Three abbreviations in a charter party can look like decorative legal text. They are not. SHEX, FHEX, and WWD are the calculator that converts time at port into money - and they decide who owes whom.
Laytime is the time allowed under a charter party for loading or discharging. It is fixed in the contract: "72 hours," "five weather working days," "6,000 metric tons per day." When laytime expires, demurrage starts.
Weather working days count only those days on which weather conditions allow cargo work. A storm, heavy rain, or freezing temperatures that stop operations remove the day from laytime.
The subtlety is evidentiary. "Bad weather" must be proven on the record - port log, met office data, statement of facts. A general impression that it rained will not survive arbitration.
Under SHEX, Sundays and public holidays do not count against laytime. It works in ports that genuinely close on those days.
The definition of "holiday" matters. Local, national, religious? Some charters specify "SHEX local holidays only." Without specification, tribunals default to the official calendar of the port country.
FHEX is the regional counterpart of SHEX for ports where Friday is the rest day - Turkey, Iran, the Gulf states, Saudi Arabia. If the contract covers these regions, FHEX is the appropriate clause.
The two are not interchangeable. SHEX inserted into a charter for discharge at Bandar Abbas guarantees a dispute: the port did not work on Friday, the charterer treats Sunday as a holiday, and the charter says otherwise.
A full day is 24 hours. "Five weather working days SHEX of 24 consecutive hours" means five uninterrupted days, excluding Sundays, holidays, and weather stoppages.
A weather working day generally requires continuous workable conditions across the full working period. Several hours of work followed by a rain stoppage produces only a part day. A full day of stoppage produces zero.
Once on demurrage, always on demurrage.
Once laytime expires, SHEX, FHEX, and weather exceptions stop applying. Demurrage runs around the clock, weekend or holiday, until cargo work is complete.
First, no recorded NOR. Without a valid notice of readiness, the laytime clock has no starting point. In a dispute, the charterer cannot prove when time began running.
Second, no statement of facts. The statement is the day-by-day record: arrival, NOR, work start and stop, weather conditions, holidays. Without it, laytime is an estimate, not a calculation.
Third, unread exceptions. WWD without "of 24 consecutive hours" is read differently from WWD with the qualifier. A single phrase can change the demurrage bill by thousands.
SHEX, FHEX, and WWD turn a charter party from legal text into an operational calculator. Reading them before loading, rather than after the demurrage invoice arrives, is the entire practical lesson.