) is what the station could inspect with no losses. Good capacity (399.84) is what survives after 72 units of availability loss and about 8.16 units of reject or rework allowance.
What is a good inspection station uptime? Well-run QC stations hold 85 to 92% uptime; calibration, gauge changeover and inspector breaks consume the rest. The 85% default is a realistic working number, not a best case.
How does accepted-record yield differ from product quality? Yield here is the share of inspection records accepted without rework, capturing miskeyed data, retests and documentation errors as much as part defects. At 98% the station loses about 8.16 records to rework in this example.
How do I increase good inspection capacity? Add cycles, raise samples per cycle, or attack the losses. Improving uptime from 85 to 90% alone would lift good capacity from 399.84 to about 423 units in this example.

Last reviewed 2026-05-12.