On the sixth day of hearings by an independent committee investigating the November 26 blaze in Tai Po that claimed 168 lives, questions also arose about why fire services water tanks on building roofs were being repaired – a move that prompted the entire firefighting system’s shutdown.

The hearing on Tuesday continued to examine the fire alarm system’s deactivation, which the committee’s lead counsel, Victor Dawes, had earlier identified as one of six “human factors” that led to the near-total failure of safety measures at the Wang Fuk Court estate. It had been undergoing extensive renovations when disaster struck.

Lok Sin-ying, a clerk at ISS EastPoint, the estate’s property management company, who was working at Wang Fuk Court, told the committee that she was responsible for filing shutdown notices for the fire hydrant and hose reel system. She said she would also check whether any notices were due to expire.

Acknowledging that she knew the hose reel system had been shut down for months due to water tank repairs, Lok said she did not know that the fire alarms would also be deactivated as a result.

An electrical worker from Victory Fire Engineering, the estate’s fire services equipment contractor, revealed on Monday that the main power switch for the fire booster pump of the hose reel system had been turned off during the water tank maintenance, prompting the deactivation of the linked fire alarm.