BS 12604:2017 pdf download – Industrial, commercial and garage doors and gates – Mechanical aspects – Requirements and test methods
4.3.2 Unintentional movements due to wind
When relevant, the door shall incorporate means suitable to prevent movement of the door due to the influence of wind. These means shall be effective at the relevant terminal position(s).
4.3.3 Uncontrolled movements of vertically operating doors A vertically operating door leaf shall come to a stop and stay in position when released in any position during the opening or closing movement in normal operation.
4.3.4 Safeguarding against dropping of vertically operating door leaves Vertically operating door leaves shall be safeguarded against dropping when in normal use or when a failure of a single element of the suspension or balancing system occurs. The failure of the connection between drum and curtain of a rolling door shall also be taken into consideration if the door when in the fully closed position does not cover at least half of the circumference of the roller.
The door shall not be able to close uncontrolled if a component fails. The design of the door shall also ensure that in case of a single failure the resulting short-term transient loads will not cause secondary mechanical failures of other elements of the door. Elements of the suspension or balancing system which could fail during operation of a door are balancing springs, counterweights, steel wire ropes, pulley, drums, chains, straps, belts and their attaching parts. Rigid parts such as shafts or levers, provided that they are dimensioned and designed for the maximum load and foreseeable overload, need not be considered as a potential cause of the suspension or balancing system failure. Safeguarding against dropping can be achieved by either using an anti-drop safety device or by other design features incorporated into the door. Safeguarding against dropping shall fulfil the following requirements:
a) in the event of a failure in the door suspension or balancing system, the main edge of the door leaf shall not move downwards more than 300 mm even in case of bouncing;
b) after the door leaf has been stopped by the anti-drop safeguarding, it shall be held safely in the same position, as long as no further action in accordance with the user instructions is carried out. User instructions shall clearly specify when a competent person is needed to further operate the stopped door;
c) the anti-drop safeguarding shall be automatically activated in the event of a suspension or balancing system failure;
d) an anti-drop safeguarding shall be designed to take the full dynamic load of the door leaf;
e) further, any component affected by the action of the anti-drop safeguarding shall be designed to bear the resulting dynamic forces;
f) parts of the anti-drop safeguarding or other door components may need to be replaced after activation of the anti-drop safeguarding. Unless activation of the anti-drop safeguarding does not cause any deformation and/or damage which impairs further operation of the door and of the anti- drop safeguarding, instructions for use shall specify parts to be replaced and whether the replacement can be carried out by the user.
The requirements of this paragraph can be disregarded if the following two requirements are simultaneously fulfilled:
— the maximum out-of-balance of the door leaf static force occurring at the primary closing edge of the door does not exceed 200 N when there is a suspension or balancing component failure; and
— the failed component is clearly visible or detectable during normal operation of the door.
4.3.5 Safeguarding against dropping of hinged doors Hinged door leaves shall be safeguarded against dropping when in normal use or when a failure of a single element of the fixing system occurs. The door leaf shall not be able to move uncontrolled if a component fails. In case a hinge or other supporting means breaks or is damaged, the anti-drop safety device shall be able to keep the leaf in position with a maximum displacement of 300 mm from the rotation axis. The door shall also be fitted with a device which avoids that the door leaf, during the opening or closing movement, can be lifted more than 50 % of the length of the pin of the hinges or any other supporting means (“anti-lifting” device).