May I draw your attention to the British Airtours accident in Manchester in 1985.
It was found that major contributing factors to 55 lives being lost were narrow seat pitch and limited access to the emergency exits.
As far as I recall (but I am not too sure about that) extensive evacuation tests carried out afterwards proved that had access to the emergency exits been only a few inches broader this would have speeded up evacuation tremendously because of a well-functioning evacuation flow.
From the official accident report:
The narrow gap of 10Ī inches available between row 9 and 10 seats impeded passengers' access to the right overwing exit. The pressure of passengers on the 10F seat back caused failure of the seat back hinge baulk allowing the backrest to fold forwards creating a further obstacle to egress. Twin bulkheads in the forward cabin restricted evacuation flow to the forward exits after both were open.
...and:
The present regulatory Evacuation Certification Requirements are inadequate in their evaluation of important potential egress restrictions and make no attempt to demonstrate evacuation times in the conditions where speed of evacuation is of prime importance - that of egress in conditions of dense smoke.
...and:
The major cause of the fatalities was rapid incapacitation due to the inhalation of the dense toxic/irritant smoke atmosphere within the cabin, aggravated by evacuation delays caused by a forward right door malfunction and restricted access to the exits.
See
http://www.aaib.dtlr.gov.uk/formal/g...gjl.htm#Safety
There is also a website somewhere about the tests carried out in the wake of that particular accident, but I canīt find it right now. These tests did, indeed, look deeply into the field of passenger flow under evacuation conditions (panic, smoke, etc.)
EDDNHopper