Compliant with IGEM/UP/1B Edition 4

Precision gas
tightness testing. Simplified.

The professional toolkit for UK gas engineers. Calculate installation volume, permissible pressure drop and purge volume — then export a full audit-trail PDF, all to the current IGEM/UP/1B Edition 4 standard.

Accounts are created by an administrator

What it does

Everything a tightness test needs, in one place.

Enter the pipework, meter and observed pressure drop. The calculator handles the standard, the maths, and the paperwork.

01 / IV

Installation Volume

Sum pipework runs across common copper and steel sizes (8mm to 2"), add meter and other volumes, get IV in m³ instantly.

02 / ΔP

Permissible pressure drop

Pass/fail verdicts for Natural Gas, LPG and LPG/Air using the Edition 4 permissible-limits tables — no lookup required.

03 / MOVE

Perceptible gauge movement

Automatic 0.25 mbar / 0.2 mbar threshold based on your gauge type (water, 1-dp or 2-dp electronic).

04 / PV

Purge volume & time

PV = 1.5 × IV, plus purge time estimates using the meter's gas rate — ready for your on-site record.

05 / PDF

Audit-trail PDF

One-click report including engineer, business, job ID, client, site, signature, entered inputs and SI conversions.

06 / CLOUD

Cloud records

Every generated PDF and test record is saved to your private account — searchable and available across devices.

07 / SCAN

QR / barcode capture

Scan meter serial numbers with your phone camera to eliminate typing errors on the audit trail.

08 / GUIDE

Step-by-step wizard

Optional guided mode walks you through the IGEM/UP/1B procedure with clause references at every step.

09 / PWA

Offline & installable

Install to your phone or desktop home screen and keep working on-site without an internet connection.

The calculations

What the app works out for you.

Three core checks sit behind every tightness test. Here is what each one means in plain language.

IV

Installation Volume

The total volume of gas contained in the pipework and meter you are testing. The app adds up each pipe run, the meter volume and any extra fittings, then converts everything into cubic metres (m³). This figure drives the rest of the test.

IV = pipework volume + meter volume + other volumes

ΔP

Permissible pressure drop

How much the pressure is allowed to fall during the test. The app compares your observed pressure drop against the Edition 4 limits for the fuel gas and installation volume. It then gives a clear PASS or FAIL verdict.

PASS if observed drop ≤ permissible limit

PV

Purge Volume

The minimum volume of inert gas or fresh air needed to clear the installation safely before re-commissioning. The app uses the standard multiplier and your IV to calculate it, plus an estimated purge time based on the meter gas rate.

PV = 1.5 × IV

Ready to run your first test?

Sign in with the credentials your administrator issued you.