It is well known that the strength characteristics of the glass used for the cathode ray tubes usually has a distinct scatter under the influence of surface flaws. Therefore, it is important to consider the variations in the static and delayed fracture strength of glass for the reliable design of vacuum cathode ray tubes under the atmospheric pressure. In this study, static and delayed fracture strength tests of glass were carried out using polished, abraded and scratched surface specimens in atmosphere in order to investigate the influence of the surface conditions on the strength characteristics statistically. From the goodness of fit test by the chi-square (x2) methed, the validity of the assumed distribution of the cumulative failure probability on the static and delayed fracture strength corresponding to each surface condition are discussed. Moreover, the statistical properties of the relationships between the static and delayed strengths are examined.
