Health Surveillance Techniques should be: 

• Sensitive 
• Specific 
• Easy to perform and interpret
• Safe 
• Non-invasive
• Acceptable 

Examples of Health Surveillance

• Biological monitoring 
  e.g. 2.5-hexane di one (a metabolite of n-hexane) in urine COHb in workers exposed to methylene chloride. 
• Biological effect monitoring 
  e.g. Cholinesterase in blood of workers exposed to certain organophosphorus pesticides 
• Enquiries, inspection or exam by a suitably qualified person 
  e.g. an occupational health nurse administering a questionnaire for symptoms of asthma or rhinitis; or examining the hands for dermatitis 
• Medical surveillance 
  e.g. lung function measurement in workers exposed to substances known to cause occupational asthma; Chest X-rays in workers exposed to respirable quartz 
• Monitoring of sick absence -Review by Occupational Health for work-related trends in sick absence