From past experience, many public and building safety incidents caused by typhoons could have been avoided if proper precautionary measures have been taken.
Tips on Precautionary Measures
- Inspect roof, podium, flat roof and basement (including car park) to ensure surface water drains and rainwater manholes are in good working order without blockage;
- Inspect all installations at the building exteriors (e.g. scaffolding, signboard, advertisement, decoration) and arrange with the owner/occupant to ensure such are in secure and safe conditions;
- Provide suitable pumping equipment at areas of flooding risk such as electrical and mechanical plant rooms and basement car park;
- Inspect slopes and retaining walls within the development to ascertain any anomalies (e.g. cracks, drains blocked, mud oozing, fallen rocks);
- Provide proper protection materials or devices for windows, glass doors and glass panels in exposed positions;
- Ensure gondola (if any) parked at safe location and is properly secured; and
- Remove/relocate the potential target/object that may be hit by a fallen tree/branch, or restrict access/cordon off the area within the possible tree fall zone.
- Please impress upon your property management company staff to ensure that the suitable precautionary measures are taken.
- After inclement weather, please appoint competent persons to carry out inspections and the necessary repair works as soon as possible.
Buildings Department may regularly issue circular letters reminding building professionals and registerd contractors the safety of scaffolding and tower cranes in construction sites during typhoon season. Please refer to "Related Information" for details.
Safety of Scaffolding
From past experience, most of the incidents involving the collapse of or related to scaffolding could have been avoided if the following site measures had been taken:
- sufficient ties of adequate strength are provided to secure the cantilever portion at the topmost floor;
- the height above the topmost floor should not be over-extended (maximum one floor);
- adequate putlogs, ties, struts, bracing and steel brackets are provided to secure the scaffolding framework;
- plastic sheeting should be removed and the scaffolding above the topmost floor should be lowered to not more than half of the floor height under safe circumstances when a tropical cyclone warning signal or a strong monsoon signal is announced; and
- no loose materials should be placed on/near any scaffolding, or near the periphery of the site.
Please impress upon your site supervision staff on the importance of the safety of scaffolding and ensure that the above site measures are taken in all scaffolding. When the building works have been completed, the related scaffolding should be dismantled as soon as possible. Also, any scaffolding which remains idle should be promptly removed.
Safety of Tower Crane
Suitable safety precautionary measures should be drawn up with regard to the types of crane towers being used, surrounding site conditions and the tower crane manufacturers’ recommendations. In general, the following safety precautionary measures against strong wind may be taken:
- The main jib should be slewed to the side of the tower away from the wind, and then put into free slew. However, care must be taken to ensure that the jib would not collide with adjacent structures or overhead power cables;
- The trolley of the crane with horizontal trolley jib should be placed near to the tower at minimum radius and the hook should be raised to its highest position;
- The jib of luffing jib crane (including the articulated jib crane) should be brought to a position at 15° to the horizontal or other position according to the manufacturer’s recommendation and the hook should be raised to its highest position;
- If the manufacturer recommends to tie the jib and/or the hook to the specified anchorage points above the slewing ring, it should be made sure that the tie wires are of adequate strength and are tightened up properly; and
- If situation warrants, the height of the crane tower above the topmost floor should be lowered as far as practicable.
With consideration of construction conditions, works progress and special constraints, tailor-made precautionary measures should be drawn up for different construction sites and the necessary arrangement should be made as early as possible (in particular when extra costs are involved for implementing those measures). Before the approaching of the typhoons, you should make sure that the precautionary measures in place are properly implemented and timely completed.
Updated Contact Information for Emergency Situations
If there are emergency incidents happened on site during the course of typhoon, staff of this Department may need to contact the authorized person, registered structural engineer and/or registered geotechnical engineer for timely handling those situations. Hence, these registered building professionals are requested to inform this Department as soon as possible if there are any changes of their emergency contact telephone number or fax number, by using the letter attached to PNAP ADM-3.
Follow up Action after Lowering of Typhoon Signals
After lowering of the typhoon signals, the registered contractors should inspect all areas of their construction sites as early as possible, and carry out necessary remedial works immediately if damages are found. Before the resumption of the construction works, it should make sure that the sites are in a safe condition.
- Repairs to Curtain Wall, Glass Wall and Cladding
- Safety of Scaffolding and Tower Cranes in Construction Sites during Typhoon Season
- Flood Prevention Measures at Construction Sites
- Code of Practice for Site Supervision 2009
- Guidelines on the Design and Construction of Bamboo Scaffolds
- Code of Practice for Bamboo Scaffolding Safety
(provied by Labour Department)
- Code of Practice for Safe Use of Tower Cranes
(provied by Labour Department)
- Code of Practice in times of Typhoons and Rainstorm
(provied by Labour Department)