<SEC-DOCUMENT>0000892553-21-000100.txt : 20210909
<SEC-HEADER>0000892553-21-000100.hdr.sgml : 20210909
<ACCEPTANCE-DATETIME>20210909093530
ACCESSION NUMBER:		0000892553-21-000100
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210908
FILED AS OF DATE:		20210909
DATE AS OF CHANGE:		20210909

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Ducote Douglas A Jr.
		CENTRAL INDEX KEY:			0001863353

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-11442
		FILM NUMBER:		211243683

	MAIL ADDRESS:	
		STREET 1:		3055 TORRINGTON DRIVE
		CITY:			BALL GROUND
		STATE:			GA
		ZIP:			30107

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CHART INDUSTRIES INC
		CENTRAL INDEX KEY:			0000892553
		STANDARD INDUSTRIAL CLASSIFICATION:	FABRICATED PLATE WORK (BOILER SHOPS) [3443]
		IRS NUMBER:				341712937
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		3055 TORRINGTON DRIVE
		CITY:			BALL GROUND
		STATE:			GA
		ZIP:			30107
		BUSINESS PHONE:		770-721-8800

	MAIL ADDRESS:	
		STREET 1:		3055 TORRINGTON DRIVE
		CITY:			BALL GROUND
		STATE:			GA
		ZIP:			30107
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_163119451463387.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-09-08</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000892553</issuerCik>
        <issuerName>CHART INDUSTRIES INC</issuerName>
        <issuerTradingSymbol>GTLS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001863353</rptOwnerCik>
            <rptOwnerName>Ducote Douglas A Jr.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CHART INDUSTRIES, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>3055 TORRINGTON DRIVE</rptOwnerStreet2>
            <rptOwnerCity>BALL GROUND</rptOwnerCity>
            <rptOwnerState>GA</rptOwnerState>
            <rptOwnerZipCode>30107</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Technology Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common stock, par value $0.01 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2021-09-08</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2250</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>55.93</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8261</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common stock, par value $0.01 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2021-09-08</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2250</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>191.50</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6011</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>55.93</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2021-09-08</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2250</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2022-01-03</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common stock, par value $0.01 per share</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2250.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $191.00 to $192.51, inclusive. The reporting person undertakes to provide to Chart Industries, Inc., any security holder of Chart Industries, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.</footnote>
        <footnote id="F2">These options were granted on January 3, 2012 pursuant to the Chart Industries, Inc. 2009 Omnibus Equity Plan in an exempt transaction under Rule 16b-3. These options were fully vested.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Douglas A. Ducote, Jr., by John F. Griffee IV, his attorney-in-fact</signatureName>
        <signatureDate>2021-09-09</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
