zone 1 testing: do you dare? - safetychain software downloads... · 2018. 10. 24. · checkwe...

ZONE 1 TESTING: DO YOU DARE?

Copyright © 2018 SafetyChain Software

Zone 1 Testing: Do You Dare?

It is a widely held belief throughout the food industry that zone 1 surfaces, or those with which

products come into direct contact, should never be tested for pathogens. This is due to the high recall

risk companies face if such surfaces are found to be contaminated. However, when determining the

appropriate environmental monitoring approach to take, many companies find themselves asking: Is it

really wise to ignore our greatest food safety risks?

While choosing to test zone 1 for indicators alone, pathogens, alone, or both combined is ultimately a

decision left in the hands of each individual company, those taking the most aggressive approach are

likely to fare best in terms of risk mitigation. In the following guide, we’ll present some considerations for

performing zone 1 testing, including:

check Recent food industry issues and events involving high-risk pathogens

check Key insights into indicators vs. pathogens, zones, and out-of-spec results

check Top reasons companies do or do not perform zone 1 testing

check What your facility can do to minimize risks of pathogens

check Relevant pathogen case studies to consider

check Steps for establishing a response plan for out-of-spec results

We’ll begin by examining some recent events in the food industry which have prompted professionals to

take a closer look at their environmental monitoring programs.



Recent Pathogen-Related Issues The food industry has seen a number of major recall events in recent years. Most notably, salmonella has

been found in peanut butter and hydrolyzed vegetable protein (HVP), while listeria was present in ready-

to-eat (RTE) meats. Both pathogens were found in cantaloupe, leading to widespread recalls and dozens

of consumers falling ill.

Oftentimes, serious food contaminations such as the instances listed above result from failure to have

a strong environmental monitoring program (EMP). A robust and effective EMP verifies the preventive

controls used in your facility to control pathogens are indeed working, and its main purpose is to find

pathogens or allergens in the environment before they contaminate product. Your EMP also allows you

to assess the effectiveness of your cleaning, sanitation, and employee hygiene practices.

Where Should You Test?

Using a zone approach is recommended, but it is up to each food manufacturing or processing company

to apply the level of complexity that suits them. Some facilities take a two-zone approach, separating

areas into direct product contact surfaces and non-product contact surfaces. Others use three or more

zones.

Regardless of which areas you test, your facility should have a detailed environmental monitoring

program.



The Key Attributes of an Environmental Monitoring Program

Every EMP should encompass the following attributes:

check Standard operating procedures (SOPs) for cleaning, sanitizing, and identifying potential

pathogen and allergen harborage sites, as well as identifiable reasons behind the sanitation

program

check Environmental testing methods to collect data points and assess the effectiveness of your

preventive controls

check Evaluation of results and root cause analysis when positive environmental samples are found

check Corrective actions taken based on root cause analysis

Which Pathogens Should You Look For?

While historical data may guide the direction your EMP takes, it’s important to note that all pathogens

could potentially be found in any food, ingredient, or environment at any time. With that said, this guide

will focus primarily on the two pathogens which have had the most significant impact on the food

industry in recent years: salmonella and listeria monocytogenes. Nonetheless, many of the practices and

principles described herein can effectively be applied to pathogens and allergens of any variety.

Salmonella is the target organism for environmental monitoring of product-contact and non-product

contact surfaces in a low-moisture food manufacturing facility. Listeria monocytogenes is the target

organism for environmental monitoring of product-contact and non-product contact surfaces in a high-

moisture food manufacturing facility. Additionally, unwanted allergens should be looked for on direct-

product contact surfaces throughout your facility, if needed.

In the coming section, we’ll explore some key information on zones, indicators, pathogens, and more.



Key Insights for Zone 1 TestingIndicators vs. Pathogens

When setting objectives for your EMP, the question of what to test for must be answered. Oftentimes,

food industry professionals find themselves asking: Which is better, indicators or pathogens? Keep in

mind that an indicator is an analyte, species, or group of microorganisms or analysis whose presence or

level may indicate the potential presence of a pathogenic organism or allergen to the extent to which

a GMP or hygiene practice was followed. In other words, testing for indicators allows you to establish

data points that determine whether your GMPs are working effectively for controlling food safety on the

chosen surfaces. While some facilities test for indicators, others take the more thorough route and test

specifically for pathogens themselves. We’ll review considerations for both approaches in greater detail

in an upcoming section.

What Constitutes Out-of-Spec Results?

