Inclusion Criteria:  Phase 2, training part 1 & 2  Adult male or female, aged 16 years or over. Written (hard copy or electronic) or verbal informed consent provided. Willing and able to wear or carry clothing (e.g. t-shirt) collected as part of Phase 1 from an individual infected with SARS-CoV-2 or an individual not infected with SARS-CoV-2. Has declared non-symptomatic 7 days (as defined by the latest NHS guidance) prior to participation in the training exercise. Would be willing to have a SARS-CoV-2 test within 24 h of the training exercise if required.  Phase 2, training part 3  Adult male or female, aged 16 years or over. Written (hard copy or electronic) or verbal informed consent provided. Has received a positive result for SARS-CoV-2 from a test conducted within the past 5 days. or is experiencing SARS-CoV-2 symptoms. Willing and able to share, or grant access to, their SARS-CoV-2 test result. Has access to private outdoor space (e.g. front garden, driveway), reachable without leaving the location where the participant is self-isolating. Is asymptomatic or mildly ill (i.e. not requiring hospitalisation, able to walk short distances and stand for up to 15 minutes).  Phase 2 part 4, acceptability and feasibility study  Adult male or female, aged 16 years or over. Written (hard copy or electronic) or verbal informed consent provided. Would be willing to have a SARS-CoV-2 test within 72 hours of the training exercise if required. Willing and able to share, or grant access to their SARS-CoV-2 test result.  Phase 2 part 5, Criteria for all volunteers  Adult male or female, aged 16 years or over Electronic informed consent provided  Additional criteria for volunteers participating in focus groups  Adult male or female, aged 16 years or over. Written (hard copy or electronic) or verbal informed consent provided. Able to access online video-conferencing tools (such as Zoom or Teams).  Phase 3, Deployment testing  Adult male or female, aged 16 years or over. Willing and able to have a SARS-CoV-2 test within 96 h of participation in the deployment exercise. Willing and able to share, or grant access to, their SARS-CoV-2 test result. Verbal or written (hard copy or electronic) informed consent provided by the participant.  Exclusion Criteria:  Phase 2, training part 1 & 2  Younger than 16 years old Informed consent not provided Unwilling or unable to wear or carry clothing from an individual infected or uninfected with SARS-CoV-2. Has not declared non-symptomatic within 7 days prior to the training exercise. Is unwilling or unable to have a SARS-CoV-2 test within 24 hours of the training exercise if required.  Phase 2, training part 3  Adult male or female, aged under 16 years. Informed consent not provided. Has not received a positive result for SARS-CoV-2 or experiencing SARS-CoV-2 symptoms. Unwilling or unable to share, or grant access to their SARS-CoV-2 test result. Has no access to private outdoor space. Participant requires hospitalisation or is unable to walk short distances and stand for up to 15 minutes.  Phase 2 part 4, acceptability and feasibility study  Adult male or female, aged under 16 years. Informed consent not provided. Unwilling or unable to have a SARS-CoV-2 test within 72 hours of the training exercise if required. Unwilling or unable to share, or grant access to their SARS-CoV-2 test result. Phase 2 part 5 Criteria for all volunteers Adult male or female, aged under 16 years. Informed consent not provided Additional criteria for volunteers participating in focus groups. Adult male or female, aged under 16 years · Informed consent not provided. Unable to access online video-conferencing tools (such as Zoom or Teams)  Phase 3 Deployment testing  Adult male or female, aged under 16 years Informed consent not provided. Unwilling or unable to have a SARS-CoV-2 test within 96 hours of participation in the deployment exercise. Unwilling or unable to provide a scent swab. Unwilling or unable to share, or grant access to, their SARS-CoV-2 test result.