diff --git a/package.json b/package.json
index 918ab581..4050f5e3 100644
--- a/package.json
+++ b/package.json
@@ -18,7 +18,7 @@
 		"start": "polymer serve -o",
 		"postinstall": "polymer install --variants",
 		"lint": "eslint --cache --ext .js,.html . && polymer lint cosmoz-*.html",
-		"test": "TZ=Europe/Bucharest polymer test",
+		"test": "polymer test",
 		"analyze": "polymer analyze --input cosmoz-*.html  > analysis.json"
 	},
 	"repository": {
diff --git a/test/.eslintrc.json b/test/.eslintrc.json
index 328c2ce3..1f335c91 100644
--- a/test/.eslintrc.json
+++ b/test/.eslintrc.json
@@ -12,6 +12,14 @@
 		"flush": false,
 		"MockInteractions": false,
 		"sinon": true,
-		"WCT": false
+		"WCT": false,
+		"getDomType": false,
+		"setupOmnitableFixture":false
+	},
+	"rules": {
+		"no-unused-vars": [
+			"warn",
+			{"varsIgnorePattern":"omnitable"}
+		]
 	}
 }
diff --git a/test/basic.html b/test/basic.html
index 6c1b19b7..dbea4877 100644
--- a/test/basic.html
+++ b/test/basic.html
@@ -8,10 +8,10 @@
 	<script src="../../webcomponentsjs/webcomponents-lite.js"></script>
 	<script src="../../web-component-tester/browser.js"></script>
 	<script src="../../test-fixture/test-fixture-mocha.js"></script>
+	<script src="./helpers/utils.js"></script>
 
 	<link rel="import" href="../../test-fixture/test-fixture.html">
 	<link rel="import" href="../../iron-test-helpers/iron-test-helpers.html">
-	<link rel="import" href="helpers.html">
 	<link rel="import" href="../cosmoz-omnitable.html">
 	<link rel="import" href="../cosmoz-omnitable-columns.html">
 	<link rel="import" href="../demo/table-demo-behavior.html">
@@ -53,10 +53,11 @@
 
 	<script>
 	(function () {
-		/* global setupOmnitableFixture*/
 		'use strict';
 
-		suite('basic', function () {
+		const domType = getDomType();
+
+		suite('basic' + domType, () => {
 			var omnitable,
 				data;
 
@@ -208,7 +209,7 @@
 			});
 		});
 
-		suite('it logs unnamed column', function () {
+		suite('it logs unnamed column' + domType, () => {
 			var omnitable,
 				data,
 				consoleErrorStub;
diff --git a/test/boolean.html b/test/boolean.html
index 6599305c..1bbde933 100644
--- a/test/boolean.html
+++ b/test/boolean.html
@@ -8,10 +8,10 @@
 	<script src="../../webcomponentsjs/webcomponents-lite.js"></script>
 	<script src="../../web-component-tester/browser.js"></script>
 	<script src="../../test-fixture/test-fixture-mocha.js"></script>
+	<script src="./helpers/utils.js"></script>
 
 	<link rel="import" href="../../test-fixture/test-fixture.html">
 	<link rel="import" href="../../iron-test-helpers/iron-test-helpers.html">
-	<link rel="import" href="helpers.html">
 	<link rel="import" href="../cosmoz-omnitable.html">
 	<link rel="import" href="../cosmoz-omnitable-columns.html">
 	<link rel="import" href="../demo/table-demo-behavior.html">
@@ -28,10 +28,11 @@
 
 	<script>
 	(function () {
-		/* global setupOmnitableFixture*/
 		'use strict';
 
-		suite('basic', () => {
+		const domType = getDomType();
+
+		suite('basic' + domType, () => {
 			let omnitable,
 				column,
 				data;
diff --git a/test/fit-dropdowns.html b/test/fit-dropdowns.html
index 5ffffe75..77f267d5 100644
--- a/test/fit-dropdowns.html
+++ b/test/fit-dropdowns.html
@@ -8,10 +8,10 @@
 		<script src="../../webcomponentsjs/webcomponents-lite.js"></script>
 		<script src="../../web-component-tester/browser.js"></script>
 		<script src="../../test-fixture/test-fixture-mocha.js"></script>
+		<script src="./helpers/utils.js"></script>
 
