This is an important research methodological question that I am more than happy to talk through with you at some point. These issues were seriously considered before the survey launch. At the moment though I’m too busy trying to make a difference to spend much time explaining.
The survey is identifying workplaces of bad practice and particular clusters of reported problems - little or no social distancing, face to face contact, hotdesking, inadequate cleaning and sanitisation, heating and ventilation systems that are sub-optimal at best, lift occupancy etc.
200,000 words of volunteered testimony confirm the worst problem areas. They make for grim reading. The evidence is being used in real time to make interventions that make improvements. Equally the survey is seeking to identify good practice especially homeworking that can be used as benchmark for raising the health and safety bar generally.