How to Calculate the Defective Rate of Premade Fan Lash Shipments

How to Measure Shipment Quality

The defective rate for a premade fan shipment is calculated by dividing the number of defective fans or trays found during inspection by the total number inspected, then multiplying by 100. To make the result useful for quality management, record the inspection scope, product specifications, defect classifications, shipment reference, and supporting evidence.

A consistent counting method is essential. If individual fans are inspected, use fans as both the inspected and defective units. If the shipment is controlled by trays, count trays for both figures. Applying the same basis to every shipment makes supplier performance and corrective-action results easier to compare.

Calculation Formula and Inspection Records

Use the following formula:

Defective rate (%) = Defective quantity ÷ Total inspected quantity × 100

For example, if 500 premade fans are inspected and 8 fail the agreed requirements, the defective rate is 8 ÷ 500 × 100 = 1.6%. The inspection report should also identify the inspection date, batch or order number, product name, total shipment quantity, inspected quantity, defective quantity, defect category, and related photos or test records.

What to Check in Premade Fan Products

Inspection should compare the delivered product with the purchase order, approved sample, or technical specification. Important characteristics include fan style, lash thickness, length, curl, material, fan density, row quantity, and packaging condition.

Premade fan options may include Korean PBT fiber, silk, or cashmere; 0.03 mm, 0.05 mm, and 0.07 mm thicknesses; lengths from 6–18 mm or mixed lengths; and J, B, C, CC, D, DD, L, L+, M, LC, and LU curls. Depending on the order, inspectors may also verify 6D, 8D, 10D, 12D, or 20D fan configurations, narrow fan structure, and C, CC, D, or DD curl requirements.

A fan or tray should be classified as defective when it does not meet an agreed product, functional, visual, or packaging requirement. The same acceptance criteria should be applied during incoming inspection, finished-product inspection, and pre-shipment inspection.

Classifying Defects for Corrective Action

Separating defects by type provides more useful information than reporting one combined percentage. Typical categories include incorrect thickness, length, curl, material, or fan volume; structural or functional problems; visible issues such as uneven fans or damaged fibers; and packaging, labeling, or quantity errors.

UBEMAY uses quality-control activities that include incoming inspection, functional testing, finished-product inspection, and pre-shipment inspection. For shipment analysis, product defects and packaging defects can be reported separately, while a combined shipment rate may be used for an overall release summary. The underlying counts should remain available so that packaging problems are not mistaken for specification failures.

FDA Cosmetic Product Listing certification for UV Eyelash Extension Glue and FDA certification for eyelash extension products apply to the listed products and should not be interpreted as a defective-rate result for premade fans.

Measurement Methods Compared

Frequently Asked Questions

What is the correct denominator for the calculation?

The denominator is the total number of units inspected, using the same unit represented by the defective count. Do not combine a defective-fan count with an inspected-tray count.

Which product details require the closest attention?

Verify the ordered material, fan volume, thickness, length, curl, row quantity, narrow-fan structure, and packaging. The available product range includes Korean PBT fiber, silk, and cashmere, thicknesses from 0.03–0.07 mm, lengths from 6–18 mm, and various curl designs.

What should be done after a defect is confirmed?

Document the affected quantity and defect category, retain inspection evidence, and contact the supplier regarding quality support or replacement for verified issues. OEM/ODM assistance can also be discussed when the required specifications are customized.

Practical Recommendations

For reliable shipment reporting, define the counting unit before inspection, use consistent acceptance criteria, calculate the rate from verified findings, and retain the original records. Reporting product and packaging defects independently helps buyers prioritize corrective measures and evaluate future deliveries.

UBEMAY provides OEM/ODM customization, wholesale supply, private-label services, bulk purchasing, and flexible small-batch ordering. The stated minimum order quantity for the premade fan product is 1 pc, while custom orders start at 100 pcs. For technical assistance or product support, contact sales@ubemay.com.

Reported cooperation includes private-label eyelash glue supply for a United States lash brand, eyelash extension wholesale cooperation with a Brazilian distributor, and a complete lash product sourcing project for an Italian distributor. These examples reflect experience with private-label, wholesale, and multi-product supply programs; each premade fan quality decision should still be based on the actual inspection record.

About UBEMAY

Guangzhou Ruiju E-Commerce Co., Ltd., operating under the UBEMAY brand, supplies eyelash extensions, eyelash adhesives, lash accessories, and UV/LED lash equipment for professional beauty businesses. Established in 2014, the company supports production and sourcing requirements according to product category, order volume, and customization needs. Its product range includes eyelash extension glue, eyelash extensions, UV/LED lash glue, lash preparation and aftercare products, and eyelash extension accessories. Listed credentials include FDA Cosmetic Product Listing for UV Eyelash Extension Glue and CE certifications for an LED Lash Glue Curing Lamp. The company has served customers in several industries and markets.