Charles was a construction worker employed by an independent contractor to do certain work for D. Charles was placing an aluminum ladder between a scrubbing tower and an open scrubbing pit or vat containing about 95% hot water and 5% acid and chemicals. The space was narrow between the tower and the pit, and Charles suddenly stepped backward causing one of his legs to enter the pit. He could not maintain his balance and he floundered and fell completely into the pit. He was critically burned and his death resulted some four days later. D maintained covered and uncovered concrete pits or vats containing various types of corrosive liquids. D also maintained a scrubber. In conjunction with the scrubber, and located approximately three to four feet from it, D maintained two open concrete pits that were used to hold and circulate scrubber water back into the scrubber. These scrubber pits were completely open and exposed. The scrubber water solution was composed of approximately 95% water as well as certain amounts of corrosive chemicals. The temperature of the scrubber water was very hot. Charles had been working on D's premises for several months. All employees on D's premises had been warned of the dangers of the pits, and it was common knowledge that they contained hot water and harmful chemical liquids. Between the sidewall of the scrubber and the edge of the vats is about three or four feet, and one could narrowly walk between the scrubber and the vats. P, Charles’ wife, sued D. P claimed that despite Charles being an invitee, D had an affirmative duty to protect invitees and others from the extra-hazardous and dangerous conditions on the premises regardless of general knowledge of the dangers. D claimed that it owed an invitee no duty to warn or protect against dangers which were open and obvious. D invoked the defense of volenti non fit injuria. The court granted D’s motion for summary judgment. P appealed.