Abstract
The results of IAPSO Standard Seawater(SSW) comparisons are presented for batches P 70, P 88, P 94, and 13 batches made in 1990's. Except for batches P 70, P 88, P 114 and P 128, the standard deviation (1σ) calculated from the repeated measurements of the same batch of SSW ranges from 0.1×10-3 to 0.3×10-3 in Practical Salinity Scale (PSS) and the difference between label-derived and measured salinity referred to batch P 124 ranged from -1.1×10-3 to 0.9×10-3. The result is consistent with the recent results found in other laboratories. The standard deviations of batches P 70 and P 88 were quite large probably because of the aging effect. The standard deviation of batch P 114 was twice to three times as large as other recent batches without any obvious reason. As for batch P 128, the standard deviation and the difference between label-derived and measured salinity referred to batch P 124 changed remarkably during two years.
