NB! It seems this console command is not compatible with CS2.
Command Profile

SV_DZ_ZONE_DAMAGE

CS:GO

This command sets the amount of damage per second that the "zone" (border) in Danger Zone deals. Default is 1.

Syntax
sv_dz_zone_damage [Damage]

Description

This command sets the amount of damage per second that the "zone" (border) in Danger Zone deals. Default is 1.

Syntax And Arguments

sv_dz_zone_damage [Damage]
Damage The amount of damage per second the zone should deal.