1.      Process

Use of nitrous oxide as an anesthetic agent in medical, dental, and veterinary environments.

2.      Physical hazards

q       Colorless gas with a slightly sweet odor (inhalation anesthetic).

q       Shipped as a liquefied compressed gas.

q       Nonflammable gas, but supports combustion at elevated temperatures.

q       Incompatibilities and Reactivities: aluminum, boron, hydrazine, lithium hydride, phosphine and sodium.

3.      Health Hazards

q       Symptoms of exposure to nitrous oxide include:

·          Dyspnea (breathing difficulty)

·          Drowsiness

·          Headache

·          Asphyxia

·          Reproductive effects

q       Exposure to the liquid form of nitrous oxide causes frostbite

4.      Personal Protective Equipment

q       EYE PROTECTION

·         Safety glasses, goggles or face shields shall be worn during operations in which nitrous oxide might contact the eyes (e.g., through vapors or splashes of solution). 

·         Ordinary (street) prescription glasses do not provide adequate protection.  Adequate safety glasses must meet the requirements of the Practice for Occupational Education Eye and Face Protection (ANSI Z87.1-1989) and must be equipped with side shields. 

·         Fisherbrand® Chemical Splash Goggles, catalog # 19-041-739 are recommended.

·          Contact lenses should not be worn if the potential exists for nitrous oxide exposure.

q       HAND PROTECTION

·         Use of Nitrile gloves are recommended for use against permeation by nitrous oxide which are available through Lab Safety Supply catalogue # 2BD-14655.

q       LAB COATS, ETC.

·         Lab coats, close toed shoes and long sleeved clothing shall be worn when handling nitrous oxide. Protective clothing shall be worn to prevent any possibility of skin contact with nitrous oxide.

q       SAFETY SHOWER/EYEWASH

·         Where the eyes or body of any person may be exposed to nitrous oxide, suitable facilities for quick drench or flushing of the eyes and body shall be provided within the work area for immediate emergency use. 

·         Bottle type eyewash stations are not acceptable.

5.      Designated Area for Use and Containment Devices

q       Nitrous oxide must only be used in operations that have the requirements listed in Section 6.

q       Laboratory or other use area shall be marked as follows:

Caution

Nitrous Oxide in Use

Potential Reproductive Toxin

6.      Special Handling Procedures and Storage Requirements

q       EXPOSURE MONITORING

q       Users of these materials are required to notify EH&S at 777-3099 of the location of areas where they will be using these agents so that a hazard assessment and air sampling may be performed. 

q       Properly secure store cylinders. (hyperlink to web)

q       Monitor anesthetic equipment when installed and every 3 months thereafter:

·          Leak test equipment

·          Monitor air in the worker's personal breathing zone

·          Monitor the environment (room air)

q       All nitrous oxide work shall be done in the laboratory fume hood. The fume hood’s sash must be in the position where a face velocity of 100 feet per minute is achieved. 

q       Prevent leakage from the anesthetic delivery system through proper maintenance and inspection of equipment. Eliminate or replace the following:

·          Loose-fitting connections.

·          Loosely assembled or deformed slip joints and threaded connections.

·          Defective or worn seals, gaskets, breathing bags, and hoses.

q       Control waste nitrous oxide with a well-designed scavenging system that includes the following:

·          Securely fitting masks.

·          Sufficient flow rates (i.e., 45 liters per minute) for the exhaust system.

·          Properly vented vacuum pumps.

q       Make sure that the room ventilation effectively removes waste Nitrous Oxide. If concentrations of nitrous oxide are above 25 ppm, take the following steps:

·          Increase the airflow into the room.

·          Use supplemental local ventilation to capture nitrous oxide at the source.

7.      Waste Disposal

Return empty cylinders of nitrous oxide to vendor of purchase.

8.      Decontamination of Equipment and Area

No special requirements are needed.

9.      Spill and Accident Procedures

q       In the event of a liquid spill greater than 300 cc, immediately vacate and secure the area.  Contact WFUBMC Security at 716-9111.

q       Provide additional ventilation to the affected area.

10. Training

q       Documented training must be available that a training program that describes nitrous oxide hazards and defines prevention measures exists including:

·          Standard operating procedures for all tasks that may expose workers to nitrous oxide.

·          Proper work practices, controls, equipment, and personal protective equipment that should be used when working with nitrous oxide.