Operating Procedures

American Portable Nuclear Gauge Association

This is a stand-alone version from the Training Manual. For the full length training manual click here.

All new gauge handlers, transporters or users must first complete a gauge safety certification class.

The RSO or senior gauge user should spend time familiarizing each worker with each type of gauge in use.

The RSO should also familiarize the worker with all aspects of Gauge Operating Safety and Emergency Procedures.

In addition, only users authorized by the company RSO can operate a gauge.

Of upmost importance is a solid understanding of and commitment to the ALARA (As Low as Reasonably Achievable) Principle. The objective is to reduce occupational and public exposures as far below regulatory limits as possible by means of good work practices. The three components of ALARA are:

a)    Time – Minimize the time spent around a gauge by working quickly and returning the gauge to storage when not in use. The shorter the time spent around a gauge will result in lower exposure dosages.

b)    Distance – Always maintain a safe distance when performing a test (10-15 feet should be sufficient). When in transport, always store the gauge in the rear most part of the vehicle.

c)     Shielding – Let the gauge shielding do its job. Never extend the source rod into open air. Always retract the source rod before recording the results. Always check to make sure the sliding block is fully closed when in the safe position.

Where provided, always wear a personnel monitoring film badge or TLD when handling, transporting or operating a gauge.

a)    Never borrow another person’s badge or TLD.

b)    Do not wear the badge or TLD to the doctor or dentist office or any other location where non-occupational radiation exposures are present.

c)     Do not store the badge or TLD near a gauge.

d)     Immediately notify the RSO is you lose or damage your badge or TLD. The RSO should always have an extra badge or TLD in storage for such an occurrence.

e)     Badges or TLD’s should be worn between the waist or chest area (belt loop or shirt pocket).

Storage and Security

All gauges must be stored in an approved and secure storage area. Proper security would include an area with double locked and limited access. An example of double locked would be a lock on the vicinity that houses gauge storage and an additional lock on the immediate gauge storage locker or closet.

Cased gauges should also incorporate two locks – one on the gauge case and one on the handle of the gauge.

When removing a gauge from security make sure that the gauge and gauge case are intact and undamaged. Make sure the sliding block shielding the bottom of the source rod (above where the hole in the base of the gauge is located) is functional and fully closed. A measurement with a radiation survey meter will verify if the sliding block is ajar.

Always sign the gauge out. Gauge owners and the RSO must always know the location of each gauge at all times. Remember, the person signing out the gauge is personally responsible for its well-being.

Remember to post a “Notice to Employees” poster in a public area and a “Radioactive Materials” sign on the storage door.

If changes or quantities occur in the storage location you will need to reevaluate compliance pertaining to public dose limits and security. Please refer to the “Storage, Security and the General Public” section for more information.

Constant Surveillance

Whether transporting the gauge, or using the gauge at the worksite, always maintain constant surveillance and immediate control of the gauge. Keep unauthorized individuals away from the gauge.

Transporting the Gauge

Be nice to the gauge. You are not an airport baggage handler. Don’t try and see how far you can throw or how hard you can smash the gauge case. Gauge cases cost upwards of $400.00. Dragging a gauge case along the ground by its handle is a sure way to wear a hole in the base of the case. Once there’s a hole the case is no longer considered to be a “Type A” package and you will be in violation of the transport regulations.

Gauges can cost as much as a car. Gauges do break or easily lose their precision and calibration.

Before removing the gauge from the storage area make sure the gauge is affixed with all the proper, and legible, labels and markings, and that you have the proper transport documents and procedures in place. Likewise, make sure the transport blocking, bracing and security features are in place.

Store the gauge away from all passengers and driver, and braced, concealed and under double lock and key.

Always have the bill of lading and emergency response sheet in immediate access to the driver (seat beside you or info packet on the driver side door). At the worksite leave the documents on the driver’s seat.

Always return the gauge to proper transport security when not in use at the jobsite.

At the end of the day always sign the gauge in, making sure it is fully operational and secured.

Operational Procedures at the Worksite

Always use the gauge for the purpose intended and according to the manufacturer’s instructions and recommendations.

Again, be nice to the gauge. Do not use the source rod as a drill rod. A hammer should never touch any part of a gauge.

Gauges are most vulnerable to damage while in use at a worksite. Although you are required to maintain constant surveillance over the gauge, you don’t want to find yourself between the gauge and a heavy construction vehicle. Many gauge operators use a flag staked at the top of a fiberglass whip to make the presence of a gauge readily evident. Fiberglass whips can be purchased at most bike shops.

You should first prepare the testing area before bringing the gauge to the test-site. If performing a soils test use the scraper plate to smooth the area and then insert the drill rod into the scraper plate drill rod guide column (first place the drill rod removal device over the column). Hammer the drill rod to create the hole and lift the drill rod out by grabbing the handles of the removal device.

The Scraper Plate Template Method:

Most important, before you lift the scraper plate, use the tip of the drill rod to etch around the sides of the scraper plate. The dimensions of the scraper plate serve as a template for the base of the gauge. Once etched, place the gauge into this rectangle. The source rod opening at the base of the gauge will be situated right over top the drilled hole. Extend the rod into the hole, push the gauge towards the side of the hole – you’re ready to take a test.

By using this scraper plate template method you will be able to operate the gauge without ever seeing the source rod – no need to extend the source rod to guide it into the hole.

Remember to limit your time and keep a safe distance around the gauge while the gauge completes its test. As you re-approach a gauge you will want to first retract the source back into the safe position, then record the results. This allows the shielding in the gauge to limit your exposure.

Note: If you are taking measurements that require an unshielded source rod to be extended deeper than 3 feet beneath the surface you will need to use piping, tubing or casing material to secure the sides of the hole. This material must extend to 12 inches above the surface. Make sure the hole is free of debris. This will protect the gauge from a cave-in.

Any damage to the gauge should be immediately reported to the RSO and emergency steps should be taken. Refer to your company Emergency Procedures for further instructioin.

Gauge Maintenance

The last place you want to find out that the gauge needs maintenance is the worksite. Regular and routine gauge maintenance, according to manufacturer recommendations, will keep your gauge in good operating condition.

First off, most licensees are forbidden to remove the source rod – that takes a special license.

Only authorized users are allowed to clean a gauge. Make sure you are wearing your badge or TLD. Make sure you have a manufacturer’s gauge manual present. Do not directly touch the source rod with any part of your body.

Cleaning tools and an inspection mirror are a must. Position the inspection mirror on a table or counter. Place the gauge upright on the table between you and the mirror and pull the gauge handle towards you. This will tip the base of the gauge away from you and towards the mirror. Lean your arms and hands over the gauge to remove the base plate, using the mirror image as a guide. This will keep the gauge shielding between you and the bottom of the source rod.

Perform sliding block removal and cleaning per the manufacturer’s recommendations, including debris removal and lubrication. That is also an effective way to check the position of the sliding block mechanism. Asphalt build-up on the bottom of the gauge can usually be removed with a cleaner like WD-40.

Anything beyond routine maintenance must be performed by the manufacturer or an approved and licensed service provider.