Abstract: A semi-volatile particulate matter detection device is disclosed for detecting semi-volatile particulate matter in a gas flow. The device has a first filter stage for receiving the gas flow, the first filter stage being configured to capture particulate matter and to be heated to a temperature of at least 150° C. to volatilise semi-volatile particulate matter to produce semi-volatile vapour for passing through the first filter stage with the gas flow. The device also has a conveyance section downstream of the first filter stage to convey the gas flow and the semi-volatile vapour. A second filter stage is configured to receive the flow from the conveyance section. The temperature of the conveyance section and/or of the second filter stage is controllable so as to cause condensation of at least some of the semi-volatile vapour and collect it on the second filter stage. A detector is provided for detecting at least one characteristic of the condensed semi-volatile vapour on the second filter stage.

Abstract: A mattress for a bedding unit. The mattress comprises a body having a first support surface and a second support surface. Each of the first support surface and the second support surface is configured to support a user thereon and each of the first and second support surfaces have a different level of firmness. At least one top portion is removably attachable to either of the first or second support surfaces of the body. The at least one top portion has a level of firmness less than the level of firmness of the first and second support surfaces such that when the top portion is attachable to either of the first or second support surface, the level of firmness of the first or second support surface is reduced. An overall level of firmness of the mattress can be altered by the user selecting either the first or second support surface alone or in combination with the at least one top portion to provide the overall level of firmness of the mattress that is acceptable to the user.

Abstract: There is disclosed a mattress comprising a first border member configured to define an upper periphery of the mattress and a second border member configured to define a lower periphery of the mattress. At least two spring assemblies are positioned within the first and second border members so as to extend between the first and second border members. Each spring assembly comprises an array of coil springs and each spring assembly is positioned such that the coil springs of one spring assembly are not directly connected with coil springs of any other spring assembly.

Abstract: There is disclosed a mattress comprising a first border member configured to define an upper periphery of the mattress and a second border member configured to define a lower periphery of the mattress. At least two spring assemblies are positioned within the first and second border members so as to extend between the first and second border members. Each spring assembly comprises an array of coil springs and each spring assembly is positioned such that the coil springs of one spring assembly are not directly connected with coil springs of any other spring assembly.