 		<link rel="import" href="../../test-fixture/test-fixture.html">
 		<link rel="import" href="../../iron-test-helpers/iron-test-helpers.html">
-		<link rel="import" href="helpers.html">
 		<link rel="import" href="../cosmoz-omnitable.html">
 		<link rel="import" href="../cosmoz-omnitable-column-autocomplete.html">
 		<link rel="import" href="../cosmoz-omnitable-column.html">
@@ -35,12 +35,13 @@
 				</cosmoz-omnitable>
 			</template>
 		</test-fixture>
-
 		<script>
 		(function () {
-			/* global setupOmnitableFixture*/
+			'use strict';
+
 			let omnitable;
-			const data = [
+			const domType = getDomType(),
+				data = [
 					{ id: 0, group: 'group0', name: 'Item 0' },
 					{ id: 1, group: 'group0', name: 'Item 1' },
 					{ id: 2, group: 'group1', name: 'Item 2' },
@@ -50,7 +51,7 @@
 					omnitable = setupOmnitableFixture('basic', data, () => done());
 				};
 
-			suite('fit-dropdowns', () => {
+			suite('fit-dropdowns' + domType, () => {
 				test('sets iron-dropdown fitInto property', done => {
 					instantiate(() => {
 						[
@@ -67,7 +68,7 @@
 				});
 			});
 
-			suite('autocomplete unit tests', () => {
+			suite('autocomplete unit tests' + domType, () => {
 				test('getComparableValue returns value converted to String', done => {
 					instantiate(() => {
 						const column = omnitable.columns[0];
diff --git a/test/group.html b/test/group.html
index 58d2e030..cdb70308 100644
--- a/test/group.html
+++ b/test/group.html
@@ -8,10 +8,10 @@
 	<script src="../../webcomponentsjs/webcomponents-lite.js"></script>
 	<script src="../../web-component-tester/browser.js"></script>
 	<script src="../../test-fixture/test-fixture-mocha.js"></script>
+	<script src="./helpers/utils.js"></script>
 
 	<link rel="import" href="../../test-fixture/test-fixture.html">
 	<link rel="import" href="../../iron-test-helpers/iron-test-helpers.html">
-	<link rel="import" href="helpers.html">
 	<link rel="import" href="../cosmoz-omnitable.html">
 	<link rel="import" href="../cosmoz-omnitable-columns.html">
 	<link rel="import" href="../demo/table-demo-behavior.html">
@@ -72,10 +72,11 @@
 
 	<script>
 	(function () {
-		/* global setupOmnitableFixture*/
 		'use strict';
 
-		suite('id', () => {
+		const domType = getDomType();
+
+		suite('id' + domType, () => {
 			let omnitable,
 				data;
 
@@ -119,7 +120,7 @@
 			});
 		});
 
-		suite('bool', () => {
+		suite('bool' + domType, () => {
 			let omnitable,
 				data;
 
@@ -148,37 +149,36 @@
 				}, 120);
 			});
 		});
-	}());
 
-	suite('amount', () => {
-		let omnitable,
-			data;
-
-		setup(done => {
-			data = Cosmoz.TableDemoBehavior.generateTableDemoData(10, 11, 25);
-			omnitable = setupOmnitableFixture('amount', data, () => done());
-		});
+		suite('amount' + domType, () => {
+			let omnitable,
+				data;
 
-		test('setting groupOn property to "amount" updates property groupOnColumn', done => {
-			omnitable.groupOn = 'amount';
+			setup(done => {
+				data = Cosmoz.TableDemoBehavior.generateTableDemoData(10, 11, 25);
+				omnitable = setupOmnitableFixture('amount', data, () => done());
+			});
 
-			omnitable.notifyResize();
-			const verifyColumn = () => {
-				const groupOnColumn = omnitable.groupOnColumn;
-				if (groupOnColumn == null) {
-					Polymer.Base.async(verifyColumn, 50);
-				} else {
-					assert.equal(typeof groupOnColumn, 'object');
-					assert.equal(groupOnColumn.is, 'cosmoz-omnitable-column-amount');
-					assert.equal(groupOnColumn.name, 'amount', 'Expected "groupOnColumn" to be the column that matches "groupOn" value');
-					assert.equal(groupOnColumn, omnitable.columns[0]);
-					done();
-				}
-			};
-			Polymer.Base.async(verifyColumn, 50);
+			test('setting groupOn property to "amount" updates property groupOnColumn', done => {
+				omnitable.groupOn = 'amount';
+
+				omnitable.notifyResize();
+				const verifyColumn = () => {
+					const groupOnColumn = omnitable.groupOnColumn;
+					if (groupOnColumn == null) {
+						Polymer.Base.async(verifyColumn, 50);
+					} else {
+						assert.equal(typeof groupOnColumn, 'object');
+						assert.equal(groupOnColumn.is, 'cosmoz-omnitable-column-amount');
+						assert.equal(groupOnColumn.name, 'amount', 'Expected "groupOnColumn" to be the column that matches "groupOn" value');
+						assert.equal(groupOnColumn, omnitable.columns[0]);
+						done();
+					}
+				};
+				Polymer.Base.async(verifyColumn, 50);
+			});
 		});
-	});
-
 
