Under FIDIC terminology, an ad-hoc Dispute Board is known as a DAB (Dispute Adjudication Board), which is appointed for specific disputes as they arise, rather than standing continuously.

The DAAB is a standing board appointed for the project duration, providing continuous dispute avoidance and adjudication.

Option D refers to arbitration, which is a different dispute resolution method.

Option C is correct: The Contractor is obligated to rectify any non-compliance with prevailing standards promptly.

Option D is correct: The Contractor carries responsibility for design fitness and correctness, even if the Engineer has approved or not objected to the design.

Option A is incorrect; Engineer approval does not absolve the Contractor from responsibility for defective design or works.

Option B is not necessarily required; only non-compliant parts need correction, not entire varied works.

A legally binding contract is typically formed when there is an offer, acceptance, and intention to create legal relations. Under FIDIC contracts:

Option B (signing the Contract Agreement) unequivocally forms a binding contract.

Option D (Letter of Acceptance issued after receiving the Contractor’s Letter of Tender) generally forms a binding contract unless otherwise specified, as the Letter of Acceptance is the formal acceptance of the tender.

Option A (Letter of Intent) is not necessarily a binding contract; it often serves as an interim arrangement signaling intent but may lack definitive terms to form a contract.

Option C (conditional Letter of Acceptance) may not form a binding contract unless the conditions are fulfilled.

Comprehensive and Detailed Explanation:

Options A and B are correct: Both the Red and Yellow Books require the Engineer to certify payments before the Employer pays the Contractor.

Option C (Silver Book) typically places the risk on the Contractor and often provides for payment without Engineer certification, reflecting the turnkey nature of the contract.

Under FIDIC Red Book 1999, retention is calculated as a percentage (stated in Appendix to Tender) of the value of Works executed and Plant and Materials in accordance with Sub-Clause 14.5 that are on or off Site but intended for incorporation.

Option A is correct: Retention applies to the value of executed works.

Option D is correct: It also applies to Plant and Materials under Sub-Clause 14.5.

Option B is incorrect; advance payments and repayments are not part of retention calculations.

Option C is incorrect; changes due to legislation or costs are not included in retention calculation.

Y is not correct. The Contractor’s obligation to commence works depends on the Commencement Date notification as per the contract. If the Employer requests commencement on the 14th day after signing, and the contract allows or the Engineer has not yet notified otherwise, the Contractor should comply unless formally instructed otherwise.

Delaying work beyond the contractual or Employer’s instruction without valid cause may be considered breach of contract and could lead to claims against the Contractor.