<?xml version="1.0" encoding="US-ASCII" ?>
    <!-- Field: Doc-Info; Name: Generator; Value: GoFiler Complete; Version: 6.4b -->
    <!-- Field: Doc-Info; Name: VendorURI; Value: https://www.novaworks.com -->
    <!-- Field: Doc-Info; Name: Status; Value: 0x00000000 -->
    <!-- Field: Doc-Info; Name: Misc; Value: 96Mps7xRiXgen8uDanwsWaKNmbP9z5Z8mekhvWBwbbkK/y0sVUSKoyIEOhHGISgK -->
<schema xmlns="http://www.w3.org/2001/XMLSchema" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xbrldi="http://xbrl.org/2006/xbrldi" xmlns:dei="http://xbrl.sec.gov/dei/2025" xmlns:us-gaap="http://fasb.org/us-gaap/2025" xmlns:srt="http://fasb.org/srt/2025" xmlns:srt-types="http://fasb.org/srt-types/2025" xmlns:ecd="http://xbrl.sec.gov/ecd/2025" xmlns:dtr-types="http://www.xbrl.org/dtr/type/2024-01-31" xmlns:RSKIA="http://grisk.com/20260131" elementFormDefault="qualified" targetNamespace="http://grisk.com/20260131">
    <annotation>
      <appinfo>
        <link:roleType roleURI="http://grisk.com/role/Cover" id="Cover">
          <link:definition>00000001 - Document - Cover</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/BalanceSheets" id="BalanceSheets">
          <link:definition>00000002 - Statement - Condensed Balance Sheets</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/BalanceSheetsParenthetical" id="BalanceSheetsParenthetical">
          <link:definition>00000003 - Statement - Condensed Balance Sheets (Parenthetical)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/IncomeStatements" id="IncomeStatements">
          <link:definition>00000004 - Statement - Condensed Income Statements (Unaudited)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/StatementsOfComprehensiveIncome" id="StatementsOfComprehensiveIncome">
          <link:definition>00000005 - Statement - Condensed Statements of Comprehensive Income (Unaudited)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/StatementsOfStockholdersEquity" id="StatementsOfStockholdersEquity">
          <link:definition>00000006 - Statement - Condensed Statements of Stockholders' Equity (Unaudited)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/StatementsOfStockholdersEquityParenthetical" id="StatementsOfStockholdersEquityParenthetical">
          <link:definition>00000007 - Statement - Condensed Statements of Stockholders' Equity (Unaudited) (Parenthetical)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/StatementsOfCashFlows" id="StatementsOfCashFlows">
          <link:definition>00000008 - Statement - Condensed Statements of Cash Flows (Unaudited)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/UnauditedInterimFinancialStatements" id="UnauditedInterimFinancialStatements">
          <link:definition>999014 - Disclosure - Unaudited Interim Financial Statements</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/Investments" id="Investments">
          <link:definition>999015 - Disclosure - Investments</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/Inventories" id="Inventories">
          <link:definition>999016 - Disclosure - Inventories</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/EarningsPerShare" id="EarningsPerShare">
          <link:definition>999017 - Disclosure - Earnings per Share</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/RetirementBenefitPlan" id="RetirementBenefitPlan">
          <link:definition>999018 - Disclosure - Retirement Benefit Plan</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/FairValueMeasurements" id="FairValueMeasurements">
          <link:definition>999019 - Disclosure - Fair Value Measurements</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/SubsequentEvents" id="SubsequentEvents">
          <link:definition>999020 - Disclosure - Subsequent Events</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/UnauditedInterimFinancialStatementsPolicies" id="UnauditedInterimFinancialStatementsPolicies">
          <link:definition>999021 - Disclosure - Unaudited Interim Financial Statements (Policies)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/InvestmentsTables" id="InvestmentsTables">
          <link:definition>999022 - Disclosure - Investments (Tables)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/InventoriesTables" id="InventoriesTables">
          <link:definition>999023 - Disclosure - Inventories (Tables)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/EarningsPerShareTables" id="EarningsPerShareTables">
          <link:definition>999024 - Disclosure - Earnings per Share (Tables)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/FairValueMeasurementsTables" id="FairValueMeasurementsTables">
          <link:definition>999025 - Disclosure - Fair Value Measurements (Tables)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/UnauditedInterimFinancialStatementsDetailsNarrative" id="UnauditedInterimFinancialStatementsDetailsNarrative">
          <link:definition>999026 - Disclosure - Unaudited Interim Financial Statements (Details Narrative)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/ScheduleOfInvestmentsDetails" id="ScheduleOfInvestmentsDetails">
          <link:definition>999027 - Disclosure - Schedule of Investments (Details)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/ScheduleOfUnrealizedLossBreakdownByInvestmentTypeDetails" id="ScheduleOfUnrealizedLossBreakdownByInvestmentTypeDetails">
          <link:definition>999028 - Disclosure - Schedule of Unrealized Loss Breakdown by Investment Type (Details)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/InvestmentsDetailsNarrative" id="InvestmentsDetailsNarrative">
          <link:definition>999029 - Disclosure - Investments (Details Narrative)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/ScheduleOfInventoriesDetails" id="ScheduleOfInventoriesDetails">
