PID Case Study

Case Study

Fuel barge explosion and cleanup
On February 21, 2003, a fuel barge loaded with gasoline exploded at a fuel loading dock on Staten Island, New York
Two workers were killed and another critically burned
The explosion was the result of an accident, not terrorism or sabotage
The barge had unloaded about half its cargo of 4 million gallons of unleaded gasoline when the explosion occurred

As the blaze was at its height, officials used tugs to push a nearby barge loaded with 8 million gallons of gasoline to the other side of the waterway, where they covered it with water and foam to ensure that it did not explode.

USCG photo by PA3 Mike Hvozda

Once the fire was extinguished and the barges cooled, Marine Chemist and Coast Guard personnel conducted structural inspections
Exposure to toxic VOCs was a primary concern
Chemicals of concern included the remaining gasoline, benzene, total BTEX (benzene, toluene, ethylbenzene, and xylenes) and total polycyclic aromatic hydrocarbons (such as naphthalene)

Actual toxicity testing results from gasoline fuel barge #1

Previous Loadings: Cat Feedstock/Crude Oil/Cat Feedstock

SPACE	% LEL	PPM TVOC (iso)	PPM Benzene	%TVOC from benzene
No (1) Port Cargo Tank	0	32.8	0.8	2.44%
No (2) Port Cargo Tank	0	38.2	0.4	1.05%
No (3) Port Cargo Tank	0	45.5	0.4	0.88%
No (4) Port Cargo Tank	0	75.8	0.3	0.4%
No (5) Port Cargo Tank	0	64.3	0.3	0.47%
No (1) Stbd Cargo Tank	0	34.8	0.6	1.72%
No (2) Stbd Cargo Tank	0	44.6	0.3	0.67%
No (3) Stbd Cargo Tank	0	39.6	0.2	0.51%
No (4) Stbd Cargo Tank	0	58.4	0.4	0.68%
No (5) Stbd Cargo Tank	0	64.8	0.5	0.77%

TVOC alarm setting based on fractional concentration benzene for Barge #1

Worst case (No 1 Port Cargo Tank)

TVOC hazardous condition threshold alarm of 172 ppm isobutylene would prevent exceeding the PEL for benzene of 1.0 PPM

41 x .0244 = 1.0004 ppm

TVOC Hazardous Condition Threshold Alarm for compliance with:

Benzene Exposure Limit	1.0 PPM	0.5 PPM	0.1 PPM
TVOC alarm setting	41 PPM	20.5 PPM	4.1 PPM

Actual toxicity testing results from gasoline fuel barge #2

Previous Loadings: Natural Gasoline (3X)

SPACE	% LEL	PPM TVOC (iso)	PPM Benzene	%TVOC from benzene
No (1) Port Cargo Tank	0	37.3	0.0	0%
No (2) Port Cargo Tank	0	44.1	0.1	0.23%
No (3) Port Cargo Tank	0	53.8	0.2	0.37%
No (4) Port Cargo Tank	0	48.2	0.1	0.21%
No (5) Port Cargo Tank	0	68.5	0.4	0.58%
No (1) Stbd Cargo Tank	0	13.2	0.0	0%
No (2) Stbd Cargo Tank	0	29.0	0.0	0%
No (3) Stbd Cargo Tank	0	58.1	0.1	0.17%
No (4) Stbd Cargo Tank	0	48.7	0.2	0.41%
No (5) Stbd Cargo Tank	0	63.3	0.3	0.44%

TVOC alarm setting based on fractional concentration benzene for Barge #2

Worst case (No 5 Port Cargo Tank)

TVOC hazardous condition threshold alarm of 172 ppm isobutylene would prevent exceeding the PEL for benzene of 1.0 PPM

172 x .0058 = 0.9976 ppm

TVOC Hazardous Condition Threshold Alarm for compliance with:

Benzene Exposure Limit	1.0 PPM	0.5 PPM	0.1 PPM
TVOC alarm setting	172 PPM	86 PPM	17.2 PPM