New Septic Tank Manhole Safety Device Could Save Lives

31 August 2017 by Daryl Tunningley

Independent waste management group CSG, whose business includes a major off-mains drainage maintenance operation, plans to deploy a new “potentially life-saving” device specifically designed to prevent falls into open septic tank manholes.

The Manhole Safety Barrier (MSB) has been devised in-house by the company’s health & safety manager Kevin Mooney who said early trials of the device carried out by CSG operatives had produced “a very positive response.”

It reduces the opening size of a manhole and minimises the risk of an operator being able to fall through to the bottom of the pit. But the barrier still allows unimpeded access for emptying and clearing equipment like vacuum pumps. 

The barrier consists of one fixed position tube and two which are hinged and allow the frame to form a cross shape which is designed to be securely locked into position from corner to corner of the manhole. It takes only minutes to assemble. 

Septic tank clearance is one of CSG’s core activities. Each year, the company’s 45 specialist drivers carry out around 55,000 tank clearances, sometimes in remote rural areas where the operatives usually work unaccompanied, often when the customer is not at home. 

Operatives have to stand over the open pit and have an unobstructed view of the operation during the emptying or jetting process.

“Working over open manholes means there is the potential for the operator to fall into the pit. Many of these pits are deep and with an oxygen depleted atmosphere. There is also the possibility of hitting your head during the fall, and there is rarely a means to climb out, so a device like this can potentially safe lives,” said Mr Mooney who designed and built the prototype himself.  

Mr Mooney said it was not practical to remove the risk entirely, but it was essential to minimise the potential of a fall into these openings, particularly when there were site hazards such as lifted manhole covers, slippery conditions and even hoses which could cause trips. 

Accidents of this kind were very rare and CSG had never experienced one, he said. But there had been a number of fatal septic tanks falls reported from around the world. “But effective health and safety programmes are not just about responding to known accident statistics. It’s just as important to anticipate potential problems and devise the methods to prevent them before they happen.

“What you have to look at is the potential consequences of this kind of accident which could be fatal. We’d prefer to protect our staff now rather than wait for an accident.”

Fareham-based CSG has had the device independently load tested and certified by independent experts SWL Rope Lifting & Testing Ltd. and now plans to produce a full user guide for drivers and arrange manufacture of the device which will then be included as standard equipment on all its of vacuum tankers.

Image Caption: CSG health & safety expert Kevin Mooney demonstrates the new manhole safety device he designed to prevent septic tank accidents.