RIO DE JANEIRO, Apr. 23 -- A Petroleo Brasileiro SA inquiry commission Monday said a gas accumulation might have helped trigger explosions on Mar. 15 that damaged the P-36 platform, which sank later.
The P-36 was a 40-story platform, the largest semisubmersible of its kind, and was insured for $500 million. The blasts killed 10 workers immediately and another worker died later in a hospital.
Carlos Heleno Neto Barbosa, the commission's coordinator, said misalignment of venting ducts might have contributed to the blasts.
A tank for residual gases was located inside the support column where the blasts occurred. That tank may have caused gas to collect there. The blasts happened in the support column, and water later got into other compartments, causing the sinking of P-36.
The commission's preliminary report also said the explosions did not cause the rupture of the hull's steel base or of the support column.
The flooding of the P-36 was caused by the rupture of ducts in the interior of the column, said the commission. The commission will release a final report June 15.