Emergency services responded to an incident involving a chemical substance at a property in Fletcher Close, Southgate, Crawley, in the early hours of Sunday morning.
Sussex Police said officers and other emergency services were called to the address at around 5.10am on Sunday, 13 September.
A 40-year-old man was taken to hospital for treatment for injuries following the incident.
A 40-year-old woman has been arrested on suspicion of grievous bodily harm (GBH). She was also taken to hospital as a precaution.
Police have stressed that there is no wider risk to the public.
A temporary road closure was put in place in Fletcher Close while emergency services dealt with the incident at the scene.
