# Inspection Sampling ## Designing a chip inspection Inspectors check chips against an inventory of their identities and locations. A sample can reveal missing or misidentified chips; how much it establishes depends on the size of the discrepancy and the access inspectors receive. ### Hypothetical inventory 7,200 listed chips; at least 25 discrepancies; 10 chips off limits. Listed chipsMissing or misidentified chipsAt leastChips off limits 10 of the 25 discrepancies could be among the chips off limits, leaving at least **15** in the accessible inventory. Chance sought (%) Minimum sample for 90% 1,023 chips 633 with unrestricted access Use this sample 91.7% chance of selecting at least one missing or misidentified chip when 1,100 of 7,190 accessible chips are checked Chance of selecting a discrepancy Chips inspected 10 chips off limitsUnrestricted access90% target Chips inspected 1,100 Exact sample size At this sample size, more than **11 chips off limits** would put the chance below 90%. Chips are sampled uniformly at random without replacement. The calculation puts as many discrepancies as possible among the chips off limits; a sampled discrepancy still has to be recognised by the inspector. Equipment omitted from the inventory is outside this calculation. ### Who can authorise an inspection? MIRI’s draft draws on the Chemical Weapons Convention, but changes the vote required to launch a challenge inspection. In the proposed US–China Council, either country could withhold consent to an inspection of itself. [MIRI draft agreement Proposed · version 3](https://arxiv.org/html/2511.10783v3)[Chemical Weapons Convention Treaty · Article IX](https://www.opcw.org/chemical-weapons-convention/articles/article-ix-consultations-cooperation-and-fact-finding) #### Approval The Executive Council must agree by consensus. It initially consists of the US and China. (X.3(b); III.3) Preparations begin on a valid request. Stopping them takes three quarters of the Council; the requesting and inspected states cannot participate in that decision. (IX.14–17) #### Time to act The host must grant access within 24 hours of the Council calling the inspection. Surveillance is permitted during that interval. (X.3(c)) The Council has 12 hours to reject a request as frivolous, abusive or outside the Convention’s scope. Its deliberations cannot delay the inspection. (IX.16–17) #### Who receives the findings The technical body supplies the US and China with all information it receives or generates, including inspection results. (X.4(b)) All States Parties receive the final report, including the inspectors’ assessment of access and cooperation. (IX.21) The draft also requires both parties to approve the inspection team and caps challenge inspections in any one Party’s territory at 20 a year, changeable by Council consensus (X.3(d–e)). The CWC’s managed-access provisions appear in Part X of its Verification Annex.