When the inspection unit accepts the entrusted inspection task, it must fill in the entrustment form, and the witness shall produce the witness certificate and sign the inspection entrustment form.

Testing units must implement a password management system.

Number of witness samples:

For test blocks, test pieces and materials related to structural safety, the proportion of witness sampling and sample delivery shall not be less than 30% of the number of samples required by relevant technical standards.

Extended data:

Precautions for inspection:

1. When sampling and making samples at the site, the sampling personnel of the construction enterprise must have witnesses present, and monitor the samples, and take effective measures to seal the samples together with the inspectors entrusted for inspection, or send the samples to the testing unit.

2, cement comes into play, should check the cement factory certificate, production date, quantity, batch number and grade, timely request the construction unit sampling inspection. On-site supervision shall require the construction unit to issue a three-day strength report for each batch of cement. After the report is qualified, the batch of cement can be used for construction.

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