Question: When do curlers use sliding shoes?
About the article "Curling", section "Shoes".

Candidate passages:
Curling shoes are similar to ordinary athletic shoes except that they have dissimilar soles; the "slider shoe" is designed for the off foot (or sliding foot) and the "non-sliding shoe" for the hack foot.
The "slider shoe" is designed to slide and typically has a Teflon sole.
It is worn by the thrower during delivery from the hack and by sweepers or the skip to glide down the ice when sweeping or otherwise traveling down the sheet quickly.
Stainless steel was once common for slider soles, and "red brick" sliders with lateral blocks of PVC on the sole are also available.
Most shoes have a full-sole sliding surface, but some shoes have a sliding surface covering only the outline of the shoe and other enhancements with the full-sole slider.
Some shoes have small disc sliders covering the front and heel portions or only the front portion of the foot, which allow more flexibility in the sliding foot for curlers playing with tuck deliveries.
When a player is not throwing, the player's slider shoe can be temporarily rendered non-slippery by using a slip-on gripper.
Ordinary athletic shoes may be converted to sliders by using a step-on or slip-on Teflon slider or by applying electrical or gaffer tape directly to the sole or over a piece of cardboard.
This arrangement often suits casual or beginning players.
The "non-sliding shoe", or "hack foot shoe," is worn by the thrower on the hack foot during delivery and is designed to grip.
It may have a normal athletic shoe sole or a special layer of rubbery material applied to the sole of a thickness to match the sliding shoe.
The toe of the hack foot shoe may also have a rubberised coating on the top surface or a flap that hangs over the toe to reduce wear on the top of the shoe as it drags on the ice behind the thrower.
In this event, curlers must use a "stick" to throw the rock.
"Sticks" are usually used by disabled and elderly athletes unable to throw the rock by sliding along the ice.
The event began in 2007.
Winners: 2007: Del Hicke 2008: Harold Peltzer 2009: Harold Peltzer 2010: Ed Ferguson 2011: Bruce Jeffrey 2012: Bruce Jeffrey 2013: Carl Glatt 2014: Carl Glatt  
Although the manufacturer says, "While protective gear is not required, we highly recommend its use when the wheels are in the shoes," most users do not wear such gear, largely because these shoes are worn for everyday use (unlike more specialized sporting equipment such as inline skates). 
Only curlers with lower limb mobility problems are allowed to compete.
The expectation is that most curlers will use a wheelchair in their daily life.
Lower leg amputation competitors are allowed to participate in wheelchair sport following classification rules for them based on functional mobility. 
The use of spiked shoes—like in running—is not required to play pesäpallo.
However, they do help the player substantially in rapid situations, especially when playing on modern artificial grass fields which are very slippery to ordinary sport shoes.
The artificial turf differs from what is used in football fields.
There are only a few manufacturers producing spikes designed for pesäpallo and many players use normal running spikes.
Some shoes have also spikes at the heel but mostly spikes are positioned under the ball of the foot.
Usually there are seven spikes in a shoe and they are 3–15 millimeters long.
When playing on artificial turf the maximum length of spikes is 6 millimeters.