Thank you for reporting on the latest data falsification scandal relating to shock absorbers provided by KYB Corp. to ensure earthquake resistance of buildings. It is always worrying when the government regulator — or a whistleblower — discovers problems with widely installed safety critical equipment. I appreciate that your journalists are providing full transparency. I am sure you agree that the initial reporting is too generic to allay the understandable concerns the public now has.

From experience as a chartered engineer and quality professional, I cannot dispel a suspicion that the underlying root cause may not be "incorrect testing" but A) a design flaw by the manufacturer, B) a materials records traceability issue with sub-suppliers, C) specification omission due to lack of oversight by the builders, D) unclear regulatory requirements or E) something else.

Are the inspection records "missing" or were they "fabricated"? The latter is a crime, the former an omission. Is it possibly a problem of inappropriate sampling regime (e.g. not every damper was tested, or they were not subject to an appropriate endurance test) although actual components might be — but cannot now be 100 percent assured to be — fit for purpose?

The public needs to know more about the estimated extent of the nonconformity, i.e., how far "out of spec" are the installed dampers and what percentage of the dampers are affected? Likely there is a distribution: some dampers are way out of spec, others only marginally, some are OK.

We need to know whether performance degrades over time, i.e., dampers work satisfactorily for an initial period but become unsatisfactory after certain time (e.g. due to oil leakage).

We also need to know what this means for actual building performance in an earthquake.

Finally, how certain can the public be that no other manufacturers have had similar problems? Have they all been checked, or are we assuming they did it right?

THOMAS SCHNEIDER

SHIBUYA WARD, TOKYO

The opinions expressed in this letter to the editor are the writer's own and do not necessarily reflect the policies of The Japan Times.