+	}());
 	</script>
 </body></html>
diff --git a/test/hash-param.html b/test/hash-param.html
index 6319956f..74ff7624 100644
--- a/test/hash-param.html
+++ b/test/hash-param.html
@@ -8,11 +8,10 @@
 		<script src="../../webcomponentsjs/webcomponents-lite.js"></script>
 		<script src="../../web-component-tester/browser.js"></script>
 		<script src="../../test-fixture/test-fixture-mocha.js"></script>
+		<script src="./helpers/utils.js"></script>
 
 		<link rel="import" href="../../test-fixture/test-fixture.html">
 		<link rel="import" href="../../iron-test-helpers/iron-test-helpers.html">
-		<link rel="import" href="helpers.html">
-
 		<link rel="import" href="../cosmoz-omnitable.html">
 		<link rel="import" href="../cosmoz-omnitable-column-autocomplete.html">
 		<link rel="import" href="../cosmoz-omnitable-column.html">
@@ -39,9 +38,11 @@
 
 		<script>
 		(function () {
-			/* global setupOmnitableFixture*/
+			'use strict';
+
 			let omnitable;
-			const data = [
+			const domType = getDomType(),
+				data = [
 					{ id: 0, group: 'group0', name: 'Item 0' },
 					{ id: 1, group: 'group0', name: 'Item 1' },
 					{ id: 2, group: 'group1', name: 'Item 2' },
@@ -52,7 +53,7 @@
 					omnitable = setupOmnitableFixture('basic', data, () => done());
 				};
 
-			suite('basic-read', function () {
+			suite('basic-read' + domType, () => {
 				teardown(function (done) {
 					location.hash = '';
 					done();
@@ -96,7 +97,7 @@
 				});
 			});
 
