User Guide to Thresholds and Classification - Environmental ...

181User Guide for Thresholds and ClassificationsSchedule 4 to the Hazardous Substances (Minimum Degrees of Hazard) Regulations 2001 states:2 Minimum degrees of hazard(1) A substance with toxic properties is not hazardous for the purposes of the Act unless—…(g) data for the substance indicates a mean Draize score of 1 or more for either of the eyeirritation effects known as corneal opacity or iritis, as a result of exposure to the substance;or(h) data for the substance indicates a mean Draize score of 2 or more for either of the eyeirritation effects known as conjunctival redness or chemosis, as a result of exposure to thesubstance.12.2.2. Eye corrosion or irritation classification criteria for substancesEye corrosionSchedule 5 to the Hazardous Substances (Classification) Regulations 2001 identifies one classificationsubclass for substances that are corrosive to eyes (subclass 8.3) as follows.Subclass 8.3 – substances that are corrosive to ocular tissueA subclass 8.3 classification and the subsequent category apply to any substance that meets one of thefollowing criteria.a. A substance for which data indicate evidence in at least 33% of exposures of destruction of oculartissue, being adverse effects on the cornea, iris or conjunctiva as a result of exposure to thesubstance that are not expected to reverse or have not fully reversed within 21 days of exposure tothe substance.b. A substance for which data indicate a mean Draize score greater than or equal to 3 for cornealopacity as a result of exposure to the substance.c. A substance for which data indicate a mean Draize score greater than 1.5 for iritis as a result ofexposure to the substance.These observations include animals with grade 4 cornea lesions and other severe reactions (for example,destruction of cornea) observed at any time during the test, as well as persistent corneal opacity,discoloration of the cornea by a dye substance, adhesion, pannus, and interference with the function of theiris or other effects that impair sight. In this context, persistent lesions are considered those that are not fullyreversible within an observation period of normally 21 days.Eye irritationSchedule 4 to the Hazardous Substances Classification Regulations 2001 identifies one classificationcategory for substances that are eye irritants (subclass 6.4).Category 6.4A – substances that are irritating to the eyeA substance for which adverse effects on ocular tissue, as a result of exposure to the substance, areevidenced by data indicating a mean Draize score:January 2012 EPA0109