In its role as the national standards laboratory for the UK, the National Physical Laboratory (NPL) maintains, develops and disseminates, amongst others, the UK's detector spectral responsivity scale and material spectrometric scales (regular, hemispherical and angular reflectance and transmittance). In order to carry this work out detectors, materials, methods and facilities are continually under development at NPL. This paper will present the latest measurement techniques used at NPL that are applicable for the characterisation of infrared detectors and materials. NPL has extensive calibration capabilities, making use of grating and FT spectrometers and tuneable lasers, covering a wide spectral range, catering for single element, array, sub-pixel resolution and photon counting devices. As well spectral responsivity, detector spatial uniformity and linearity measurements are available. The UK spectrometric scales are maintained from 200 nm to 56 μm and include regular, hemispherical and angular reflectance and transmittance scales, and artefacts for the wavenumber and ordinate calibration of mid-infrared spectrometers.