Out-of-spec results occur when one or more of the following events take place:

check A visual inspection fails; i.e., the surface is noticeably soiled

check An indicator (ATP, APC, Coliform, Ebac, protein, etc.) exceeds the action limit

check A pathogen is detected

check An allergen is detected



A Detailed Guide to Zones

We reviewed zones briefly in the previous section, but in order to formulate a detailed EMP, it may be

helpful to take a closer look at how most facilities define various zones.

check Zone 1: The area in the plant where there are direct product contact surfaces immediately after a

microbial reduction step and before packaging

check Zone 2: This zone comprises non-product contact areas that are adjacent to product contact

surfaces

check Zone 3: Non-product contact areas within the processing area that are removed or far away from

product contact surfaces but could result in cross-contamination

check Zone 4: The farthest from the production area, this zone includes all non-product contact

surfaces outside the processing room

When is Environmental Monitoring Necessary?

If you have completed a thorough hazard analysis in your facility, you should be able to determine the

risk of environmental contamination of your products. For your reference, the following criteria can also

be utilized to determine the risk of a process. Naturally, higher-risk processes are recommended to have

environmental monitoring programs.

check For RTE foods: Will a lethal microbial treatment be applied to the product prior to consumption?

For instance, in the raw meat industry, it is assumed that the final customer will apply an

appropriate kill step to address potential pathogens. It is essential to consider the intended use of

each product to fully understand the risk of contaminants and their potential hazards.

check Post-process contamination: Is the process fully enclosed? Where is the product exposed?

Consider any potential opportunities for cross-contamination.

check Has the process, or a similar process, been documented to have had environmental

contamination?

check Verification: Is there a routine wet, chemical sanitation procedure that requires verification of

effectiveness?

Now that we’ve covered some background information on zones and environmental monitoring, let’s find

out why some companies choose to perform zone 1 testing while others don’t.



Zone Testing: To Do or Not to Do?Food companies use a number of factors to rationalize their

decision not to perform zone 1 testing for pathogens. Reasons

companies cite in defense of their choice to forego the testing

typically include some variation of the following:

check We’ve never done this form of testing in the past and

haven’t had any major problems yet.

check We’re worried about finding a pathogen and facing a

potential recall.

check Management doesn’t want us to find any pathogens on zone 1.

check Quality personnel may receive a bonus if nothing is found on zone 1.

check We have never been challenged by an inspector, auditor, or customer.

check We outsource this issue to our contract sanitation vendor.

check We rely on our supply chain to not send contaminated raw materials and ingredients.

check My product doesn’t support the growth of pathogens.

check My product isn’t RTE.

check Visual inspections are enough for us.

check ATP testing is sufficient for us.

check Indicator testing, (APC, Ebac, coliform, etc.) is good enough for us.

check We perform finished product testing for pathogens, so there’s no need to do zone testing.

check We react to out-of-spec results found in zone 2 by subsequently looking at nearby zone 1

surfaces.

check We can’t tell if a positive test result is due to transient contaminants or resident contaminants, so

testing is pointless.

As you can see, there are some inherent flaws in this line

of thinking. Most importantly, however, the question food

manufacturers should ask themselves is this: If pathogens on

zone 1 surfaces are your biggest food safety threat, is there

really any valid argument not to test for them?



If the aforementioned points haven’t compelled you to reconsider testing for zone 1 pathogens, here are

some additional reasons in favor of the process:

check Our product or process has been historically implicated in outbreaks caused by environmental

contamination.

check Our product is RTE, so zone 1 testing is expected by regulators, auditing schemes, and customers.

check We have a desire to test our greatest risk surfaces where food safety hazards pose the most

significant threats.

check Finished product testing is a needle-in-the-haystack approach, so the odds of finding a problem

are low.

check Indicators may be poorly correlated with pathogen prevalence.

check Too many outbreaks have occurred as a result of ignoring zone 1 testing.

check We have a desire to do robust investigational sampling to find problem hot spots.

check Past history suggests there are niches in the facility that may harbor pathogens.

check Plant construction or new equipment can dislodge pathogens from hidden harborage sites.

check We would rather have super swabbing data on hand before regulators do.

check Our product is RTE and we don’t have a kill step in our process.

check We want to measure the risk of a known GMP, sanitation, or hygiene issue.

check We don’t want to go to jail!

If you’ve begun to lean in favor of zone 1 testing by this point, the following segment will help you devise

a sound action plan for minimizing pathogen risks in your facility.



What Can Your Facility Do to Minimize Risks of Pathogens?

The FDA issued a guidance document in January of 2017 which is intended to help food companies

implement an effective EMP. It is specific to controlling listeria for RTE foods, and recommends collecting

environmental surfaces from both contact and non-contact surfaces at a time several hours into

productions and just before cleanup.

In addition to following this FDA-recommended process, here are some additional tactics to consider.

Risk-Based Corrective Actions

If you receive out-of-spec results from environmental testing, it is recommended that you ask the

following questions:

check Is the environmental contamination on a zone 1 surface or non-direct contact surface?

check Is the contamination an isolated positive, or from multiple positive results?

check What is the proximity of a contaminated non-direct contact surface to zone 1 surfaces?

check Does the food product support growth of the pathogen of concern?