-			suite('basic-write', function () {
+			suite('basic-write' + domType, () => {
 				setup(instantiate);
 				teardown(function (done) {
 					location.hash = '';
diff --git a/test/helpers.html b/test/helpers.html
deleted file mode 100644
index 8908a9de..00000000
--- a/test/helpers.html
+++ /dev/null
@@ -1,30 +0,0 @@
-<script>
-(function () {
-	/* global window */
-	'use strict';
-
-	window.setupOmnitableFixture = function (omnitableFixtureName, data, callback) {
-		const omnitable = fixture(omnitableFixtureName);
-		omnitable.data = data;
-		if (omnitable.visibleColumns != null && omnitable.visibleColumns.length) {
-			callback(omnitable);
-		} else {
-			// In Polymer 1.x, the visible-columns-changed event will be fire multiple times,
-			// causing done to be called multiple times, which mocha does not allow.
-			// So using a flag to prevent multiple calls to done.
-			const onVisible = () => {
-				const columns = omnitable.visibleColumns;
-				if (Array.isArray(columns) && columns.length > 0) {
-					omnitable.removeEventListener('visible-columns-changed', onVisible);
-					Polymer.Base.async(() => callback(omnitable), 60);
-				}
-			};
-
-			omnitable.addEventListener('visible-columns-changed', onVisible);
-		}
-
-		omnitable.notifyResize();
-		return omnitable;
-	};
-}());
-</script>
diff --git a/test/helpers/utils.js b/test/helpers/utils.js
new file mode 100644
index 00000000..bc008fb8
--- /dev/null
+++ b/test/helpers/utils.js
@@ -0,0 +1,55 @@
+(function () {
+	'use strict';
+
+	const setupOmnitableFixture = (omnitableFixtureName, data, callback) => {
+		const omnitable = fixture(omnitableFixtureName);
+		omnitable.data = data;
+		if (omnitable.visibleColumns != null && omnitable.visibleColumns.length) {
+			callback(omnitable);
+		} else {
+			// In Polymer 1.x, the visible-columns-changed event will be fire multiple times,
+			// causing done to be called multiple times, which mocha does not allow.
+			// So using a flag to prevent multiple calls to done.
+			const onVisible = () => {
+				const columns = omnitable.visibleColumns;
+				if (Array.isArray(columns) && columns.length > 0) {
+					omnitable.removeEventListener('visible-columns-changed', onVisible);
+					Polymer.Base.async(() => callback(omnitable), 60);
+				}
+			};
+
+			omnitable.addEventListener('visible-columns-changed', onVisible);
+		}
+
+		omnitable.notifyResize();
+		return omnitable;
+	};
+
+	// Detect dom type: dom=shadow vs wc-shadydom=true
+	const getDomType = () => {
+		// match GET parameter named 'dom'
+		let param = window.location.search.match(/(\?|&)dom\=([^&]*)/), // eslint-disable-line no-useless-escape
+			dom;
+		if (Array.isArray(param) && param.length > 0) {
+			dom = decodeURIComponent(param[2]);
+		}
+		const domType = dom && dom === 'shadow' ? ' | Using shadow DOM' : ' | Using shady DOM';
+		return domType;
+	};
+
+	const onColumnReady = (omnitable, columnIndex, done) => {
+		const checkReady = () => {
+			const {visibleColumns: visible, columns} = omnitable;
+			if (visible && visible.length > 0) {
+				omnitable.removeEventListener('visible-columns-changed', checkReady);
+				Polymer.Base.async(() => done(columns[columnIndex]), 30);
+			}
+		};
+		omnitable.addEventListener('visible-columns-changed', checkReady);
+		omnitable.notifyResize();
+		checkReady();
+	};
+
+	Object.assign(window, {setupOmnitableFixture, getDomType, onColumnReady});
+}());
+
diff --git a/test/list.html b/test/list.html
index 6a85b3cc..a03c8156 100644
--- a/test/list.html
+++ b/test/list.html
@@ -8,10 +8,10 @@
 	<script src="../../webcomponentsjs/webcomponents-lite.js"></script>
 	<script src="../../web-component-tester/browser.js"></script>
 	<script src="../../test-fixture/test-fixture-mocha.js"></script>
+	<script src="./helpers/utils.js"></script>
 
 	<link rel="import" href="../../test-fixture/test-fixture.html">
 	<link rel="import" href="../../iron-test-helpers/iron-test-helpers.html">
-	<link rel="import" href="helpers.html">
 	<link rel="import" href="../cosmoz-omnitable.html">
 	<link rel="import" href="../cosmoz-omnitable-columns.html">
 	<link rel="import" href="../demo/table-demo-behavior.html">
@@ -36,10 +36,12 @@
 
 	<script>
 	(function () {
-		/* global setupOmnitableFixture*/
 		'use strict';
 
-		suite('basic', () => {
+		// get dom Type from helpers.js
+		const domType = getDomType();
+
+		suite('basic' + domType, () => {
 			let omnitable,
 				column,
 				data;
@@ -87,7 +89,7 @@
 			});
 
 		});
-		suite('horizontal', () => {
+		suite('horizontal' + domType, () => {
 			let omnitable,
 				column,
 				data;
diff --git a/test/range-date.html b/test/range-date.html
index ef674ee2..ee7200e6 100644
--- a/test/range-date.html
+++ b/test/range-date.html
@@ -8,10 +8,10 @@
 	<script src="../../webcomponentsjs/webcomponents-lite.js"></script>
 	<script src="../../web-component-tester/browser.js"></script>
 	<script src="../../test-fixture/test-fixture-mocha.js"></script>
+	<script src="./helpers/utils.js"></script>
 
 	<link rel="import" href="../../test-fixture/test-fixture.html">
 	<link rel="import" href="../../iron-test-helpers/iron-test-helpers.html">
-	<link rel="import" href="helpers.html">
 	<link rel="import" href="../cosmoz-omnitable.html">
 	<link rel="import" href="../cosmoz-omnitable-columns.html">
 	<link rel="import" href="../demo/table-demo-behavior.html">
@@ -35,42 +35,62 @@
 	</test-fixture>
 
