Cleaning, cleanliness, and hygiene are all undeniably central factors in human well-being, impacting both sensory experiences and the mitigation of infection spread. With the ongoing societal shift towards increased digitalization and automation, there is a growing interest in leveraging technology to rationalize and improve cleaning processes. Cleaning management systems utilizing connected sensors have emerged to optimize cleaning schedules in diverse settings such as restaurants, healthcare facilities, offices, shops, warehouses, and public spaces. This literature review report explores the vast landscape of publications addressing the topic of sensors that may provide viable data for decision-making algorithms in cleaning management systems. It also includes a few illustrating examples of commercially available sensors, as well as a list of some cleaning management systems on the market that employ sensors and data. Such systems may for instance exploit consumption data, detect visitor presence, and are often utilizing gas sensors. Gas sensors, being able to measure air quality, are maybe of particular interest for improving cleaning of restrooms. Some may be able to detect pure gases (like carbon dioxide), some react to several gases, and some are able to capture complex odours. Literature indicates that advancements in nano materials will likely lead to stable, energy-efficient gas sensors with increased sensitivity and selectivity. Electronic noses, arrays of gas sensors trained by algorithms, enable detection of complex odours and may enhance the selectivity of gas sensors. However, challenges persist, urging the need for continued improvement in gas sensor technology and smell sensing solutions, especially if to be integrated into Internet of Things (IoT) solutions. The review outlines various principles underlying gas sensors, emphasizing the preference for stable, low-energy technologies in IoT applications. While chemiresistive sensors exhibit promise, historical limitations in their sensitivity and selectivity have led to preferring other principles for certain applications, such as non-dispersive infrared and photoacoustic spectroscopy sensors. The review also describes technologies available for detecting other phenomena, including optical, ultrasound, and radar sensors. It is also underscored the potential in combining multiple sensor technologies to comprehensively assess soiling, tailored to specific environmental contexts. Despite significant progress, literature indicates that much work remains to fully exploit the capabilities of these integrated techniques for timely and efficient cleaning in diverse settings.