These answers should help to inform your next steps.

What to Do if You Find Listeria

If listeria is discovered in your facility, perform the following steps:

check Remediate the surface by cleaning and sanitizing the area with the positive result.

check Retest during the next production cycle.

check Consider vector sampling around the contaminated area.

check Conduct a comprehensive investigation if a zone 1 surface is contaminated. This should help you

determine the root cause of the failure, and your data points should allow you to gauge how

widespread the contamination is. Is there a complete sanitation failure, a specific issue with a

GMP, or another reason behind the contamination?

check Return to routine testing if follow-up samples are negative.

If your retest results are positive for listeria, follow these steps:

check Conduct intensified cleaning and sanitizing with disassembly of zone 1 positive equipment.

check Conduct intensified sampling and testing, including vectoring around the problem site.

check Begin “product and environmental surface hold and test” if a zone 1 surface is positive and the

product supports growth. Consider this even if the food is a no-growth food as well.

check Conduct a comprehensive investigation.



What to Do if You Find Salmonella

Unlike listeria, salmonella does not need to grow directly within the food product to be a food safety risk.

Whereas listeria can establish a growth niche on environmental surfaces, salmonella is usually found due

to GMP or hygiene issues. It can exist in a state of quiescent animation when in a dry state for prolonged

periods of time. Nonetheless, despite the inherent differences among the pathogens, the corrective

actions you can take if your surface tests positive for salmonella are similar to that of listeria: seek and

destroy.

Next, we’ll assess the risks of foregoing zone 1 pathogen testing through the lens of potential scenarios

that could occur in your facility.



Zone 1 Testing: A Series of Case StudiesWhile each facility has its own unique set of risks due to differences in processes, products, and

environmental factors, the following scenarios may help illustrate why zone 1 testing is a good fit for

nearly all companies.

Case Study 1: Using ATP Swabs

Some facilities verify sanitation effectiveness using ATP monitoring of direct contact surfaces. It is a

quick and easy process, and it can be done in-house to produce real-time results. Perhaps a spec limit of

10 RLU is set.

What might happen, however, if you were to be questioned by an auditor, inspector, or customer about

the fact that ATP alone tells you little about the presence of pathogens or allergens? How would you

rebut this criticism?

Case Study 2: Mid-Shift Testing

The FDA recommends doing mid-shift EMP testing. Say your facility is a produce manufacturer, however.

There is no effective kill step in our process, and with fresh produce, there is reasonable likelihood you’re

bringing listeria on raw materials. If you perform mid-shift testing, what is the environmental data point

you derive going to tell you? If listeria is indeed brought in, how will you react to that data point?



Case Study 3: A Non-Contact Surface Pathogen Hit

If you periodically verify facility sanitation by doing pathogen testing on non-product contact surfaces,

including floors, walls, drains, and so forth, what will you do if one of those results comes back positive?

Will you simply remediate zone 2 without taking any further action in zone 1? Or, will you perform

aggressive monitoring?

You might recall a similar scenario which occurred with the outbreak of listeria stemming from Blue Bell

in 2015, to which ten confirmed cases and three deaths were linked. An investigation found that the

packaging area had condensation and an environmental contamination of listeria. While the facility was

aware of the presence of listeria due to monitoring, the corrective actions were clearly ineffective, and

they failed to do aggressive testing in zone 1 areas as well as end-product testing.

Case Study 4: A Zone 1 Pathogen Hit

In order to validate your use of indicator-only EMP testing on direct contact surfaces, you might

periodically do a pathogen test on such surfaces. If one of those results were to come back positive,

what would you do? What are the implications for the products that have come into contact with that

surface? Are you facing an entire recall scenario?

This was the situation for Sunland Foods in 2011. The 483 reports from the FDA showed four to five

successive years of factors contributing to contamination events over the same products. They were

subsequently implicated in a multistate outbreak with 42 confirmed cases of salmonella, and had to

recall products from major brands including Whole Foods, Starbucks, and Trader Joe’s. The company

now faces a lawsuit from the FDA.

Case Study 5: Super Swabbing Event

Say you are confronted by a regulatory inspection team prepared to do a super swabbing event in your

facility. Do you follow the team and swab each location they do? If so, what would you do with your

data? Even if your data isn’t the same, would there be grounds to argue with the FDA?

Of course, actions in response to these and similar scenarios are up to the discretion of each

manufacturer. Nonetheless, they are realistic situations to consider, and if they are likely to occur in your

facility, they may demand a proactive approach.

In the final section, we’ll review a response plan for out-of-spec results in zone 1 testing.



