A smoke detector is shown in which blue light is directed through a scattering volume (9) from a radiation emitter (3) and infra-red radiation is also directed through the scattering volume (9) from an infra-red source (3A). Radiation forward-scattered by any particles in the scattering volume (9) is directed by a mirror (13) onto a photodiode (15) which produces an output to control means (16). The emitters (3,3A) are pulsed at different frequencies, enabling the control means (16) to produce s...

An access system for a vehicle includes a gateway module that connects to the vehicle data bus, and an interface system coupled to the gateway module via a gateway bus. The interface system is also coupled to a ramp control subsystem that operates to stow and deploy a ramp for providing wheelchair access to the vehicle. A door control subsystem is coupled to the vehicle data bus and operates in response to data signals sent over the vehicle data bus. The gateway module is configured to relay sig...

A rope and method of making the same. The rope is adapted to engage a structural member and comprises a plurality of yarns. At least one of the yarns comprises a first set of first fibers and a second set of fibers. The first and second sets of fibers are combined using a false twisting process such that the second fibers do not extend the length of the rope and the second fibers indirectly bear tension loads on the rope. The first fibers substantially determine load bearing properties of the ro...

A rope and method of making the same. The rope comprises a plurality of yarns. At least one of the yarns comprises first and second sets of fibers. The first fibers are formed of a first material, and the second set of second fibers at least partly surrounds the first fibers. The second fibers are formed of a second material. The first material defines a set of operating characteristics adapted to bear tension loads on the rope. The second material defines a set of operating characteristics adap...