Quakes can be taken lying down: study

Women are more likely to be injured in earthquakes than men and older women are more at risk than younger women, a new analysis of the 2016 Kaiko¯ura quake has found.

While the full reasons for this skew were not identified, it’s thought that females ‘‘were more likely to move to protect others, including children’’ than males.

As a result, 68 per cent of those injured or killed during the Kaiko¯ura quake were women.

That’s casualties.

Meanwhile, elderly people were more likely to fall, slower to get under cover like furniture and had less ability to protect themselves.

The insights arise from a new analysis of ACC data led by Nick Horspool of GNS Science and the University of Auckland.

The researchers also found that children and adults younger than 30 were least likely to be injured in the Kaiko¯ ura event.

The M7.8 quake started just after midnight and lasted about 2 minutes. It’s suggested that children froze and stayed in their beds.

Beds are ‘‘safe environments’’ provided nothing falls on them.

Injuries were most common in the Kaiko¯ura and Marlborough regions, but there were significant numbers of injuries and ACC claims in the Christchurch and Wellington regions. Claims

420

of

the

620 were also filed in Auckland, Northland and Southland.

This new research is broadly in line with similar research, including from overseas as well as analyses of ACC data from the Canterbury earthquakes of 2010 and 2011.

The majority of injuries (45 per cent) were caused by ‘‘people’s actions’’ – getting out of bed, moving to safety, attempting to evacuate a building, helping children, or taking cover in a door frame.

These actions are generally not consisitent with ‘‘drop, cover and hold’’, the recommnded response to quakes.

Only 8 per cent of injuries were caused by falling contents, and the items most likely to cause injury were furniture (46 per cent), wall hangings (13 per cent) and items on shelves (11 per cent).

Of the two deaths, one was caused by the total collapse of the concrete house which was built in the 1870s.

The other was struck by a wooden pole supporting an internal staircase.

Nine per cent of injuries were caused after the quake, as people evacuated buildings, fled potential tsunamis or cleaned up.

‘‘At low intensities, injuries are dominated by behavioural responses, and as the intensity increases, involuntary causes such as falls or being hit by objects start to cause more injuries’’, wrote Horspool and colleagues from Massey and Otago universities and the Canterbury District Health Board

‘‘This has implications for injury reduction, as it suggests any protective action such as Drop, Cover, Hold, as advised by the New Zealand Ministry of Civil Defence … should be performed … as soon as noticeable shaking begins and before stronger shaking from S-waves occurs in order to minimise risk from falls or being hit by objects.’’

But there is a priviso. About 90 per cent of people injured and the two fatalities were in residential builings – and most were probably in bed.

‘‘The findings from this study indicate that for night-time earthquakes people were less likely to be injured if they stayed in bed compared to getting up and moving,’’ wrote Horspool in an email.

‘‘If people are in bed, then we found that staying where they are and putting a pillow over their head to protect themselves is more effective in reducing the chance of injury than trying to get up out of bed.’’

SUPPLIED People who stayed in bed during the 2016 Kaikoura quake were less likely to be injured, a new analysis has found.