In addition, although cost is of importance, an economic evaluation 

 of materials was not included for two reasons: first, the cost of most 

 synthetic material is variable, and second, total boom cost is heavily 

 dependent on individual boom design and fabrication techniques as well 

 as material costs. Therefore, a material must not be accepted or rejected 

 based on purchase price alone, without considering total procurement 

 costs for a particular boom design and expected useful life. This study 

 was not based on a particular boom design; therefore, the scope has been 

 limited to the technical suitability of the materials. 



MATERIAL REQUIREMENTS 

 General Description of Booms 



Oil spill booms come in a variety of designs, shapes, and sizes; 

 typical is the floating boom shown in Figure 1 . It consists of three 

 basic components: a vertical fence, a flotation member, and a longitudinal 

 strength member. 



The vertical fence, which extends both above and below the water line, 

 may be made of either a rigid or flexible material and usually incorpora- 

 tes ballast along the bottom to keep it properly oriented. 



The flotation member may be an integral part of the fence or attached 

 externally as shown in Figure 1. If integral, the buoyancy may be 

 provided by gas- filled chambers or by plastic foam beads or logs. If 

 external, logs or blocks of rigid or semirigid plastic foam are generally 

 used. 



The longitudinal strength member may be a cable, rope, or chain 

 running the length of the boom or may be a webbing incorporated in the 

 fence fabric. In some boom configurations the load-carrying capacity is 

 developed by the fence material itself. 



Requirements 



The wide variation in boom configurations makes it difficult to 

 identify one material as ''best''; a good material for one boom design 

 may not be suitable for another. However, this study is not concerned 

 with boom design per se; every attempt has been made, therefore, to 

 reduce the impact of boom design on the selection of boom material. The 

 material requirements that follow are based on boom performance character- 

 istics and have been established by consulting current specifications 

 for booms [2] and through consultation with personnel engaged in the 

 design, manufacture, and procurement of booms as well as with those 

 having direct operational experience. The requirements include structural, 

 physical, and chemical resistive properties of the materials. Where 

 possible, applicable standard test procedures have been identified. 



