Welcome back again everybody to this module on applying risk assessment. In this module I will introduce you a risk assessment method and end with a practice exercise. There are a variety of different ways to do risk assessments and no one way is necessarily better than another. It really depends upon your personal preference, how much time you have and how many people are involved. I’m just going to show you one method which is semi quantitative. It’s very easy to understand and used by the World Health Organization. Let me walk you through the process now.

Here is the overall procedure. Which is similar to what was described by that cartoon character you saw in the previous module. First you identify the hazards, which is just a matter of walking around in your building, your facilities or in your laboratories and looking for those things that could do harm. Next assess the inherent risk without the controls. Then you determine what controls you need to lower that risk. Next assess the residual risk with the controls in place and finally, you monitor the controls to make sure that they are working and they’re doing the risk reduction you expect them to be doing. So that’s the overall procedure summarized. Now let’s look at each step in detail.

In the first step, you should identify the hazards and determine whether they are chemical, biological, radiological, noise, slips, trips, falls, electrical problems, or a combination. Although many hazards exist in your facility, in this course we will focus only on the biological hazards and their products. It is recognized that often chemicals are mixed in with biologics and therefore you have to also think about the chemical risks. However, the same process can also be applied to any other potential hazard (like chemicals) and any other potential risks. This risk assessment method is a very generic and universal procedure that to you can use for any risk with any hazard, even at home. As we discussed previously, start by looking at the biological hazard, what is known about it, morbidity, mortality, the host range, infectious dose, transmission routes, treatments, etc, etc.

Remember the risk groups that we talked about previously. Risk group 1-4 and how these describe inherent risk of a pathogen from low to high. Be sure you know what the pathogens are that you’re working with and be very sure that they are not been modified – they still have the same phenotype and characteristics as the traditional or base microorganisms. If it’s something that is brand new or has been modified in some way, then you have to rethink what risk group these pathogens are in.

Again, risk groups are only a starting place in your risk assessment process. If you are working with multiple pathogens from different risk groups the higher risk group would take precedence. So use risk groups as a starting place, but remember don’t stop here. Continue your risk assessment process by thinking about the procedures and practices that are being done and then who’s doing the work.

Step 2 – consider the procedures and the workers. Then determine the risk that exists without any controls, considering the consequences and likelihood of whatever adverse event you’ve identified. Once you’ve determined the likelihood and consequences you can put them into a table. First you have to put some numerical values onto the likelihood and consequences.

Start by ranking the likelihood. For the sake of this exercise, it is the likelihood of you getting infected by a pathogen while doing your routine work? Is it 1 rare; 2 unlikely; 3 possible, 4 likely or 5 almost certain? This is just one way to stratify and characterizes the likelihood. You can use a scale of 1-3 or you can use a scale of 1-10 if you like.

Now, on the consequences side, we ask the same question. If you got infected with one of the pathogens at your work, what would be the consequences of that? 1 insignificant, 2 minor, 3 moderate, 4 major or 5 catastrophic. As you can see, catastrophic, is truly that – you get death, toxic release off site and huge financial losses. You can come up with your own categories and your own definitions of these, if you want.

Once you have determined the likelihood and consequences score, you then put them into a risk matrix table, as show here. As you can see, likelihood is on the left-hand side and consequences across the top with a ranking of 1-5. Therefore, if you have a low ranking of consequences and likelihood, then the overall risk is low, as shown the light blue color. Now, if you get more moderate scores of 3 or 4 you may fall into category of moderate risk. Remember, you can determine what you consider moderate. Finally, if you have scores of 4 or 5 for likelihood or consequences, you are in the red category of high risk. Again, you can recategorize these and call them very low, low, moderately high, or extremely high. It doesn’t really matter what you call them, it’s just a matter of stratifying and trying to lump the risks together. If you multiply these scores of likelihood and consequence together, you see that the lowest score you could get is one and the highest score you could get is 25. This is quite useful, because now you can start to have good discussions about what overall risk is – unmitigated and mitigated.

The following video, summarizes some of the things I’ve said and shows you how this risk matrix can now be used in the very same fashion that I described.

I hope you enjoyed that little video. I thought it was a very nice summary of the risk assessment process risk in general and then how to use the risk matrix with some very good examples.

