The following applies to Arch Hydrazine 15.5%, 35%, 51.2%, 54.4%, 64%, Scav-Ox®, Scav-Ox® II and Scav-Ox® Plus products.
Storage and Handling
Materials of Construction
The selection of proper materials of construction for use with hydrazine is necessary not only to prevent the hydrazine solution from attacking the materials, but also to avoid decomposition of the hydrazine or contamination of the hydrazine solution with impurities. It has also been found that some materials which have proven satisfactory for use with hydrazine at one concentration may become unsuitable at another concentration. Compatibility of materials with several concentrations of hydrazine is shown in Hydrazine Hydrates Products. Due to the complexity of the factors involved, it is only possible to offer general comments about the selection of materials of construction. It is recommended that each application be reviewed and tests conducted to ensure proper selection of materials of construction. Materials generally considered satisfactory for all ranges of concentrations are type 304L and 347 stainless steels with less than 0.5 wt.% molybdenum.
Care must be exercised to prevent explosive conditions either in storage or processing. As previously stated, hydrazine in the vapor state might represent a hazard under certain conditions. To minimize hazardous conditions and maintain integrity of strength, a padding of nitrogen gas should be maintained in all process equipment and storage vessels. Hydrazine solutions should be transferred by a pump made of an appropriate material or by pressurizing with nitrogen at a safely regulated pressure.
Hydrazine can be stored without adverse effects, either to the container or to the product, when proper materials of construction are used. All systems should be cleaned thoroughly before introduction of the hydrazine, and a nitrogen atmosphere should be maintained over the system at all times.
For general storage, the approved container for transporting hydrazine can be used. For extended bulk storage, stainless steel tanks, piping and valves should be employed. Hydrazine should be stored in easily accessible areas, with good natural drainage and prevailing wind. A large water supply should be nearby. Do not store near combustible materials. Storage areas should be isolated from oxidizing materials and operating areas. Storage tanks should be properly diked to contain any major spills.
Persons handling aqueous solutions should wear protective equipment: apron or protective suit, chemical safety goggles and/or face shied, and butyl rubber gloves and boots. Butyl rubber is the material of choice when handling hydrazine. Other compatible materials for protective clothing including: Neoprene, nitrile rubber and Tychem®.
Protective clothing and equipment should be worn whenever the potential exists for contact with hydrazine. This includes:
|• Opening drum plugs or tank truck manway covers
|• Connecting and disconnecting lines
|• Placing pumps into drums
|• Starting and stopping electrical pumps where the switches are near the pumps
|• Breaking hydrazine piping, even if previously decontaminated
|• Flushing out empty drums
Workers should change into clean working clothes each day. If hydrazine is spilled or splashed on articles of clothing, they should be removed immediately and laundered before reuse. Leather shoes should not be worn when handling hydrazine since hydrazine cannot be removed from leather. If hydrazine should be spilled on leather shoes, remove them immediately and discard.
Diluted aqueous solutions of hydrazine are capable of releasing hydrazine vapors to the surrounding atmosphere. Because of the toxicity of hydrazine vapors, care should be taken to ensure adequate local exhaust ventilation whenever hydrazine is handled in open containers.
Ventilation in areas where hydrazine is handled should be adequate to limit the vapor concentration of hydrazine to values below the current Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (PEL) for hydrazine, which is 0.1 part per million as an eight-hour, time-weighted average (TWA) with a skin designation. Detection of a hydrazine odor (similar to that of ammonia) indicates a vapor concentration of 3-5 ppm, which is in excess of the allowable exposure limits. If hydrazine odors are detected, control measures should be taken immediately. When ventilation is not feasible, or when disposing of significant spills, inhalation hazards should be controlled by protecting personnel with a NIOSH/MSHA approved positive-pressure, supplied-air respirator. Follow the OSHA regulations for respirator use (See title 29, Section 190.134, Code of Federal Regulations).
Spill & Leak Procedures
Wear a NIOSH/MSHA approved full-face positive-pressure supplied-air respirator or self-contained breathing apparatus. Follow OSHA regulations for respirator use (see Title 29, Section 1910.134 Code of Federal Regulations). Wear chemical safety goggles, butyl rubber gloves, boots and slicker suit.
Remove all sources of ignition. Isolate area of spill by diking. Stop source of leak. Transfer contents to a non-leaking container or storage vessel. Neutralize spilled hydrazine by diluting with water to a 5% or less solution. Add an equal volume of 5% calcium hypoclorite aqueous solution. Test for neutralization. After neutralization, transfer material to appropriate DOT container for proper disposal. Wash all contaminated clothing before reuse. Discard any contaminated leather articles.