Under FIDIC Red Book 1999, Sub-Clause 13.8 [Adjustments for Changes in Cost] governs price adjustment based on cost indices. A key provision addresses the situation where the Contractor fails to complete the Works within the Time for Completion.
In such a case, the contract protects the Employer from adverse cost escalation due to Contractor delay. The adjustment of prices is calculated using whichever index is more favourable to the Employer between:
* the index applicable at the time of execution (current index), or
* the index applicable 49 days before the expiry of the Time for Completion.
This mechanism ensures that the Contractor does not benefit from price increases occurring after the contractual completion date if the delay is attributable to the Contractor. It reflects a fundamental FIDIC principle: the Contractor bears the financial consequences of delay for which it is responsible.
Option A is incomplete because it ignores comparison with current indices.
Option B is incorrect because it does not account for Employer protection.
Option D is incorrect because the rule is predefined in the Contract, not subject to agreement.
Thus, Option C correctly reflects FIDIC's balanced risk allocation regarding cost escalation after delay.

Under all FIDIC standard forms (Red, Yellow, and Silver Books, both 1999 and 2017 editions), the Contractor has a clear contractual obligation to notify the Employer (or the Engineer, depending on the form) if it discovers errors, faults, or defects in documents or instructions of a technical nature.
This obligation is explicitly stated in Sub-Clause 1.9 [Errors in the Employer's Requirements] (particularly in Yellow and Silver Books) and similarly reflected in provisions related to documents, drawings, and instructions in the Red Book. The Contractor is required to carefully examine the documents provided and promptly give notice upon identifying any discrepancies, ambiguities, or technical defects.
The purpose of this obligation is to ensure early detection and correction of design or specification issues, thereby minimizing delays, rework, and disputes. It also reflects the principle of cooperation and proactive risk management embedded in FIDIC contracts.
Failure by the Contractor to notify such errors may result in loss of entitlement to additional time or cost if the issue later impacts execution. Therefore, this notification duty is both a technical and contractual safeguard.
Thus, the statement is true, as FIDIC imposes a clear obligation on the Contractor to notify discovered technical errors or defects.

Under the FIDIC Silver Book 1999, Clause 9 governs Tests on Completion, while Clause 12.4 addresses Tests after Completion. These provisions define performance verification before and after Taking-Over.
Option A is correct. Under Sub-Clause 9.4 [Failure to Pass Tests on Completion], if the Works fail the Tests on Completion, the Employer has several options, including accepting the Works subject to a reduction in the Contract Price. This reflects the commercial flexibility within FIDIC, allowing completion despite minor deficiencies, with financial adjustment.
Option D is also correct. Under Sub-Clause 12.4 [Failure to Pass Tests after Completion], if the Works fail post-completion performance tests, the Contractor may be required to pay performance damages. Once these damages are paid, the Works may be deemed to have satisfied the required performance levels. This mechanism ensures that operational deficiencies are compensated financially rather than requiring physical rectification in all cases.
Option B is incorrect because both Tests on Completion and Tests after Completion can coexist within the same contract; they serve different purposes (pre-taking-over vs post-taking-over performance verification).
Option C is incorrect because Tests after Completion are generally carried out by or under the responsibility of the Contractor, not solely the Employer, although the Employer may witness them.
These provisions demonstrate FIDIC's structured approach to quality assurance and risk allocation across different project stages.

Option B is correct: BIM is indeed a digital data technology applicable throughout the project lifecycle.
Option D is correct: Use of BIM requires careful consideration of contract clauses and appropriate adjustments in Particular Conditions.
Option A is incorrect; the 1999 edition does not mandate BIM use.
Option C is false; BIM improves quality, accuracy, delivery times, and cost efficiency.
References:
FIDIC Red Book 1999 & 2017 Editions - BIM and Contract Amendments
FIDIC Contract Manager Study Guide, Module on BIM and Digital Technologies

Under FIDIC Yellow Book 1999, Sub-Clause 8.5 [Delays Caused by Authorities] addresses situations where delays arise due to actions or inactions of public authorities. Sub-paragraph (b) specifically provides that delays caused by authorities may entitle the Contractor to an extension of time, provided certain conditions are satisfied.
A critical condition clearly stated in this clause is that the Contractor must have "diligently followed the procedures laid down by the relevant legally constituted public authorities in the Country." This requirement reflects an important FIDIC contract management principle: entitlement to relief is conditional upon proper Contractor performance. If the Contractor fails to comply with statutory procedures, permit processes, or administrative requirements, then delays cannot be attributed to the authorities for the purpose of claiming time extension.
From a practical perspective, this clause ensures a balanced allocation of risk. While the Employer bears the risk of delays caused by external authorities, the Contractor retains responsibility for proper compliance with all legal and procedural obligations. The Engineer will typically assess whether the Contractor acted diligently before granting any extension of time under Clause 8.4 in conjunction with Sub-Clause 8.5.
Therefore, the statement is correct, as diligence in following authority procedures is a prerequisite for claiming delay under this provision.