 	<script>
-	/*global sinon chai flush setupOmnitableFixture*/
 	(function () {
 		'use strict';
-		const data = [
-			{ age: 17,
-				amount: { amount: '12.4', currency: 'USD' },
-				date: '2023-03-21T00:00:00Z',
-				time: ''
-			},
-			{ amount: { amount: 2 },
-				date: new Date('2015-03-18T00:00:00Z')
-			},
-			{ age: -11,
-				amount: { amount: 678, currency: 'AUD' },
-				date: new Date(86400000), // Fri Jan 02 1970
-				time: 86400000
-			},
-			{ age: 9,
-				amount: { amount: -8, currency: 'EUR' },
-				date: new Date(99, 5, 24, 11, 33, 30, 0), // Thu Jun 24 1999 11:33:30 GMT+0300 (EEST)
-				time: '86400000'
-			},
-			{
-				age: 5,
-				amount: { amount: '3450', currency: 'DKK' },
-				date: new Date('2016-08-27'),
-				time: '2016-08-27T14:34:56Z'
-			},
-			{
-				date: '2017-12-22T23:00:00Z'
-			}
-		];
+
+		const domType = getDomType(),
+			data = [
+				{ age: 17,
+					amount: { amount: '12.4', currency: 'USD' },
+					date: '2023-03-21T00:00:00Z',
+					time: ''
+				},
+				{ amount: { amount: 2 },
+					date: new Date('2015-03-18T00:00:00Z')
+				},
+				{ age: -11,
+					amount: { amount: 678, currency: 'AUD' },
+					date: new Date(86400000), // Fri Jan 02 1970
+					time: 86400000
+				},
+				{ age: 9,
+					amount: { amount: -8, currency: 'EUR' },
+					date: new Date(99, 5, 24, 11, 33, 30, 0), // Thu Jun 24 1999 11:33:30 GMT+0300 (EEST)
+					time: '86400000'
+				},
+				{
+					age: 5,
+					amount: { amount: '3450', currency: 'DKK' },
+					date: new Date('2016-08-27'),
+					time: '2016-08-27T14:34:56Z'
+				},
+				{
+					date: '2017-12-22T23:00:00Z',
+					time: '00:00:00'
+				}
+			];
+
+		const onFilter = (column, done) => {
+			let handler;
+			column.addEventListener('filter-changed', handler = () => {
+				column.removeEventListener('filter-changed', handler);
+				done();
+			});
+		};
+
+		const onFilterItems = (omnitable, column, done) => {
+			onFilter(column, () => {
+				let handler;
+				omnitable.addEventListener('sorted-filtered-grouped-items-changed', handler = () => {
+					done(omnitable.sortedFilteredGroupedItems);
+					omnitable.removeEventListener('sorted-filtered-grouped-items-changed', handler);
+				});
+			});
+		};
 
 		sinon.assert.expose(chai.assert, { prefix: '' });
 
-		suite('date', function () {
+		suite('date' + domType, () => {
 			let omnitable,
 				column;
 
@@ -125,26 +145,35 @@
 			});
 
 			test('_toLocalISOString returns formated date', function (done) {
-				assert.equal(column._toLocalISOString(new Date('2016-08-27')), '2016-08-27T03:00:00.000');
-				assert.equal(column._toLocalISOString(new Date('2015-01-03')), '2015-01-03T02:00:00.000');
-				assert.equal(column._toLocalISOString(new Date('2021-12-31')), '2021-12-31T02:00:00.000');
+				[
+					'2016-08-27',
+					'2015-01-03',
+					'2021-12-31'
+				].forEach(value => {
+					const date = column.toValue(value);
+					assert.equal(
+						column._toLocalISOString(date),
+						column.toValue(date.getTime() - date.getTimezoneOffset() * 6e4).toISOString().slice(0, 23)
+					);
+				});
+
 				done();
 			});
 
 			test('changing filter updates _filterInput', function (done) {
+				const min = column.toValue('2015-03-18'),
+					max = column.toValue('2023-03-21');
+
 				assert.isNull(column.filter.min);
 				assert.isNull(column.filter.max);
 
