Air Emission Management for MSS EventsThere are a few times in the year when your air emissions compliance is most at risk, since they can be the most difficult to control and anticipate: these are your maintenance, startup, and shutdown (MSS) events. They are the three most common types of events you’ll experience that just do not fit in with your normal, everyday operations.

    Regulators typically categorize MSS events as those activities that directly affect the smooth operations of your equipment and processes and are not part of your everyday operations. For example, a routine tune up for your boiler once a year would be considered a planned maintenance event.

    The challenge with MSS events is that you are still responsible for managing the associated HAP and VOC air emissions, even when things get out of hand. This means ensuring your emissions do not exceed your limits, that any problems get corrected as soon as possible, and that everything gets accurately documented. All in all, MSS events are a lot of high-pressure work for environmental managers.

    We’ve prepared this short primer for anyone looking to learn more about MSS events as they relate to manufacturing. MSS regulations do differ from state to state, so it’s important to always double check what your local regulations are with your state compliance agents.

    Planned & Unplanned MSS Events

    MSS events are a normal part of the manufacturing process, although often they are not considered to be the “standard operation” of your equipment and processes. However, the EPA does require your facility’s air emission limits and thresholds to be in effect during MSS events.

    There are two types of MSS event: planned and unplanned. Although this may seem obvious, the way the regulators approach them is very different. Planned MSS events are those activities that you undertake deliberately and schedule well in advance. Usually this also means three’s a pattern or calculated timing for the MSS event to occur (for example, a standard planned MSS event would occur every 6 months / after 10,000 hours of operation / once per shift). Keep in mind that janitorial duties, like fixing a leaking roof or repaving a facility’s parking lot do not fall into the MSS event category.

    It’s important to note that when planning your MSS events for the year, you do not need to calculate the exact hour or day these occurrences will fall on.  There’s no need to sit down and figure out what day the 10,000th hour of operations will fall on.

    It is important, however, to plan these MSS events in advance because most regulators do require you to notify them in writing or even get these planned MSS events authorized before they occur. The best way to keep abreast of this is to keep in touch with your local regulator, as they will know if a planning/authorization deadline is approaching. For example, all manufacturers in the State of Texas (except the oil & gas industry) have to submit authorizations for their 2013 planned MSS events to the Texas Commission on Environmental Quality by January 5, 2013.

    Unplanned MSS events, in contrast, are those unexpected shutdowns or equipment malfunctions that you cannot possibly plan for. These moments carry the most risk and are more likely to do damage to your environmental compliance management, especially if they go unnoticed until you’ve already reached an air emissions limit. Since these MSS events are unanticipated, there is no paperwork that needs to get done beforehand – however, there is a mountain of paperwork waiting for you once the event is over.

    In particular, it’s very important that you keep close track of the type and quantity of fugitive air emissions that occur during the MSS event. It’s also essential that any corrective actions that get taken get carefully documented and time-stamped, since you’ll need to prove to the EPA that you took action as quickly as possible. We’ve written extensively about this issue over on Environmental Leader as well.

    Getting Planned MSS Events Authorized

    If your facility is required to submit an authorization form for your planned MSS activities, it is vital that you contact your local environmental regulatory office and find out the exact procedure for doing so, as well as any approaching deadlines that could affect your industry. Because the procedure for authorization is different for every state, the only guaranteed way to get informed about MSS policies for your facility is to ask your regulator.

    ERA does, however, have this time-saving tip to pass along:

    Check to see if your operating permit(s) already include all your planned MSS events. If this is the case you may not have to submit a whole new authorization form (again, this applies to some states and not others). For example, if your facility’s Permit By Rule (PBR) authorizes your planned MSS events, you may not need to take any further action. In other cases, having MSS events approved by an air permit may not be enough to avoid the need to submit an authorization request.

    If you are not 100% sure of your MSS standing (permits can be incredibly dense, after all) the best course of action is to talk to your regulator and undertake the authorization process anyways.

    Why Authorization & Planning is Important

    If your facility fails to get MSS events authorized according to your local air emissions regulations, you could be putting your environmental compliance at serious risk. Specifically, you will not be protected from penalties during unavoidable and unanticipated malfunctions under the Affirmative Defense, a report that helps responsible manufacturers and protects them from hefty fines. If there was nothing anyone could do to avoid a compliance breach because of an unplanned MSS event (usually a serious malfunction of control equipment), the Affirmative Defense shields the facility from accruing fines. However, the only way to prove this was an unplanned event was to have already gotten your planned MSS events approved or to have notified your regulators.

    Make it a  priority before the year is over to check in on whether MSS event authorization will affect your facility in the coming year. The deadlines could be sooner than you expect.

    We recently published a short guide for Texas Manufacturers approaching the January 5, 2013 authorization deadline. Get a free copy here.

    This Blog was Co-Authored By:


    Alex Chamberlain
    Post by Alex Chamberlain
    January 3, 2013
    Alex Chamberlain is a writer for ERA Environmental Management Solutions.