Establishing a Response Plan for Out-of-Spec Zone 1 Testing Results

If a pathogen or allergen is found in zone 1, the product that has come into contact with that surface

is considered adulterated. Thus, the first step upon discovering positive results for a pathogen is to

determine the product contamination risk. This might encompass testing and holding the product. You

might also reprocess the product using the kill step. However, if contamination is present at the kill step,

you’ll face the risk of recontamination. Depending on the circumstances, you could also destroy or divert

the product.

Next, you’ll need to increase monitoring around the contamination site to find and eliminate the source. It

is recommended that you wait until you’ve had three successive negatives before returning to the routine

sample frequency.

Corrective Actions

Here are some corrective actions to consider to address out-of-spec zone 1 testing results:

check Limit access to the area.

check Break down and inspect equipment.

check Thoroughly clean and sanitize all equipment, surfaces, and tools in the area.

check Increase sample frequency.

check Resample equipment and surfaces to determine if the contamination is localized or widespread.

check Monitor the area around the hot site to find the source.

check If the pre-op inspection fails, re-clean, re-sanitize, and re-sample as needed.

check Do not restart operations until all tests are negative.

check Achieve at least three consecutive negatives at the contamination site.

check Document all corrective actions.

check Create an SOP to prevent reoccurrence.

check If the problem persists, consider removal, replacement, or redesign of the contaminated

equipment.



Summary

Zone 1 testing is a commonly avoided aspect of environmental monitoring. It presents certain challenges

for food manufacturers; namely, the recall risk is among the most cited reasons for choosing not

to perform this type of testing. Nonetheless, ignoring your greatest risk surfaces for your greatest

food safety risk is logically flawed, and based on what we’ve seen from recent events, it could have

devastating consequences.

To review the key ideas covered within this guide, here are some actionable takeaways to consider:

check Historical data can guide the direction of your EMP, but virtually all products and environments

face some risks of contamination. Nonetheless, the primary focus for most facilities is on

controlling the risk of salmonella, listeria, and allergens.

check Testing for indicators, while popular, may fall short when it comes to identifying the presence of a

specific pathogen. While it is up to you to determine when environmental monitoring is necessary

and in which zones it will be performed, an aggressive approach is most effective for minimizing

risks.

check There are many reasons facilities choose to perform zone 1 testing – or to forego it. If your facility

hasn’t yet embraced this form of testing, consider revisiting your argument against it to see if

there are any inherent flaws in the logic used to defend your stance.

check Applying risk-based corrective actions will help your company successfully navigate any

situations in which listeria, salmonella, or allergens are discovered. You can also establish a

response plan for out-of-spec zone 1 testing with detailed corrective actions to help ensure the

safety of your product and consumers.

While zone 1 testing may require an investment of resources, saving your company from the potential

impact of a recall is well worth any time, money, or effort put into this critical activity. Having safe,

pathogen-free direct contact surfaces can save you a significant amount of stress and hassle in the long

run, and may even help you perform better in inspections and overall as a company.



About SafetyChainSafetyChain is a Quality Management System (QMS) that helps food and beverage companies improve productivity, profitability, and compliance with a flexible, user-friendly software platform that captures, manages, and analyzes real-time operations data. Learn more at https://safetychain.com.

About Eurofins Microbiology Laboratories, Inc.Eurofins Microbiology Laboratories has a mission to contribute to global health and safety by providing customers with high-quality laboratory and advisory services while creating opportunities for their employees and generating sustainable shareholder value.

About Douglas Marshall, PhD, CFSDouglas L. Marshall, PhD, CFS, Chief Scientific Officer with Eurofins Microbiology Laboratories, Inc., is a frequent consultant to NIH, WHO, FAO, USDA, and other government agencies and private companies. With over 250 publications and over 150 invited presentations, his scientific research and outreach interests focus on improving the microbiological quality and safety of foods. Dr. Marshall’s research and expertise has been featured in popular press venues such as Consumers Reports, USA Today, Fitness, Men’s Health, Chemtech, and ASM Journal Highlights.

Dr. Marshall is also co-founder and Director of the Food Safety Institute, LLC, an integrated consulting and analytical services company affiliated with Eurofins. He is a Fellow of the Institute of Food Technologists, an Inaugural Member and Chair of the International Food Science Certification Commission, and a founding member of the Global Traceability Center. He currently holds Adjunct Professor positions with Colorado State University and Florida State College.

The content of this ebrief was derived from Zone 1 Testing- Do You Dare? The Pros and Cons of Zone Approach to Testing, a SafetyChain/Eurofins Beyond Compliance webinar presented by Dr. Douglas Marshall in 2018.

zone 1 testing: do you dare? - safetychain software downloads... · 2018. 10. 24. · checkwe...

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