EHS masthead EHS Home LBL Home EHS Home EHS masthead

Chemical Hygiene and Safety Plan
spacer
CHEMICAL HYGIENE
AND SAFETY PLAN
CHSP SITE MAP
HAZARD CONTROLS  arrow image 
CONTROLS FOR HAZARDOUS MATERIALS  arrow image
WORK PRACTICE CONTROLS  arrow image
CHEMICAL STORAGE GUIDELINES
DECOMISSIONING LAB AND SHOP SPACES
SPECIFIC CONTROLS 
AND PROCEDURES  arrow image
EMERGENCY PROCEDURES
AND EQUIPMENT  arrow image
APPENDICES  arrow image
FAQs
QUESTIONS
Search the CHSP:
spacer image
EH&S Home
PUB 3000
LBNL Home
LBNL A-Z Index
LBNL Search
LBNL Phone Book
Privacy & Security Notice
spacer
spacer image spacer image

CONTROL PROCEDURES FOR CHEMICALS WITH EXPLOSIVE PROPERTIES

LBNL staff periodically use chemicals with explosive properties (i.e., explosives)

for activities such as bioremediation studies in which the focus is on the materials’ chemical and physical properties as opposed to their explosive properties.   LBNL does not conduct activities in which an explosion or fragmentation hazard exists.  These include the synthesis, development, processing, blending, pressing, machining, testing and detonation of explosives or assemblies containing explosives.

An explosive is any chemical compound or mechanical mixture that is designed to undergo a very rapid chemical change with the evolution of large volumes of highly heated gases and will deflagrate or detonate when subjected to heat, impact, friction, shock, or other suitable initiation stimuli.  Low explosives (see Figure 1) are materials that deflagrate:  they burn more rapidly than materials undergoing normal combustion processes.  High explosives detonate.  Detonation is a process of combustion in which a shock wave is propagated at supersonic speeds.  High explosives are divided into two classes: primary and secondary explosives.

A primary explosive is extremely sensitive to impact, friction, heat, or electrostatic sources. Lead azide, lead styphnate and mercury fulminate are examples of primary explosives. Primary explosives are often used in detonators or to trigger larger charges of less sensitive secondary explosives.  Primary explosives are prohibited at LBNL.   

Secondary explosives (also known as insensitive high explosives) are relatively insensitive to shock, friction, and heat. They may burn when exposed to heat or flame in small, unconfined quantities but normally require initiation from a primary explosive to detonate.  Dynamite, trinitrotoluene (TNT), Cyclotrimethylenetrinitramine (RDX), Pentaerythritol tetranitrate (PETN), 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX) are common secondary explosives.   

At LBNL most explosives are used in dilute solutions.  For explosives in solution concentrations ≤ 25% w/w, the main hazards are those associated with the solvent and the chemical as opposed to explosive properties of the material.  However, if the solvent evaporates, or if the explosive crystallizes or precipitates, then the primary hazard is associated with the explosive.

Chart of explosives categories

Control Measures

  • The following activities involving explosives are prohibited at LBNL:
    • Use of primary explosives.
    •  Development, testing, processing, blending, pressing and machining of explosives or assemblies containing explosives.
    •  Operations that pose an explosion hazard, a metal fragment hazard or a glass fragment hazard. 
  • Work Leads are responsible for identifying explosives used in the work area.  Review sources such as MSDSs for specific compounds. 
  •  Any quantity of explosives, no matter how small, is hazardous. However, the risk from amounts ≤10 milligrams is significantly less than larger quantities.  Therefore, quantities ≤10 mg require no special precautions other than following the requirements in the CHSP.
  •  Divisions shall do a risk assessment in consultation with an EH&S Division Subject Matter Expert for use of explosives in quantities >10 mg.  A formal work authorization such as an AHD may be required. This is determined by the using Division in accordance with the provisions in PUB-3000, Chapter 6, “Safe Work Authorizations.”
  •  Airborne concentrations shall be maintained at or below applicable occupational exposure limits, for the explosive and its solvent.
  •  Visiting scientists periodically bring solid secondary explosives (typically in gram quantities) to LBNL to study their mechanical properties.  These activities shall be coordinated with the host Division, however the transport, handling, use, security and custody of the material shall be overseen by the visitor’s explosives safety experts and LBNL Security and Emergency Operations.  A written security plan shall be developed by the visitors and approved by the hosting Division and LBNL Security and Emergency Operations.  Secondary explosives in quantities exceeding 10 grams are not permitted at LBNL.

Training and Information

  • Employees who either handle or who may be exposed to chemicals with explosive properties are required to complete Chemical Hygiene and Safety Training, EHS 348 (or 345 for Facilities personnel or 352 for summer students). 
  • All employees in the work area must be trained in the specific hazards and controls of the materials being handled. Area-specific training is a line management responsibility.  EH&S Industrial Hygienists are available to provide assistance.
  • flag image Consult the section entitled: Labels, for labeling requirements for primary and secondary containers. flag image
  • The entrance to the work area should be posted with a Caution Placard depicting hazards and emergency contact information.

