A MAN falsified documents instead of checking gas equipment had been installed correctly.
Self-employed Andrew Church, of Ensign Drive, Gosport, pleaded guilty to a breach of the Health and Safety at Work Act 1974.
It comes as a Health & Safety Executive (HSE) investigation led to the prosecution of Church, along with DSI Plumbing & Heating, and another self-employed man Robert Percival.
The HSE investigated equipment installed in 400 homes in Poole and Reading.
Inspectors found gas leaks, and flues and gas supply pipes that had not been properly fitted.
At Bournemouth Crown Court, Church pleaded guilty to making false entries after he completed the commissioning documents without carrying out the required checks.
Percival, of Legion Road, Poole, pleaded guilty to a breach of the 1974 act for commissioning of gas installations at one property.
They were both given a two-year conditional discharge and each ordered to pay costs of £250.
DSI Plumbing & Heating Ltd, of The Square, Fawley, pleaded guilty to two breaches of the act and was fined a total of £10,000 and ordered to pay a further £1,000 in costs.
HSE head of operations Harvey Wild said: ‘These serious failings involving gas safety only came to light after residents started to complain about ill-health.
‘It is fortunate that in this case, no-one suffered long term ill-effects but the consequences of the faults, if left undetected, could have been fatal.’
The investigation revealed evidence of defects in the installations in 309 of the homes in Harbour Reach, Poole.
There were also defects in the gas installation at 40 homes in Caversham Road, in Reading.