In a secure unit, where the occupant is unattended, an anti ligature waste will be required. These outlets prevent the ability for items to be stashed inside the grate, and any items that do enter the grate area are not able to exit, preventing the ability to use the fixture as a ligature point. This is a priority requirement for these locations, but the disadvantage is that the outlets will have a very poor flow rate. To combat the risk of overflow, the floor of the unit will have an increased fall, often to two outlets, providing the ability for a head of water to form above the grate, increasing flow performance and keeping the water inside the unit's doors. Fixtures in the unit will have a very restricted flow rate, and duration of flow by way of restrictors and timers to ensure that the risk of overwhelming the outlets is reduced. 

As the occupants are unattended, there is the possibility that other fixtures in the unit, such as sprinklers, could be activated to create an event that could cause damage to the rest of the facility or risk to occupants and their security. Often a channel drain with larger capacities will be provided outside the door to manage this extra flow. In the corridor there is less requirement for anti ligature as the occupants will be supervised and therefore the risk is lower.

For areas where occupants are supervised, grating and systems need to be tamper proof. This requires that the components of the system should not be easily removable. This will prevent occupants from using them as weapons, or using the recesses as a place to store contraband. For a perimeter drain or a surface water drain, the Wedgewire grating system is deemed by organisations such as Health NZ to be tamper proof as removal of the fixing screw requires a very specific driver that is not readily available, and it cannot be released by way of using a fashioned tool or knife. Corrections will sometimes require a security screw to be installed in fixtures such as floor wastes, external point drains and sump lids. Allproof can supply these as required across the range of drainage products.

Having a wide range of both anti ligature and anti-tamper solutions allows designers to use Allproof across the range of wastes, from anti ligature, surface water and even in commercial kitchens. Discussing the full package with a local supplier will ensure that the needs of the client (e.g. government departments/ authorities) will be understood, and that their requirements are met. The installer and manufacturer can then work together to supply a compliant and practical solution to secure unit drainage.