5 minimum requirements for watertight doors
Fire and blast protective architectural doors can have additional features in order to protect against other sorts of risks. Water tightness is one of such an additional feature. Watertight doors prevent the ingress of water from one area to another during flooding or accidents. The doors are used on onshore or offshore structures where flooding risks are high and on (defense) ships.
According to SOLAS, watertight doors are expected to be kept closed, unless:
- It is agreed that passage of passenger of crew is permitted. The door must be immediately closed when transit through the door is complete or when the task which necessitated it being open is finished;
- Certain watertight door may remain open only if considered absolutely necessary. This will be determined by the SOLAS Administration.
The NORSOK standard outlines detailed minimum requirements for watertight doors.
Requirement 1. Hydraulic operation system
Hydraulically operated watertight doors are strongly recommended to be equipped with a safety device to prevent accidental injuries to personnel.
Requirement 2. Closing and locking
The closing of watertight doors should be fail-safe, which means that when there is a loss of control power the door shall close automatically. The doors should also be equipped with a mechanical locking device in order to prevent the door from opening accidentally in an emergency.
Requirement 3. Fire rating
As a minimum, watertight doors should have the same fire ratings as the compartment of installment.
Requirement 4. Control, alarm and indication
It should not be possible to remotely open doors from the central operating console. Furthermore, there should be warning lights on each side of the door in order to indicate that the door is in “door closed” mode.
Requirement 5. Threshold
The doors a required to have a maximum threshold of 20 mm without recess. There should be no use of hinged plates. To be able to achieve a threshold that is as low and obscuration free as possible, detailing of threshold in material handling routes should be carefully coordinated.
More information about fire and blast rated doors
Want to know more about watertight doors? Download our eBook Fire and blast rated doors for more information!