8 April 2019
Dear Steve,
OFFICIAL INFORMATION ACT REQUEST
This letter is in response to your enquiry to Lotto New Zealand on 11 March 2019.
Your request was as follows:
I was curious to know the make up of the balls for the lotto draw.
What material are these made of, and is there any risk of increasing
preference of a single ball such as magnetic, warping, out of shape etc. Do
these get damaged in any way during the draw?
Also info such as:
Weight of balls,
hollow or solid
magnetic?
temperature stability
warping probability
material
number of times used
do they get damaged? or robust and replaced as matter of course?
size of sphere, and testing
do they come under some rules and regulations of manufacture
tolerances?
any other interesting info about these.
This is a curiosity thing more than anything as wonder how much effect they
have on the draw (and understand this should be none, and wonder how it is
achieved and monitored)
Please find Lotto NZ’s responses to your questions below:
All of Lotto NZ’s draws are conducted with complete integrity. Independent
scrutineers from Audit New Zealand are present in the studio at all times on the night
of a live draw to oversee all set-up, rehearsals and the live draw to provide
independent assurance of the draw processes and results.
What material are they made of? The balls used for Lotto NZ’s Lotto, Strike and Powerball draws are made of foam
plastic.
Is there any risk of increasing preference of a single ball such as magnetic,
warping, out of shape etc.? No. The balls are not susceptible to any magnetic or static electrical interference.
Under Audit NZ scrutiny, Lotto NZ regularly checks the balls to ensure they fully
conform to size and weight specifications. No more than ten draws are conducted
between these checks taking place. As a result, There is no risk of a single ball being
selected more than any other.
Do these get damaged in any way during the draw? No.
How big are they? Size of sphere? The balls are designed to be 50 mm in diameter, with a margin allowance provided
by the manufacturer that does not affect the randomness of the draws. The
maximum diameter of any ball is 51.5 mm, minimum diameter of any ball is 49.0 mm.
Weight of balls?
Each ball weighs between 11 grams (minimum) and 13 grams (maximum) each.
Within a particular set of balls, the maximum weight variation from the heaviest to
lightest ball is 0.45 grams.
Hollow or solid?
The balls are solid.
Magnetic?
No, there is no metal or magnetic material in the balls.
Temperature stability?
The balls are temperature stable and they do not expand or shrink with variations in
ambient temperatures.
Warping probability?
There is negligible likelihood of the balls becoming misshaped or warped. Each of
the balls are visually inspected prior to each draw, and are regularly inspected to
ensure conformity to specifications.
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Number of times used?
Lotto NZ has four sets of balls – Lotto Set A and B, and Powerball Set A and B. As
part of the draw set-up process, a coin toss takes place to determine which set will
be used for the draw. Audit NZ is present to witness the coin toss.
Lotto NZ uses a practice set of balls for draw rehearsals, with these balls being
replaced with the balls that will be used for the live draw prior to the final dress
rehearsal taking place. As a result, each set of balls is used twice only on each draw
night.
Do they get damaged? Or robust and replaced as matter of course?
The balls do not get damaged during the draws. The balls are visually inspected at
every draw. After a maximum of 10 draws, the balls are individually checked,
cleaned and weighed to confirm they are within the manufacturer’s specifications.
This is done under Audit NZ scrutiny.
To date, no ball has failed these inspections. If a single ball fails at inspection, the
entire set would be immediately withdrawn and a new set would be ordered from the
manufacturer.
Do they come under some rules and regulations of manufacture tolerances?
Yes, the manufacturer supplies the tolerance specifications for size (diameter) and
weight, with prescribed maximum, minimum and variation limits.
Any other interesting info about these? Each set of balls is stored in a secure environment between draws. Following the live
Lotto draw taking place, a tamper-proof seal is applied to the case containing each
set of balls.
The balls are then stored in a chest that features a dual-lock which requires two keys
to unlock – one of these keys is held by Audit NZ, while the other is held by Lotto NZ.
This chest is also stored in a dual-locked steel cabinet, with one key held by Lotto
NZ, and the other by Audit NZ. Once the cabinet and chest is unlocked, Audit NZ
inspects the tamper-proof seal on each set of balls to ensure they have not been
accessed since the previous draw.
Please contact me if you require any further clarification of this information on
(09) 358 9366.
Kind regards,
Kirsten Robinson
Senior Corporate Communications Manager
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