Standard PET Industry 28 Day Test Method

Purpose

This procedure evaluates the performance of PET bottles when they are dipped in a stress agent and then subjected to high temperature and high humidity conditions.

Description

Bottles are carbonated to a predetermined elevated CO2 level and then placed in the 100°F, 85% RH chamber overnight. These bottles are then dipped in a stress crack agent such that the entire base of the bottle is covered with the agent. The bottles are then placed back into the 100°F, 85% RH chamber for a period of 28 days. During this period, bottles are examined daily and all breakers, leakers and pressure loss bottles are recorded and removed from the chamber. At the conclusion of the 28 days, the remaining bottles are removed and checked for pressure to assure that none were missed during the 28 days of the test. A report of the bottle performance is then created.This procedure evaluates the performance of PET bottles when they are dipped in a stress agent and then subjected to high temperature and high humidity conditions.