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The March 2026 update marks the first major overhaul of small-scale tightness testing and purging in over a decade.

  • Key Date: Published March 25, 2026.

  • The Grace Period: There is a 6-month transition window. Edition 3 and Edition 4 run concurrently until September 30, 2026.

  • Compliance: After September 30, only Edition 4 procedures will be accepted by the Gas Safe Register.

 

This intensive 1 day CPD course is specifically designed for Gas Safe registered engineers to navigate the transition from Edition 3 to the new Edition 4 standards. As the industry moves away from meter based testing toward a more rigorous volume based approach, this session ensures you are fully compliant before the September 30, 2026 deadline.

What’s Covered in the Course:

  • The Transition Blueprint: Understanding the six-month “dual-running” period and the mandatory implementation dates for Gas Safe inspections.

  • Calculating Installation Volume (IV): Comprehensive training on the new requirement to calculate the internal volume of a system (m3) to determine permissible drops, replacing the old meter-size method.

  • The “Zero-Tolerance” Pipework Test: A deep dive into the new requirement to isolate all appliances if any movement is detected. You will learn the procedure to prove that pipework has no perceptible movement independently of connected appliances.

  • Revised Permissible Limit Tables: Step-by-step guidance on using the new standardised tables for Natural Gas, LPG, and LPG/Air, including “automatic pass” thresholds where calculation isn’t required.

  • Standardised Purging (PV = 1.5 x IV): Mastering the updated purging formula that simplifies the process across all small installations, regardless of meter size or pipe diameter.

  • Expanded Scope (LAVs & Caravans): Understanding how Edition 4 now officially encompasses Leisure Accommodation Vehicles and Caravans, including specific testing nuances for these environments.

  • Practical Validation & LDF Testing: Best practices for testing disturbed joints and pipework between isolation valves and appliances using Leak Detection Fluid (LDF) following a successful test.

Who Should Attend?

This course is essential for any engineer working on small Natural Gas or LPG installations (up to 16 m3/h capacity and 2 bar MOP) who needs to update their technical knowledge to meet the latest Industry Standard Update (ISU) 133.

Course Includes:
  • Price:
    £295 +VAT
  • Duration:
    1 day
  • Time:
    8:30am - 3:00pm
  • Schedule:
    In-centre only
  • Payment Plan:
    Not available
  • Enhanced Learner Credits Accepted:
    No
  • Pre-entry Requirements Required:
    No
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