Key products

  • Fire detectors

    We are one of the world's leading makers of fire detectors. These are advanced technology electronic products that protect people in large buildings like hospitals, schools, and offices. Each year we sell over 3 million detectors to customers in more than 100 countries. We make smoke and heat detectors based on ionisation, thermistor and infrared sensors.

    Find out more, visit:

  • Gas detectors

    Our gas detectors include portable products to protect the lives of lone workers and also fixed gas sensors which monitor entire industrial sites. Portable detectors can sense flammable and toxic gases and high or low oxygen levels, and the main users are people who work in confined spaces, like tunnels.

    Find out more, visit:

  • Water treatment systems

    We sell non-chemical water treatment systems based on ultraviolet light technology for disinfecting drinking water, waste water, swimming pool water and also industrial water supplies used in food processing and electronics manufacture. Our treatment systems range in capacity from a few litres per hour up to hundreds of cubic metres per hour.

    Find out more, visit:

  • Infrared sensors for elevators and automatic doors

    We are the world's leading producer of opto-electronic sensors that control the safe opening and closing of automatic doors, commonly used at entrances to supermarkets and offices. We also lead the world in sensor technologies that make travel in elevators safe and fast. Our elevator safety products create an invisible light curtain across doors to stop them from closing onto passengers. Our elevator and door sensors use both infrared and microwave technologies.

    Find out more, visit:

  • Ophthalmic instruments

    We make many types of instruments used by optometrists and eye surgeons to examine eyes, test vision and diagnose eye disease. Our principal products are specialist examination lenses, ophthalmoscopes for examination of the internal structure of the eye, and instruments which test the pressure of fluid within the eye.

    Find out more, visit:

  • Water leak locators

    We make the world's most advanced instruments for detecting and locating leaks in underground drinking water pipes. This technology is sold to water companies worldwide. It allows water providers to increase supplies in drought areas and cuts production and distribution costs.

    Find out more, visit:

  • Machine safety systems

    Halma leads the world in machinery safety products called interlocks. These electro-mechanical devices are fitted to hazardous machinery to protect workers from injury or death.

    Find out more, visit:

  • Spectrometers

    We are the world leader in miniature spectrometers. These are optical sensors and analysers which measure the quantity and colour of light to reveal what things are made of and to measure the amount of compounds present in a sample. They are widely used by research scientists and also have practical applications as sensors in products such as atmospheric pollution monitoring systems and cancer diagnosis.

    Find out more, visit: