Commercial Gas Leak Detection
Cape Town

LPG has an odorant added to it specifically so that leaks are detectable by smell long before the concentration becomes dangerous. If your staff can smell gas, the correct assumption is that there is a leak until testing proves otherwise — not that someone left a burner slightly open.

Below: the tests used to investigate and confirm a leak, where leaks typically originate, and what happens once one is found.

Signs of a Commercial LPG Leak

• The distinctive smell of gas, particularly near the storage, at the manifold or around appliance connections
• A hissing sound at a joint, valve, regulator or connector
• Consumption rising without any change in how much you are cooking or producing
• Cylinders emptying faster than the usual pattern
• A tightness test failing to hold pressure during an inspection
• Gas detection alarms activating where a fixed system is fitted
• Bubbling in standing water or damp ground over a buried run
• Dead or discoloured vegetation in a line above a buried pipe
• Persistent flame problems that do not resolve when appliances are serviced
• Staff reporting headaches or a smell in a specific area that then disperses

Smell is the most reliable early sign and the one most often talked away. Because LPG is heavier than air, it accumulates in low points — floor level, pits, trenches, cellars, lift shafts and drains — so a smell that seems to come and go may be gas collecting in a low space and dispersing when a door opens.

How Commercial Gas Leaks Are Detected

Leak investigation is a process of narrowing down, not a single test:

1. 1Make the area safe. Isolate, ventilate, and confirm there is no immediate hazard before any testing begins.
2. 2Tightness test the installation. The system is isolated, brought to test pressure and monitored. A gauge that holds steady means no detectable leak. A falling gauge confirms one exists and gives an indication of scale.
3. 3Test in sections. Isolation valves are used to split the installation and each section tested separately, which localises the leak to a length of pipe rather than the whole system.
4. 4Survey with an electronic detector. A gas detector is worked along the identified section, over joints, fittings, valves and connections, and into low points where gas may be collecting.
5. 5Confirm with leak detection fluid. Applied to the suspect joint, it bubbles at the exact point of escape. This is what pinpoints the leak rather than merely locating the area.
6. 6Trace buried sections where the leak is on an underground run, using pipe location and detection at ground level or in bar holes.
7. 7Record and report the location, the likely cause and what is required to repair it.

Never use a flame to look for a gas leak, and do not rely on soap or detergent from the kitchen as a substitute for proper leak detection fluid.

Where Commercial Leaks Usually Originate

• Cylinder connections and pigtails, which are handled at every cylinder change and perish over time
• Manifold joints and non-return valves in the storage compound
• Regulator connections, particularly where a unit has been replaced
• Isolation valve glands and spindles, especially on valves that are rarely operated
• Flexible connectors at appliances, which are the highest-movement part of the system and the most common single source
• Threaded joints made with unsuitable jointing compound or over-tightened
• Corroded external pipework, a persistent issue on Cape Town's coastal sites
• Points of physical damage where pipework has been struck by a trolley, forklift or delivery
• Previous alterations made outside of proper practice
• Buried pipework damaged by later excavation or ground movement

Flexible connectors deserve particular attention in commercial kitchens. Equipment is pulled out for cleaning, the connector is flexed and dragged, and over enough cycles it fails. A restraint that limits how far the appliance can move is the practical fix.

Tightness Testing Explained

Tightness testing is the core diagnostic on any commercial LPG system, and it is worth understanding what the result means. The installation is isolated, brought to a defined test pressure, allowed to stabilise for temperature, then monitored over a set period.

• A stable reading means no leak is detectable at the sensitivity of the test.
• A falling reading means gas is escaping, and the rate of fall indicates roughly how significant it is.
• Stabilisation matters. Gas expands and contracts with temperature, so a test read too soon can show a change that is thermal rather than a leak. This is exactly why a quick five-minute check is not the same as a proper test.

The same test is used to prove new pipework before commissioning, to verify an installation during a Certificate of Conformity inspection, and to confirm a repair afterwards. See commercial gas COC Cape Town for how it fits into certification.

Fixed Gas Detection Systems

Where a commercial site wants continuous monitoring rather than periodic testing, fixed detection provides it. Detector heads sense gas in the atmosphere and signal a control panel, which can raise an alarm and operate a solenoid valve to cut the supply automatically.

• Head positioning is critical. LPG is heavier than air, so heads mount at low level. A detector mounted near the ceiling will not respond to an LPG leak in time to be useful.
• Coverage should include the storage compound, the areas where appliances are concentrated, and any low points where gas could collect.
• The solenoid valve is what actually stops the gas, and it needs to be positioned where isolating it protects the area being monitored.
• Regular functional testing is essential. A detection system that has never been tested since installation cannot be relied on.
• Alarm response needs to be a documented procedure your staff know, not just a noise.

Detection complements periodic tightness testing rather than replacing it, because detection finds gas that is already escaping into the space while tightness testing finds leaks before they become significant.

After the Leak Is Found

Once located, the repair depends on what failed: replacing a perished pigtail or flexible connector, remaking a threaded joint properly, replacing a leaking valve or regulator, cutting out and replacing a corroded or damaged section, or excavating and repairing a buried run.

Whatever the repair, the sequence afterwards is the same: re-test the section, then re-test the full installation, then return it to service and confirm working pressure at the appliances. Where the repair altered the installation, it also needs certifying again. If leaks keep appearing at different points, the underlying issue is usually the age or condition of the system as a whole rather than a series of unrelated failures, and a broader assessment is the sensible next step — see commercial gas repairs in Cape Town.

Commercial Gas Leak Detection Costs in Cape Town

After the Leak Investigation

Suspect a leak on your commercial installation? Get quotes from commercial gas installers in Cape Town — and if you can smell gas now, isolate, ventilate and call from outside the building rather than waiting.

Commercial Gas Leak Detection FAQs