-				column.filter = {
-					min: new Date('2015-03-18'),
-					max: new Date('2023-03-21')
-				};
-
-				assert.equal(column._filterInput.min, '2015-03-18', 'Expect _filterInput.min to be local ISO String');
-				assert.equal(column._filterInput.max, '2023-03-21', 'Expect _filterInput.max to be local ISO String');
+				column.filter = {min, max};
+				const {max: fMax, min: fMin} = column._filterInput;
+				assert.equal(fMin, column._toLocalISOString(min).slice(0, 10), 'Expect _filterInput.min to be local ISO String');
+				assert.equal(fMax, column._toLocalISOString(max).slice(0, 10), 'Expect _filterInput.max to be local ISO String');
 
-				assert.equal(new Date(column._filterInput.min).getTime(), column.filter.min.getTime(), 'Expect min input and filter to be equal as dates');
-				assert.equal(new Date(column._filterInput.max).getTime(), column.filter.max.getTime(), 'Expect max input and filter to be equal as dates');
+				assert.equal(column.toValue(fMin).getTime(), min.getTime(), 'Expect min input and filter to be equal as dates');
+				assert.equal(column.toValue(fMax).getTime(), max.getTime(), 'Expect max input and filter to be equal as dates');
 
 				done();
 			});
@@ -153,7 +182,7 @@
 				assert.isNull(column._filterInput.min);
 				assert.isNull(column._filterInput.max);
 
-				column.addEventListener('filter-changed', function () {
+				onFilter(column, () => {
 					assert.equal(column.filter.min.getTime(), new Date('2015-03-18T00:00:00').getTime());
 					assert.equal(column.filter.max.getTime(), new Date('2023-03-21T23:59:59').getTime(), 'Expecting max date included');
 					done();
@@ -165,42 +194,47 @@
 			});
 
 			test('changing only _filterInput min updates filter min', function (done) {
-				column.addEventListener('filter-changed', function () {
+				onFilter(column, () => {
 					assert.equal(column.filter.min.getTime(), new Date('2015-08-27T00:00:00').getTime());
 					done();
 				});
 				column.set('_filterInput.min', '2015-08-27');
 			});
 
-			test('filtering on specific date with datetime source', function (done) {
-				// date: '2017-12-22T23:00:00Z'
+			test('filtering on specific date with datetime source', done => {
+				const value = data[5][column.valuePath], // '2017-12-22T23:00:00Z'
+					day = (new Date(value)).getDate();
 
-				assert.equal(column.getComparableValue(data[5], column.valuePath), new Date('2017-12-22T23:00:00Z').getTime());
-				column.addEventListener('filter-changed', function () {
-					assert.isTrue(column.getFilterFn()(data[5]));
+				onFilterItems(omnitable, column, items => {
+					assert.include(items.map(i => i[column.valuePath]), value);
 					done();
 				});
+				column._filterInput = {
+					min: `2017-12-${day}`,
+					max: `2017-12-${day + 1}`
+				};
 				column._filterInput = {
 					min: '2017-12-22',
 					max: '2017-12-23'
 				};
 			});
 
-			test('filtering on specific date with datetime source same day test', function (done) {
-				// date: '2017-12-22T23:00:00Z'
+			test('filtering on specific date, with datetime source, same day test', done => {
+				const value = data[5][column.valuePath], // '2017-12-22T23:00:00Z'
+					day = (new Date(value)).getDate();
 
-				column.addEventListener('filter-changed', function () {
-					assert.isTrue(column.getFilterFn()(data[5]));
+				onFilterItems(omnitable, column, items => {
+					assert.include(items.map(i => i[column.valuePath]), value);
 					done();
 				});
 				column._filterInput = {
-					min: '2017-12-23',
-					max: '2017-12-23'
+					min: `2017-12-${day}`,
+					max: `2017-12-${day}`
 				};
 			});
 		});
 
-		suite('datetime', function () {
+		suite('datetime' + domType, () => {
 			let omnitable,
 				column;
 
@@ -243,37 +277,44 @@
 			// });
 
 			test('_toInputString converts datetime to local string', function (done) {
-				assert.equal(column._toInputString(new Date(86400000)), '1970-01-02T02:00:00');
-				assert.equal(column._toInputString(new Date('2006-07-14T07:05:39')), '2006-07-14T07:05:39');
-				assert.equal(column._toInputString(new Date('2021-12-03T09:26:04')), '2021-12-03T09:26:04');
-				assert.equal(column._toInputString(new Date('2114-04-22T04:09:00')), '2114-04-22T04:09:00');
+				[
+					86400000,
+					'2006-07-14T07:05:39',
+					'2021-12-03T09:26:04',
+					'2114-04-22T04:09:00'
+				].forEach(value =>
+					assert.equal(column._toInputString(value), column._toLocalISOString(column.toValue(value)).slice(0, 19))
+				);
 				done();
 			});
 
