The London and South East traffic commissioner, Nick Denton, has warned restricted licence holders not to neglect their legal duties when using vehicles fitted with digital tachographs.

The reminder comes after Denton suspended a scaffolding firm for 21 days because of "serious and prolonged drivers’ hours shortcomings".

DVSA examiners reported Park Lane Scaffolding Ltd – and drivers employed by the business – for various infringements, including failing to obtain a company tachograph card and digital download equipment several months after buying a vehicle with a digital tachograph.

Denton said he had seen several cases at public inquiry recently of restricted operator licence holders running digital tachograph vehicles with "no idea how to use them".

Many had also not obtained a company card to download and analyse data relating to their employees’ driving duty.

The Traffic Commissioner criticised the directors of Park Lane Scaffolding Ltd after they failed to get a company card despite being told about the requirement by a DVSA traffic examiner.

His investigation also revealed one driver had worked for 12 consecutive days before taking a weekly rest and that drivers were breaching the regular weekly rest requirement.

A driver was also allowed to use a digital tachograph vehicle without a digital tachograph card.

Denton concluded the firm was not undertaking any analysis of analogue charts either as several obvious centrefield offences had been missed.

The company had previously appeared at a public inquiry in July 2012 for shortcomings that included drivers’ hours oversight.

The licence was suspended for two days on that occasion.

The Traffic Commissioner was given assurances in July 2012 that the director responsible for drivers’ hours was on top of things.

However, at the latest hearing, Denton said that guarantee had proved to be "worthless".

"It is also dispiriting that Mr Papps has today sought to give exactly the same explanation for the continued failings (a recent move to 7.5 tonne vehicles) that he gave in July 2012. This excuse simply does not wash."

Making an order to suspend the company’s licence from February 1 for three weeks, Denton said his previous order had clearly failed to inspire the business to make any effort at all to observe the rules on drivers’ hours and tachographs.

"I consider a much lengthier suspension now to be necessary to bring home to the company the seriousness of the issue of compliance with drivers’ hours and working time rules and to give the company time to get its house in order.

"I came very close to revoking the licence entirely."

During the suspension, vehicles specified on the firm’s licence cannot be used on any other operator’s licence.

Denton also recorded four undertakings on the licence, including that a CPC qualified transport manager would be appointed to advise on, and help ensure, compliance.

Reflecting on other restricted operator cases at public inquiry, the Traffic Commissioner called for a significant improvement in standards.

"It is simply not acceptable for operators to purchase vehicles fitted with digital tachographs and then run them without bothering to find out what the legal requirements relating to digital tachographs are.

"The legal requirements are not a state secret – they are clearly set out on the Government website, and trade bodies such as the RHA and FTA, as well as the trade press, are constantly issuing advice.

"Too many operators seem to be content to get their advice on digital tachographs from a bloke down the pub, rather than DVSA (formerly VOSA) or a trade body.

"Unsurprisingly, that advice turns out all too often to be completely wrong.

"I find it astonishing that licence holders are appearing at public inquiry having been reported for – amongst other things – failing to acquire a company tachograph card or any download software.

"How can an operator seek to prove they are complying with the regulations – and crucially check whether their drivers are working within the drivers’ hours rules – if they can’t download driver or vehicle data?

"Restricted operators need to be alert to these requirements and the potential impact on their licence of failing to meet them.

"The responsibilities involved in holding a licence go rather deeper than just buying a few vehicles to carry equipment for your main business."