Abstract: A telescopically extendable and collapsible ladder assembly includes multiple collapsible ladder sections provided with an air damper at the bottom end of tubular stile members. The air dampers provide retardation of gravity induced velocity of the collapsible ladder sections upon collapse of the ladder sections. Multiple air dampers include a throttle valve securing device, for cooperating with a throttle valve of the air damper when the collapsible ladder section is in the collapsed position, to secure the throttle valve in its throttle position and/or an obturator device. The obturator device includes a first obturator member and a second obturator member where the first obturator member and the second obturator member are configured to, when the collapsible ladder section is in the collapsed position, in combination provide additional throttling.

Abstract: A telescopically extendable and collapsible ladder assembly includes multiple collapsible ladder sections provided with an air damper at the bottom end of tubular stile members. The air dampers provide retardation of gravity induced velocity of the collapsible ladder sections upon collapse of the ladder sections. Multiple air dampers include a throttle valve securing device, for cooperating with a throttle valve of the air damper when the collapsible ladder section is in the collapsed position, to secure the throttle valve in its throttle position and/or an obturator device. The obturator device includes a first obturator member and a second obturator member where the first obturator member and the second obturator member are configured to, when the collapsible ladder section is in the collapsed position, in combination provide additional throttling.