Yao Glass use well-proven and widely adopted international standard ISO2859-1 (equivalent of

ANSI/ASQC Z1.4-2008, BS 6001, ABC-105, NFX06 –022, NFX 06-022, DIN 40.080, UNI 48.42) Single

Sampling Plan. General Inspection Level Normal II is usually applied to determine the inspection

sample size for aesthetic and functional check. Special Inspection Level will be applied for safety,

reliability, performance or other special test if whereas applicable.

The inspection level designates the relative amount of inspection. Three inspection levels, I, II and

III, are given in Table A for general use. Unless otherwise specified, level II shall be used. Level I

may be used when less discrimination is needed or level III when greater discrimination is required.

Four additional special levels, S-1, S-2, S-3 and S-4 are also given in Table A and may be used where

relatively small sample sizes are necessary (for example, for some destructive test or

time-consuming test) and larger sampling risks can be tolerated.

Sample sizes are designated by sample size code letters and the corresponding AQL level. Table A

shall be used to find the applicable code letter for the particular lot size, Table B shall be used to

find the sample size based on code letter and the prescribed AQL level.

As default, Yao Glass uses general inspection level II, Acceptable Quality Level (AQL) Not allowed /

2.5 / 4.0 of Critical, Major, Minor defect.

For example, there're 6,000 units to be inspected. As per single sampling level II, AQL: Not allowed

/ 2.5 / 4.0 of Critical / Major / Minor:

According to table A, from quantity 3201 to 10000, the corresponding sample size code letter is "L",

therefore in table B, “L” is corresponding to sample size "200". So the maximum allowed number

of defective unit is as follow: Critical Defect 0; Major Defect 10; Minor Defect: 14. In other words, if

the number of critical defective units is more than 0, or major defective units is more than 10, or

minor defective units is more than 14, the lot has to be rejected.

Defects in Classification Criteria

Defects detected during inspection are classified within 3 categories -"Critical", " Major ",

" Minor"and the normal definitions are:

Critical: Defects which could result in hazardous or unsafe conditions for individuals using or

maintaining the product as well as defects contravening legal regulations.

Major: Functional defects reducing the usability or solidity of the product as well as obvious visual

defects reducing the sales value of the product.

Minor: Defects that are unlikely to reduce the use of the product, but nevertheless may influence

the sale.

For random inspection, the following rules are applied: If the same sample has several defects,

only the most serious defect is counted. In the case of critical defects, the entire shipment must be

rejected as a matter of principle and clients consulted for a decision.