Scientific, research, navigational, surveying, photographic, cinematographic, audiovisual, optical, weighing, measuring, signalling, detecting, testing, inspecting, life-saving and teaching apparatus and instruments; blank digital or analogue recording and storage media; computing devices; computer peripherals; black boxes [data recorders]; leak detectors; leak detection apparatus and instruments; tracer gas leak detection apparatus; electronic tracer gas recovery apparatus and/or systems; leak testing devices; leak testing apparatus; leak testing instruments; electronic leak detector calibration instruments; computer software (recorded programs); computer programs (downloadable software); computer platforms in the form of recorded or downloadable software; computer hardware and software, namely software enabling access to databases; diagnostic and troubleshooting software; applications for mobile devices; data processing apparatus; computer interfaces; spectrometers; mass spectrometers