17 common ammonia safety issues refrigeration personnel can control
Proper engineering practices and maintenance is especially important when working with ammonia safety guidelines. 17 common issues are highlighted.
It’s always a good time to check up on facility safety — but now the stakes are even higher when it comes to safety violations.
Employers across the U.S. have been facing higher penalties from the Occupational Safety and Health Administration (OSHA) this year. In January 2021, the federal agency announced it was increasing the maximum penalty for serious and other than serious citations to $13,653 and the maximum for repeat and willful violations to $136,532.
That means conducting a safety audit is especially critical if someone has already received citations at any company facility, since a repeat offense could trigger a costly willful violation.
When it comes to ammonia hazards, proper engineering practices and maintenance are especially important now that industries and ammonia safety are under a national spotlight.
For years, Stellar’s refrigeration teams have focused on mitigating ammonia safety risks while visiting food facilities worldwide. Many of the safety concerns we see stem from issues plant personnel have direct control over — and can correct.
Here are the 17 most common issues Stellar has seen when it comes to ammonia safety hazards in food plants (and how to correct them):
1. Poor housekeeping practices (oily or wet floors, storing items in the machine room)
Slip-and-fall accidents are still the primary cause of lost days from work. The reality is that almost all slip and fall accidents are avoidable and the result of a negligent attitude towards keeping floors clean and dry. Additional accidents occur due to treating your machine room (an already dangerous place) as a storage closet. Heavy boxes topple, operators trip over parts left in the aisles, rags/cardboard can catch on fire, items go missing and access to equipment is greatly hindered, which leads to bad work practices.
Correct it: A clean work area is a safe work area. Ensure floors are clean, free of oil and water and that the ammonia machine room is not being used as a storage room.
2. Blocked escape routes from areas with ammonia present
It may seem obvious when pointed out, but don’t store a big pallet or spare motor (really anything) in front of an emergency exit. We see this mistake in our industry entirely too often, hindering access to the exit or blocking it completely causing it to be unavailable during an emergency situation.
Correct it: Ensure all escape routes and marked aisles are kept clear at all times. Nothing should stand between someone and a safe and fast exit.
3. Poor pipe quality beneath insulation
Insulation traps thermal energy, but also traps moisture intrusion and hides corrosion from sight. Pitting that is obscured from view is allowed to get progressively worse until ammonia can eventually begin leaking.
Correct it: Check for corrosion under insulation (CUI) by conducting spot checks or non-destructive testing (NDT), often performed during your 5-year Mechanical Integrity audit. Prevent pipe corrosion by using a corrosion inhibitor or utilizing stainless steel pipe.
4. Absence of adequate pipe labels and/or no maintenance program for labeling
Correct it: Follow the International Institute of Ammonia Refrigeration (IIAR) ANSI/IIAR 6-2019 guidelines for labeling ammonia piping. Replace any label that has faded, torn, become obscured, is incorrect or is peeling off the piping.
5. Equipment is operated outside design parameters
Materials are generally only rated for a specific temperature range. In the refrigeration industry, users may change a setpoint from -20°F to -25°F to try and improve production or make up for lack of capacity; however, the equipment may only be rated for -20°F. Running pumps or compressors at different conditions than intended can overload their motors.
Correct it: Ensure people operate the pumps and compressors within their designated design parameters and temperature ranges.
6. Failure to implement maintenance cycling program on valves
If valves sit in one position for too long, they will eventually seize in that position, so they won’t be able to turn when needed.
7. Operators with insufficient training in ammonia refrigeration operations and safety awareness
Correct it: Per process safety management (PSM), ensure personnel involved with the operation and maintenance of the ammonia system receive initial training and refresher training at least every three years and/or when equipment is upgraded.
8. Unsafe access to frequently used valves, equipment and switches
Controls and items that require maintenance should ideally be accessible from the ground. When they aren’t, there still needs to be a safe way to access them.
Correct it: Items installed high up should have a catwalk or a clear path accessible via a scissor lift or ladder. For out-of-reach valves, there is the option of using a chain actuator.
9. Leak detection systems that are either nonexistent, inoperable, not calibrated or not tied to ventilation systems
Correct it: Perform annual testing on your leak detection systems to ensure alarms work properly.
10. Uncapped vent/drain valves
Correct it: Ensure all valves open to the atmosphere have a pipe plug or cap installed.
11. Removed/propped spring-return oil drain valves
Because oil draining valves have a spring-return mechanism, personnel must actively hold them open to drain oil from the system low-points. In an instant, the individual can let go and the draining will stop. Some personnel don’t like having to hold the valve open and have either removed the spring-return valve entirely or will prop the valve open during draining. This is extremely dangerous and has led to major ammonia releases and fatalities in the past.
Correct it: Always utilize self-closing, spring-loaded valves for oil draining. Keep them in good working order and never remove them or rig them to stay open after someone lets go.
12. Gas mask systems are not readily accessible
Correct it: Keep gas mask systems close to the ammonia source (but not in the machinery room) and ensure operators know where they are and how to properly wear them.
13. Heavy ice buildup on piping and components; not taking weight into consideration
Some pipes (those below 32°F) will build frost either because they are not insulated or not insulated properly. The ice will continue to thicken, adding considerable weight. Pipe supports and the building are not designed to hold this extra weight and will burst.
Correct it: Insulate piping and components properly to avoid icing.
14. Not executing safety switch testing on a consistent schedule
Correct it: Conduct and document annual safety switch testing.
15. Electrical cabinet doors left open
Few recognize the danger in leaving an electrical cabinet door standing open. Some doors actively hold circuit breakers in place and leaving them open has led to breakers and fuses becoming loose and falling out. This has led to fatal electrical arc explosions.
Correct it: Keep electrical cabinet doors closed at all times to prevent risk of shock or fire.
16. No functioning emergency shower/eyewash basins installed in the machinery room and just outside the machinery room main door
Several critical areas must have an eyewash/shower basin installed. Pending the level of exposure, irreversible ammonia burn damage happens in seconds, and a nearby water basin can drastically change the outcome.
Correct it: Verify shower/eyewash basins are installed, maintained and function to comply with the requirements of ANSI/IIAR 2-2021.
17. No ‘Emergency Shutdown’ signage
When an ammonia emergency is in progress, signage posted in an obvious conspicuous location should provide personnel the phone numbers of critical staff, emergency responders and safety personnel. When responders arrive, this signage lets them know essential details of the system as well as how to shut it down. Unfortunately, we occasionally notice that emergency signage is incomplete or missing entirely in some facilities.
Correct it: Post this signage outside the machine room primary door at the very least and anywhere else personnel can easily see and read it. The signage should comply with the requirements laid out by ANSI/IIAR 2-2021 and include items like quantity of ammonia in the system, field test pressure applied and the names and phone numbers of relevant agencies to be contacted in the event of a reportable incident.