Housekeeping: A Gentlemen's Agreement
The most significant provision in 61B is the basic housekeeping requirement. Unlike the standard later adopted by OSHA, which contains specific action levels and alternatives for dust control, 61B dispenses with the topic by stating simply that "dust shall be removed concurrently with operations." This language has been known to provoke a good laugh from Agricultural Dusts committee members pressed to explain what it really means.
Whatever it means, the provision is not enforceable. OSHA learned that when it tried to use 61B in support of citations issued after the 1977 explosions. The commission that reviews OSHA citations was unwilling to rely on such an ambiguous provisions. In actuality, the housekeeping provision is not a "requirement" at all. It is more of a gentlemen's agreement to recognize the problem but leave its solution entirely to the individual operator. "I think that you have to consider that people are going to be reasonable and rational about applying this," explained a Continental Grain representative at an OSHA hearing.
Whether a more specific requirement would be desirable is the subject of considerable controversy. Leaving that question aside for the moment, the lack of specificity of the housekeeping requirement in 61B is not adequately justified by the reasons most commonly offered in its defense. "If someone can tell us how to be more specific and be scientifically logical" in establishing dust-control requirements, explains an Agricultural Dusts committee member from a major grain company, "we would buy it." Indeed, there is no way to do so—short of banning grain dust—if "scientific logic" demands total safety. Research sponsored by the NGFA indicates that a dust layer as thin as one-hundredth of an inch can propagate an explosion. The NGFA has been accused by its detractors of conducting this research precisely to bolster the "scientific" argument against any standard. But there rarely is a strong
scientific basis for resolving complex problems involving the trade-off between cost and safety. If this call for greater scientific certainty applied equally to all standards-setting, it would largely paralyze the effort. There are too many variables interacting and changing over time to expect anything resembling scientific certainty for each one.
Guesses, commonsense judgments, and just plain arbitrary numbers adorn public and private standards alike. They have to. NFPA 61B is no exception. The requirement that grain driers be cleaned every 168 hours, for example, is not scientifically logical. As it turns out, 168 was chosen because that is how many hours there are in a week—a measure no more scientific than Continental Grain's policy of cleaning them every 48 hours. Limiting the temperature of hot pipes to 160° F, prohibiting more than 25 percent of a roof from being plastic panel, and suggesting that motor-driven equipment be cleaned at one-hour intervals during operations are further examples of provisions in 61B that are equally susceptible to the charge of scientific infirmity. In each case, the number is an admittedly arbitrary one, based on the consensus of committee members as to what constitutes a reasonable requirement.
In fact, scientific uncertainty did not prevent Continental Grain or the Factory Mutual Corporation from incorporating an "action level" of one-eight of an inch of layered dust into their own in-house standards for housekeeping. So why does the NFPA Agricultural Dusts committee demand more of science? One possible reason is that the dust-control problem is more complicated than most issues. Hot pipes present similar hazards under a variety of circumstances; grain dust does not. Dust hazards depend, to some degree, on virtually every aspect of a grain-handling facility, including the product it handles, its sales and operation patterns, the general layout and date of design, and the effectiveness of existing dust-control equipment. In short, some facilities have much less need or ability than others to conduct housekeeping. The image of the "small country elevator"—a mom-and-pop operation with no hired hands, but a line of anxious farmers waiting to unload their grain before it starts raining—is often evoked in this line of argument. Some country elevators have little need for dust control because they have low throughput and no enclosed bucket elevators. Others, it is argued, lack the resources to purchase dust collection systems or hire additional labor. The appropriate action level, if there is such a thing, varies significantly by facility, and the small ones should, the argument continues, be spared the regulatory rod entirely.
This position on dust control contradicts the position taken else-
where in 61B. The Agricultural Dusts committee has gone on record several times against the notion that differences in facilities render a general standard inappropriate. Separate NFPA standards for country elevators were combined with those for other grain-handling facilities in 1973, when the committee decided that "a distinction between types of grain elevators on the basis of capacity or shipping or receiving media is no longer practical." Similarly, a committee member argued in July 1985 that motion switches should not be mandated on all bucket elevator legs because some country elevators "do not realistically need them." The committee rejected the argument on the grounds that motion switches were generally a good idea and it would be impossible to identify in a standard those situations in which they are not necessary. The same could be said about dust-control requirements. "Facilities vary," notes a former USDA investigator, "but the hazard scenarios are the same."