Instrumentation & Control Technician (Red Seal)

Performs common occupational skills

What should a technician do with a pair of safety glasses found to have a deep scratch across the lens during the pre-use inspection?

1. Buff the scratch out with cerium polish
2. Downgrade them to a chemical splash spare
3. Remove them from service and replace them
4. Log the defect and finish the shift first

A deep scratch weakens the lens and blocks clear sight of the work, so the protective rating can no longer be trusted; the glasses are removed from service and replaced. Using them for short tasks still exposes the eyes, polishing cannot restore impact strength, and passing damaged eyewear to a visitor simply moves the hazard. Pre-use inspection exists to pull damaged protective equipment before it fails.

RSOS 2020 | A-1.02 Uses personal protective equipment (PPE) and safety equipment

Installs and services process measuring and indicating devices

A pressure transmitter is being mounted to measure the level in a tank holding a slurry that can settle in the sensing line. What mounting choice reduces plugging?

1. Mount the transmitter well above the process tap and run a long horizontal sensing line back to it
2. Use the smallest possible sensing-line bore so the slurry velocity stays high enough to self-scour
3. Mount the transmitter close to the tap and slope the sensing line for drainage
4. Leave out the isolation valve so the slurry sensing path is kept as short and direct as possible

Mounting close to the process tap with the sensing line sloped so solids drain back keeps a slurry from settling and blocking the line. Routing the transmitter above the tap with a long horizontal run creates low spots that trap solids, a very small bore plugs faster, and removing the isolation valve takes away the means to clear or service the line. Short, sloped, drainable runs are what keep slurry taps open.

RSOS 2020 | B-5.01 Installs pressure, temperature, level and flow devices

Installs and services safety and security systems and devices

A safety instrumented function is rated at the second integrity level. What range of probability of failure on demand does that level require?

1. A weak band greater than or equal to 10^-1 up to less than 1 for the lowest rating
2. A demanding band greater than or equal to 10^-4 to less than 10^-3 for a higher level
3. Greater than or equal to 10^-3 to less than 10^-2 (1 in 100 to 1 in 1,000)
4. An extremely small probability below 10^-4, the most demanding band

The second integrity level requires a probability of failure on demand greater than or equal to 10^-3 to less than 10^-2 (1 in 100 to 1 in 1,000). The first level allows a higher failure probability, the third level demands a far lower one, and a probability below one in ten thousand belongs to a still higher level. Matching the function's rating to the correct probability band is what proves the safety loop meets its target.

RSOS 2020 | C-13.01 Installs SIS