Microsoft Word - SOP - Hands-On Sessions

Rev. 1 - Final

LINE BREAKING FOR 100ml SAMPLE

PART A:

STEP NUMBER

SAFETY AND HEALTH HAZARDS/ STEPS TO AVOID DEVIATION Live line sampling must only be performed by authorized and trained refrigeration technicians.

DESCRIPTION

1

Ensure personal protective equipment is worn at all times and a full-face respirator equipped with NH 3 cartridges is always within reach or worn when pulling the ammonia sample. Determine locations for sampling and choose the most relevant valves. Develop a sampling procedure which may need to be approved by your EH&S manager. that appropriate

2

A representative sample which needs to be tested for water content is the ammonia located on the low side of the system that interacts with the coil or heat exchanger. (Worst place to take a sample is an oil pot this ammonia will not be representative of what is in your coil or heat exchanger) Test the function of eyewash stations for proper operation.

3

Locate nearest safety shower, eye wash stations and emergency exits.

4

Follow your site sampling procedure carefully in order to obtain a representative 100 ml sample of NH 3 from the system. Then verify that all valves have been closed. (see steps 5-14 for basic order of sampling) First connect a sampling stinger or transfer hose to the service valve which will give you the best representative liquid sample. Make sure to inform fellow employees that there will be a pungent ammonia smell in your vicinity temporarily.

Before actual line breaking occurs, cordon off work area from any traffic if necessary.

5

Low-side vessels, associated pumps and piping is the best place to sample. Extra precautions can be taken such as the installation of spring closing valves. If your sampling location is indoors consider putting the ammonia alarm sensors in test mode and inform the proper authorities for your facility. Use an industrial fan or the engine room ventilation so the atmosphere is not stagnant where ammonia can concentrate. Initial liquid flow will flash as it expands, cools the sampling flask and hose or stinger. Once the tube cools then the liquid will start to collect. Note: When using a hose, you will need assistance, or a test tube holder as you operate the service valve and hold the hose or test tube under the stinger. If the ammonia is just left in the flask open to atmosphere it can attract moisture especially in humid climates and give a false reading. Cap the flask with a vented cap and boil off the ammonia. Make sure the vented cap is pointed away from you. Slowly introduce the flask to the water bath, if done too rapidly the ammonia can boil fast enough to blow the vented cap off and or shoot vapor and droplets out the vent.

6

7

Put on the proper PPE then use the stinger or hose to fill the 100 ml evaporation test tube.

8

Once the flask has reached the 100 ml mark, the service valve can be secured and the sample is ready for evaporation.

9

Use a water bath as the heat source for vaporizing the ammonia sample.

Procedure : Testing R717 (Anhydrous Ammonia) for water content Reviewed: 10/26/2023

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