1 Emergency and Disaster Response to Chemical Releases Monitoring Module 4

2 Overview It is important to recognize there is no single general-purpose instrument. Instruments that give complementary information must be used to get different views of the same picture. Choosing the right instrument is only the first step in detecting a hazardous material.

3 Terminal Learning Objective Participant will be able to demonstrate the use and describe the purpose of selected detection equipment for response to chemical releases.

4 Enabling Objectives Describe the purpose and use of detection and monitoring equipment. List detection equipment available to response personnel. Identify limitations that must be considered when interpreting readings using various monitoring devices. Discuss the significance of action levels.

5 Introduction Airborne and liquid contaminants can present a significant threat to human health. Identification and quantification of these contaminants is an essential component of a health and safety program during a response.

6 Introduction Monitoring data is useful for:  Assessing health risks to employees and response workers.  Selecting personal protective equipment.  Delineating areas where protection is needed.  Determining actual or potential effects on the environment.  Selecting actions to mitigate the hazards safely and effectively.  Determining the effectiveness of decontamination activities.

7 Monitoring Equipment Calibration Process of adjusting the instrument read-out to correspond to the actual concentration. Involves checking the instrument with a known concentration of gas or vapor to ensure the instrument gives the proper response.

8 Monitoring Equipment Oxygen indicators  Normal air is 20.8% oxygen  Oxygen deficient at 19.5% or less: Displaced Consumed by combustion or reaction  Increased risk of combustion above 23.5%

9 Monitoring Equipment  Combustible Gas Indicators Measure concentration of flammable vapor or gas in air. Read-out in % of LEL. Read-out is relative to the calibration gas. May not show actual % of LEL. For use only in normal oxygen atmospheres. Not for use in oxygen-enriched atmosphere.

10 100% 80% 60% 40% 20% 0% 50% 100% 0% xylene pentane methane ACTUAL % LEL METER READING % LEL Relative Response CGI Meter

11 Toxic Atmosphere Monitors Identify airborne concentration that could pose a toxic risk to response workers and the public. Evaluate the need for, and type of, personal protective equipment. Set up work zones or areas where contaminants are or are not present.

12 Detector Tubes Consists of a glass tube impregnated with an indicating chemical. A known volume of contaminated air is pulled at a pre- determined rate through the tube by the pump. The contaminant reacts with the indicator chemical in the tube, producing a change in color. Detector tubes are normally chemical-specific.

13 Application of Detection Devices Response personnel should not attempt to use a device that:  Does not have capability to detect the substance of concern.  Cannot measure the material at the concentration of interest.  Will not operate properly under the conditions of use.

14 Application of Detection Devices Use the appropriate instrument. A zero reading is not evidence of absence. Assume multiple hazards. Establish action levels.  % LEL and UEL levels.

15 % LEL Action Level 5% 100% LEL 15% UEL Flammable Range METHANE 0% 5% 0% LEL 10% Action Level 0%

16 Detection of Warfare Agents M9 Chemical detection paper M8 Chemical detection paper M257A1 Agent detector kit

17 M256 Front Diagram

18 M256 Back Diagram

19 Warfare Detector Tubes Mine Safety Appliances (MSA) manufactures colorimetric detector tubes to detect nerve, blister, choking and blood agents.

20 Warfare Detector Tubes The Draeger Civil Defense Simultest Kits are designed to produce immediate and accurate detection of eight chemicals, including nerve, blood, lung, nose, and irritating agents.

21 Other Chemical Agent Monitors Military CAM Civilian APD 2000

22 Summary Chemical detection requires a number of different equipment pieces, ranging from simple papers to hand-held/hand-manipulated electronic devices, wet chemistry systems, and sophisticated laboratory instruments. Chemical agent detection and identification requires the knowledge of signs and symptoms coupled with simple detection equipment in order to identify the unknown agent.