Substitution and Chemical Inventory Management

  • Identify and use safer chemical alternatives (e.g., materials without explosive properties) if possible.
  • If a safer chemical can’t be used, then limit what you buy or borrow what you need from a colleague in your group or contact the Chemical Management System Coordinator to assist you in finding a source of the chemical at LBNL.
  • Keep working quantities at or below 10 mg if possible. Don’t stockpile chemicals. 
  • Conduct periodic cleanouts to prevent accumulating unneeded chemicals.
  • Procure and use the minimum amount of material required for the operation, or
  • Enter these materials into the Chemical Management System (CMS).

Ventilation

  • Use a fume hood or other appropriate exhaust ventilation system when handling chemicals with explosive properties in a manner that may produce an airborne hazard (such as fumes, gases, vapors, and mists).  This includes procedures such as transfer operations, preparation of mixtures, blending and sonification.

Work Practices

  • Maintain solution concentrations at or below 25% by weight whenever possible.  At this concentration, the primary hazards are those associated with the solvent and not the explosive.
  • Do not allow the compound to precipitate or crystallize. 
  • Control all ignition sources when handling explosives. This also applies to flammable and combustible solvents the material may be either dissolved or dispersed in.
  • Electrically bond and ground containers when transferring explosives that are either dissolved or dispersed in Class I flammable liquids and other flammable and combustible liquids at temperatures above their flashpoints.
  • Storing and consumption of food is permitted in designated areas only.  See the Section entitled “Work Practice Controls” for additional information.
  • Use a mechanical aid or a pipette bulb for pipetting.
  • Open bottles or carboys slowly and carefully and wear protective equipment to guard hands, face, and body from splashes and vapors/gases.
  • Wipe drips/residues from containers and work surfaces. 
  • Wash hands before leaving the work area and prior to consuming food/beverages.

Personal Protective Equipment (PPE):

Skin and eye contact shall be prevented. The following PPE should be worn when handling these materials.  Additional information may be found in the Personal Protective Equipment Section:

  • PPE shall be selected on the basis of the chemical hazard posed by the explosive compound and its solvent.  PPE and shielding for protection against deflagration and detonation hazards should not be necessary because of the limits imposed on the types and quantities of explosives permitted and the stringent handling, storage and work practices required at LBNL.   
  • At a minimum, safety glasses with side shields, laboratory coats (coveralls are acceptable in shop settings) and closed-toe shoes will be worn when handling these materials. This is to be considered as minimum protection and must be upgraded if necessary.
  • Additional PPE such as chemical goggles, face shields, chemical aprons, disposable coveralls, chemically resistant gloves and respiratory protection must be worn if there is a greater chance of chemical exposure. An EH&S Industrial Hygienist may be contacted for assistance in selecting appropriate gloves and respiratory protection. The use of respiratory protection requires an industrial hygiene hazard evaluation and a medical clearance followed by a fit test and training by the Industrial Hygiene Group.
  • Consult “Eye and Face Protection” in the Personal Protective Equipment Section  for guidance on the selection, uses, and limitations of safety glasses, chemical goggles, and face shields.
  • Since many chemicals are skin-absorbers (i.e. agents that readily pass through the skin) it is important to select gloves that are chemically resistant to the material.  Consult the PPE section.  This contains a list of skin-absorbing agents and provides detailed guidance for selecting chemically resistant gloves.  
  • Gloves must be selected on the basis of their chemical resistance to the material(s) being handled, their suitability for the procedures being conducted, and their resistance to wear as well as temperature extremes. Improper selection may result in glove degradation, permeation of the chemical through the glove and ultimately personal exposure to the chemical.  This is a potentially serious situation.  Consult “Gloves” in the Personal Protective Equipment Section for guidance on the selection, uses, limitations, and disposal of chemically resistant gloves.   An EH&S Industrial Hygienist may also be contacted for assistance in selecting appropriate gloves.

Storage

flag image Consult the section entitled Storage Guidelines for hazardous material storage requirements, recommendations and information on chemical incompatibility.  Since the type and quantity of explosives permitted at LBNL are restricted, the solvent in which the explosive is either dissolved or dispersed shall be the main consideration with regard to storage.  Additional requirements are provided below. end flag image

  • Follow the storage guidelines in Control Procedures for Flammable and Combustible Liquids if the material is either flammable or combustible.
  • Maintain solution concentrations at or below 25% by weight whenever possible.  At this concentration, the primary hazards are those associated with the solvent and not the explosive.
  • If several items of explosives in quantities ≤ 10 milligrams are present in one area, but the total inventory exceeds 10 mg, then separate the items by placing them in individual drip trays or flammable storage cabinets to prevent inadvertent combinations exceeding 10 milligrams total mass.

Emergency Procedures

  • Consult the “Emergency Procedures and Equipment” section for emergency actions regarding chemical spill and personal exposure to chemicals.
  • If the solvent evaporates or if crystals or precipitates are visible, contact an EH&S Industrial Hygienist for guidance.  Avoid disturbing the container.
  • In addition to these requirements, the following applies to flammable and combustible liquid spills:
    • Never use combustible or reactive materials (such as paper towels) to clean up or absorb spills of flammable or combustible liquids.  Keep an adequate number of appropriate spill kits to meet anticipated needs. These are commercially available through VWR Scientific.  Typically, products containing diatomaceous earth are used for absorbing organic solvents.
    • An emergency eyewash and safety shower should be located in all areas where flammable or combustible liquids are used. In the event of skin or eye contact, flush the affected area for at least 15 minutes and report to Health Services for evaluation and treatment.

 

Top
Last updated: 08/31/2010
spacer