          <link:definition>999030 - Disclosure - Schedule of Inventories (Details)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/ScheduleOfBasicAndDilutedEarningsPerShareDetails" id="ScheduleOfBasicAndDilutedEarningsPerShareDetails">
          <link:definition>999031 - Disclosure - Schedule of Basic and Diluted Earnings Per Share (Details)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/RetirementBenefitPlanDetailsNarrative" id="RetirementBenefitPlanDetailsNarrative">
          <link:definition>999032 - Disclosure - Retirement Benefit Plan (Details Narrative)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:roleType roleURI="http://grisk.com/role/ScheduleOfAssetsMeasuredAtFairValueOnRecurringBasisDetails" id="ScheduleOfAssetsMeasuredAtFairValueOnRecurringBasisDetails">
          <link:definition>999033 - Disclosure - Schedule of Assets Measured at Fair Value on Recurring Basis (Details)</link:definition>
          <link:usedOn>link:presentationLink</link:usedOn>
          <link:usedOn>link:calculationLink</link:usedOn>
          <link:usedOn>link:definitionLink</link:usedOn>
        </link:roleType>
        <link:linkbaseRef xlink:type="simple" xlink:href="rskia-20260131_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Presentation Links" />
        <link:linkbaseRef xlink:type="simple" xlink:href="rskia-20260131_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Label Links" />
        <link:linkbaseRef xlink:type="simple" xlink:href="rskia-20260131_cal.xml" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Calculation Links" />
        <link:linkbaseRef xlink:type="simple" xlink:href="rskia-20260131_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Definition Links" />
      </appinfo>
    </annotation>
    <import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
    <import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" />
    <import namespace="http://xbrl.sec.gov/dei/2025" schemaLocation="https://xbrl.sec.gov/dei/2025/dei-2025.xsd" />
    <import namespace="http://fasb.org/us-gaap/2025" schemaLocation="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd" />
    <import namespace="http://fasb.org/us-types/2025" schemaLocation="https://xbrl.fasb.org/us-gaap/2025/elts/us-types-2025.xsd" />
    <import namespace="http://www.xbrl.org/dtr/type/2024-01-31" schemaLocation="https://www.xbrl.org/dtr/type/2024-01-31/types.xsd" />
    <import namespace="http://xbrl.sec.gov/ecd/2025" schemaLocation="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd" />
    <import namespace="http://xbrl.sec.gov/country/2025" schemaLocation="https://xbrl.sec.gov/country/2025/country-2025.xsd" />
    <import namespace="http://fasb.org/srt/2025" schemaLocation="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd" />
    <import namespace="http://fasb.org/srt-types/2025" schemaLocation="https://xbrl.fasb.org/srt/2025/elts/srt-types-2025.xsd" />
    <element id="RSKIA_ClassCommonStock0.10ParValueMember" name="ClassCommonStock0.10ParValueMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_ConvertiblePreferredStock20StatedValueMember" name="ConvertiblePreferredStock20StatedValueMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_CommonStockClassAMember" name="CommonStockClassAMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_TreasuryStockCommonClassAMember" name="TreasuryStockCommonClassAMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_MoneyMarketsAndCDsMember" name="MoneyMarketsAndCDsMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_MoneyMarketsMember" name="MoneyMarketsMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_IncomeTaxOverpaymentCurrent" name="IncomeTaxOverpaymentCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_FederalSolarTaxCreditReceivable" name="FederalSolarTaxCreditReceivable" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_EngineeringExpenses" name="EngineeringExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_GainLossOnSolarTaxCredit" name="GainLossOnSolarTaxCredit" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_IncreaseDecreaseFederalSolarTaxCreditReceivable" name="IncreaseDecreaseFederalSolarTaxCreditReceivable" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_IncreaseDecreaseInIncomeTaxOverpayment" name="IncreaseDecreaseInIncomeTaxOverpayment" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_IncreaseDecreaseDeferredGainOnSolarTaxCredit" name="IncreaseDecreaseDeferredGainOnSolarTaxCredit" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_CashPaymentForAbstract" name="CashPaymentForAbstract" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_CashReceiptsForAbstract" name="CashReceiptsForAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_IncomeTaxesReceipts" name="IncomeTaxesReceipts" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_NoInsiderTradingFlag" name="NoInsiderTradingFlag" nillable="true" xbrli:periodType="duration" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_PurchaseOfTransferrableTaxCreditsPolicyTextBlock" name="PurchaseOfTransferrableTaxCreditsPolicyTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_ScheduleOfUnrealizedLossOnInvestmentTableTextBlock" name="ScheduleOfUnrealizedLossOnInvestmentTableTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_ImpairmentOfInvestment" name="ImpairmentOfInvestment" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="RSKIA_IncrementalCommonSharesAttributableToConversionOfPreferredStockPerShare" name="IncrementalCommonSharesAttributableToConversionOfPreferredStockPerShare" nillable="true" xbrli:periodType="duration" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
</schema>