Once you’ve determined what the risks are you then go ahead and apply the controls for each hazard. If you have a chemical hazard, you may have a certain type of control. If you have a biological hazard, the controls may be different. In your office, there may again be different hazard that require different types of controls. Go ahead and apply the controls and determine if the controls are very good, reasonable, or poor. It may seem strange to you, but some controls just don’t work very well under certain situations. You have to make sure that the controls are indeed the correct controls and that they’re working well to minimize the risk that you’ve identified. Then you go ahead and repeat the risk assessment with the controls and fill in the table again. Hopefully what you find is a reduction in the overall risk number. For example, you’ve determined that the inherent risk without controls was moderate (score of 14), but after applying the controls, you’ve now moved the risk to something that’s low (score of three or five). So you’ve moved from 14 all the way down to 5 which means your controls are probably working pretty well and that you are mitigating the risk.

Finally, what you’re left with is called residual risk. If we use that same example as previous, you are left with five as residual risk. You need to ask yourself – is that amount of risk acceptable? If you determine it is then you move forward with the work. If you feel that’s still too much risk, then you have to apply further controls or change the controls to something that may be working better. Only if the residual risk is acceptable should you proceed with the work. It’s important to note that you will never be able to reduce risk to zero (unless you remove the hazard). We’re always going to have to accept a certain amount of risk in life. It’s just a question of – is it acceptable, under the circumstances that you’re working in. That’s why you need to have a good discussion with the entire team, because everybody is taking on that residual risk. In addition, you want to be sure to let your supervisors and senior management know that there still is risk at the workplace, and what amount that is. Ensure that it acceptable to everybody, and only if everybody agrees do you proceed with the work.

Now that you understand the overall risk assessment process, I want you to start practicing and applying these in situations that you may find yourself in. In the next slide, I’m going to show you four different scenarios in which you can practice. In each scenario, the risk is acquiring a laboratory acquired infection under the circumstances that you see described. What I want you to do for each scenario is to first identify the hazard. Then determine (in your own way) what the likelihood and consequences are of being infected by that pathogen in the situation described. Then go ahead and multiply those together which will give you a number that you can put in your risk matrix. Remember, you are going into this situation with no controls, no biosafety cabinet, no personal protective equipment. You are just working with these pathogens with your bare hands on the open bench. I know that’s a bit strange because you would never do that, but for the purposes of this exercise I just want you to think about what is the chance of you getting infected when you have no controls. After you learn the controls, we’re going to repeat this very same exercise with the controls in place. Then you can see how the controls and work to lower the risk.

Here are the four scenarios. I would appreciate it if you would work through the risk assessment for each scenario, but you’re welcome to just choose one or another if you like. The point is to start practicing doing the thought process of what is the hazard? What is the likelihood and consequences of some adverse effect adverse event happening with this pathogen that you’re working with? For example, in scenario one you’re working in a diagnostic laboratory and you’re confirming the presence of salmonella in feces. This could be human or animal feces. So the question here is – what is the likelihood and consequences of being infected with salmonella? Again, no controls – you are just working on an open bench with nothing, nothing protecting you. In scenario two you’re working in a TB lab growing cultures for long term storage. Again, what is the likelihood and consequences of you being infected under this situation using TB? In scenario three you’re working in an animal vivarium infecting chickens with the H5N1 strain of influenza, which we know can infect animals and people. What is the likelihood and consequences of you coming down with an infection under those circumstances? Finally, scenario 4 which is quite different. You’re working in the field collecting blood from people suspected of having measles. An outbreak of measles is occurring and you’ve been sent out to the field to collect blood from these people. You have no personal protective equipment, you’re just working out in the open, maybe in a hospital, maybe you’re, going into people’s homes. What is the likelihood and consequences of you contracting measles while doing this work?

These are the four scenarios that I’ve laid out for you. They’re each very different and that’s why I’d like you to take time to go ahead and do this exercise for each one of the different scenarios. What I’d like you to come up with is a number for unmitigated risk. In many cases you may see that the number is quite high, as you might expect. If you can, categorize the risk as low, moderate or high for each one of the scenarios. And again, please remember no mitigation. You’ve got no controls here. This is just the raw chance of you getting infected under these circumstances. So please take some time and do this exercise.