Difficulties arising from the poor compatibility of some blood bag and transfusion set combinations remain a significant, ongoing patient safety issue. Proposed changes to international standards based on previously published findings provide a potential resolution when adopted by manufacturers. The aims and objectives of this study were to demonstrate that changes to ISO 3826-1 and 1135-4, especially surface treatment of the transfusion set spike (siliconisation) to reduce insertion force and accidental spiking will not result in: 'Pre-piercing' of the port membrane; difficulty in inserting the spike; leakage from the spike/port connection or unintentional removal of the spike during transfusion. The performance of connections (ports from five and siliconized spikes from two manufacturers) was assessed by a range of physical tests including: pressure tests for leakage at 50 kPa (1.5 bar); static stress (pull) tests at 15 and 20 N. Spike insertion force tests were repeated to challenge original findings. Of the 280 connections tested, there was one dubious pressure tests fail (<10 microL), no pull test failures at 15 N and one at 20 N. Spike insertion forces were acceptable and consistently low with ports from all manufacturers. Findings confirm the benefits of siliconized spikes in improving compatibility between transfusion sets and blood bags. This study does not indicate that the evaluated spikes would be subject to unintentional removal or leakage when used in accordance with manufacturer's instructions. Pressure and pull tests on spike/port connections are a valuable addition to ISO 3826-1 and 1135-4 for manufacturing design validation and quality control purposes.