What IGEM/UP/1B Edition 4 means for gas engineers from 1 October 2026
The tightness test every gas engineer runs without thinking changes on 1 October. IGEM/UP/1B Edition 4 swaps the old meter-size limit for one based on calculated Installation Volume, and adds a mandatory retest step that will slow some jobs down. This piece covers what changed, why, and what it means on the tools from day one.