Defendant Portland General Electric Company (PGE) petitions this court to reverse the Court of Appeals’ decision that PGE is not a “pesticide operator” as defined in ORS 634.006(13). The Court of Appeals reversed a summary judgment in favor of PGE. Vierra v. Clackamas County, 96 Or App 196, 772 P2d 1346 (1989). We affirm the decision of the Court of Appeals.
Plaintiffs brought this action to recover damages for personal injury and property damage that allegedly resulted from the escape onto their property of a pesticide that employes of PGE were spraying in the right-of-way on a public road as part of a “wire maintenance program.” The right-of-way was not PGE property.
The trial court concluded that PGE is a “pesticide operator,” as defined in ORS 634.006(13), and that plaintiffs were therefore required to, and did not, comply with the “report of loss” requirements of ORS 634.172 that are a prerequisite to bringing an action against a pesticide operator.1 ORS 634.006(13) provides:
“ ‘Pesticide operator’ means a person who owns or operates a business engaged in the application of pesticides upon the land or property of another.”
The right-of-way in this case is “the land or property of another.”
The Court of Appeals interpreted the phrase “a business engaged in the application of pesticides upon the land or property of another” to mean that “that is the person’s business, rather than something as incidental as routine equipment maintenance.” 96 Or App at 201, 772 P2d at 1348 (emphasis in original). Thus, the Court of Appeals concluded *246that PGE is not a “pesticide operator” and that the trial court erroneously granted summary judgment.
Standing alone, the definition of a “pesticide operator” under ORS 634.006(13) allows different interpretations. It could be read to say that one who is engaged in a business, any business, and applies pesticides on someone else’s land or property, escapes liability for injuring others unless the injured party files timely proof of loss with the department. Or the statute could be interpreted to apply to a business only if applying pesticides to the land of another is part of the “business” in which the defendant is “engaged.”
The Court of Appeals, in interpreting ORS 634.006(13), seemed to require that pesticide application must be a defendant’s main or principal business before the statute applies. ORS chapter 634 uses the terms “main or principal business” in other contexts. For instance, ORS 634.106(5) exempts from the statute “[p]ersons who do not advertise or publicly hold themselves out as being in the business of applying pesticides but whose main or principal work or business is the maintenance of small or home lawns, shrubs or gardens” and ORS 634.106(6) exempts “[p]ersons who do not advertise or publicly hold themselves out as being in the business of applying pesticides and whose principal activity or business as related to pesticides is selling pesticides or selling or leasing equipment.” (Emphasis added.) The exemptions show that when the drafters of this expansive environmental legislation wished to distinguish between “principal” and secondary business activities, they said so.
However, the context of the exemptions in ORS 634.106(5) and (6) shows what kind of businesses would, but for the exemption, be covered by the act: those engaged in “the business of applying pesticides,” although this is not their main or principal business and they do not advertise or hold themselves out to be in that business. The exemptions imply that someone who is not “in the business of applying pesticides” to the land of others even in a minor or secondary way (such as lawn maintenance or demonstrating pesticides or equipment) is not covered at all.
The rest of the statute bears out that “pesticide operator” refers to a type of business, not to the application of pesticides in pursuing some wholly unrelated business such as *247transmitting and selling electrical energy. A license as a “pesticide operator,” which is the object of the definition, authorizes the licensee “to engage in one or more of the classes of pest control or pesticide application business prescribed by the department under ORS 634.306(2).” ORS 634.116(1) (emphasis added.)2 The operator’s license is needed to engage in the “pesticide application business,” not in “pesticide application.”
We conclude that commercial pesticide application must at least be a part, no matter how small, of the business in which the defendant is “engaged.” One engages in the business of applying pesticides to the land or property of another if part of the earnings of one’s business comes from that source.
There is no claim that PGE is in the pesticide business in this sense. It therefore is not a “pesticide operator” under ORS 634.006(13) and cannot invoke the requirements of the proof of loss requirement.
We affirm the decision of the Court of Appeals. The judgment of the circuit court is reversed.
ORS 634.172(1) provides:
“No action against a pesticide operator, arising out of the use or application of any pesticide, shall be commenced unless the claimant has filed a report of the loss with the department, and mailed or personally delivered a true copy of such report of loss to the pesticide operator allegedly responsible and a true copy of such report to the person for whom such work was done, if other than the claimant, within 60 days from the occurrence of such loss or within 60 days from the date when the claimant discovered that such loss had occurred. If the damage is alleged to have been caused to growing crops, the report shall be filed prior to the time when 50 percent of the crop is harvested.”
Under ORS 634.306(2), the department establishes classifications of “the various pest control or pesticide application businesses in order to facilitate the licensing” of, among other things, pesticide operators. (Emphasis added.)