RAMS, or Reliability, Availability, Maintainability and Safety, is a well known acronym in the Rail Industry. Given the importance of Safety to the Industry it is surprising that it comes last in the acronym. Given the importance of Cost pressure, its absence from the Acronym is astonishing. Perhaps Safety, Cost, Reliability, Availability and Maintainability or SCRAM would be a more appropriate acronym for the Industry to adopt.

But that would be to miss the other increasingly important factor which is the impact of our actions on the Environment. Introducing Environment to the acronym would give us Safety, Cost, Reliability, Environment, Availability and Maintainability, or SCREAM.

It is unnecessary to rehearse all the constituents of RAMS as they are well known. However Cost and the Environment are factors which respectively are attributed much or little weight in the evaluation and acquisition of new equipment. 

Cost is a given. Cost reduction, Cost down, Stretch 30, Code 30, Cost pressures are with us all the time and usually to questionable effect. How often is an initial cost saving taken at the expense of the whole life cycle cost? How many procurement executives are incentivized on achieving a low initial cost, rather than a low whole life cost? How often are efforts of engineers to provide a specification promoting low life cycle cost, sacrificed to achieve lowest initial cost targets?

How often does a low initial cost lead to greater cost down stream?

The flight to low cost country sourcing drives the argument that parts can be obtained so economically that extra spares can be purchased if, or in case, something goes wrong.

Responsible low cost country sourcing is to be applauded but requires additional effort to ensure adequate quality and reliability first time.

Reliability is the key to cost control. How many extra train sets have to be provided just in case something goes wrong.

What is the real cost of spares? In addition to the cost of spare train sets, spare parts, depot space, warehousing, maintenance engineers and fitters, and the cost of breakdowns, there is also the Environmental cost.

Sub optimal product may have a lowest first cost, but it consumes more or less the same scarce raw material and energy as the optimal product.

Labour mismanaged or misdirected or misallocated to the production of suboptimal designs consumes scarce raw material and energy in the production of sub standard product.

The consumption of raw material in the production of sub optimal is a contributory driver to the inflation in commodity prices.

Train Availability will necessitate that sub optimal product be replaced sooner and more frequently than optimal product and the replacement process will consume more scarce raw material and energy. Recycling may recover some material, but it will absorb energy in the process. A long life product is much more environmentally friendly than a short life recyclable product.

Sub optimal product requiring more frequent replacement lacks Maintainability.

While sub optimal product may have the lowest first cost and may not compromise Safety, it will certainly not have the lowest whole life Cost, it will not have optimal Reliability, and since it will consume more material and energy it will not be Environmentally friendly, it will not contribute to train Availability and it will have sub optimal Maintainability.

The LPA philosophy is to aim for an optimal design, not compromise on safety, use appropriate materials, meet appropriate standards, produce appropriate product with appropriate reliability and low life cycle cost.

LPA offer a typical design life, subject to an appropriate maintenance and repair regime, of twenty to forty years, within which maintenance and failures are anticipated

LPA use Mean Time Between Failure, MTBF, established by test, experience and by assessment to evaluate product reliability. At the design stage LPA use the assessment procedure specified in MIL Handbook 217 issue F to calculate the Theoretical MTBF, which is very conservative and is normally found to be up to ten times more pessimistic than the actual MTBF achieved in operation.

Typical MTBF values achieved by LPA Equipment are as follows;

Mean Time Between Failure (hours)

Equipment                                                         Theory              Operation

Jumper  (Inter car connector)                               250000               <2.5m

Fluorescent Lamp Driver (Inverter)                        200000               <2.0m

Light Emitting Diode Power Supply                      215000               <2.1m

Light Emitting Diode Down or Spot Light              100000 to 70% output

LPA also aim to extend the life of dependant product. For example a dependant fluorescent tube driven by an LPA Excil FLDU can be expected to last at least 20000 hours, up to three times longer than the manufacturer’s expectation.

An apocryphal story has it that when an extra car was inserted into a fleet of train sets which had LPA Excil lighting, the lighting in the new cars lighting was too bright in comparison with the old cars. On investigation it was discovered that although the lamps in the old cars were supposed to be changed every four years, they were actually being changed on failure. Most had been in service upwards of seven years. When all the old lamps were replaced by new ones the light output in the old cars was the same as that in the new cars.

LPA LED lighting products consume 80% less energy than the halogen or dichroic equivalent and last up to 33 times longer!

LPA Niphan connectors are circular. A circle provides a far more secure sealing opportunity than a square or rectangle, thus preventing dust and moisture ingress. An electrical short to the case work of a circular connector is far less likely than in a rectangular connector. Recognising the weakness in a rectangular connector, the DIN Standard requires rectangular connector casework to be earthed. Thus design weakness leads to additional cost without resolving the weakness.  Rectangular connectors are regularly replaced at seven years, while Niphan circular connectors regularly last for twenty or even thirty years

It is time for all of us in the Rail Industry to SCREAM and demand Reliability which is inherently Safe, Cost effective, Reliable, Environmentally sound, ensures train Availability, reduces Maintenance and does not cost the earth!

Peter Pollock

Chief Executive Officer

LPA Group plc

Sept 2007.