-			test('_toHashString converts datetime to UTC string replacing : with .', function (done) {
-				assert.equal(column._toHashString(new Date(86400000)), '1970-01-02T00.00.00');
-				assert.equal(column._toHashString(new Date('2021-12-03T11:26:04')), '2021-12-03T09.26.04');
-				assert.equal(column._toHashString(new Date('2016-04-22T07:09:00')), '2016-04-22T04.09.00');
-				assert.equal(column._toHashString(new Date('2017-01-16T09:19:38')), '2017-01-16T07.19.38');
+			test('_toHashString converts datetime to UTC string replacing : with .', done => {
+				[
+					'2021-12-03T11:26:04',
+					'2016-04-22T07:09:00',
+					'2017-01-16T09:19:38'
+				].forEach(date =>
+					assert.equal(column._toHashString(date), column.toValue(date).toISOString().substr(0, 19).replace(/:/g, '.'))
+				);
 				done();
 			});
 
-			test('changing filter updates _filterInput', function (done) {
+			test('changing filter updates _filterInput', done => {
 				assert.isNull(column.filter.min);
 				assert.isNull(column.filter.max);
 				column.filter = {
-					min: new Date(86400000),
-					max: new Date(99, 5, 24, 11, 33, 30, 0)
+					min: new Date('1970-01-02T02:00:00'),
+					max: new Date('1999-06-24T11:33:30')
 				};
 				assert.equal(column._filterInput.min, '1970-01-02T02:00:00');
 				assert.equal(column._filterInput.max, '1999-06-24T11:33:30');
 				done();
 			});
 
-			test('changing _filterInput updates filter', function (done) {
-				column.addEventListener('filter-changed', function () {
-					assert.equal(column.filter.min.getTime(), 86400000);
-					assert.equal(column.filter.max.getTime(), new Date(99, 5, 24, 11, 33, 30, 0).getTime());
+			test('changing _filterInput updates filter', done => {
+				onFilter(column, () => {
+					assert.equal(column.filter.min.getTime(), new Date('1970-01-02T02:00:00').getTime());
+					assert.equal(column.filter.max.getTime(), new Date('1999-06-24T11:33:30').getTime());
 					done();
 				});
 				column._filterInput = {
@@ -283,7 +324,7 @@
 			});
 
 			test('changing only _filterInput min updates filter min', function (done) {
-				column.addEventListener('filter-changed', function () {
+				onFilter(column, () => {
 					assert.equal(column.filter.min.getTime(), new Date('2014-06-24T11:33:30').getTime());
 					done();
 				});
@@ -291,7 +332,7 @@
 			});
 		});
 
-		suite('time', function () {
+		suite('time' + domType, () => {
 			let omnitable,
 				column;
 
@@ -330,20 +371,20 @@
 			});
 
 			test('time toDate accepts limit as timestamp', function (done) {
-				assert.equal(column.toDate(new Date(Date.UTC(2029, 0, 2, 17, 23, 12)).getTime(), 86400000, Math.min).getTime(), 86400000);
+				assert.equal(column.toDate(new Date(2029, 0, 2, 17, 23, 12).getTime(), 86400000, Math.min).getTime(), 86400000);
 				done();
 			});
 
-			test('time getComparableValue returns right value', function (done) {
-				assert.equal(column.getComparableValue(data[2], 'time'), 0, 'Expected to parse time from miliseconds timestamp as number');
-				assert.equal(column.getComparableValue(data[4], 'time'), 56096000);
+			test('time getComparableValue returns right value', done => {
+				assert.equal(column.getComparableValue({time: '2015-03-18T00:00:00Z'}, 'time'), 0);
 				done();
 			});
 
-			test('time _toInputString returns local ISO string', function (done) {
+			test('time _toInputString returns local ISO string', done => {
 				assert.equal(column._toInputString(), null);
-				assert.equal(column._toInputString(new Date(86400000)), '02:00:00');
-				assert.equal(column._toInputString('2016-08-27T14:34:56Z'), '17:34:56');
+				assert.equal(column._toInputString('2019-11-03T17:21:44'), '17:21:44');
+				assert.equal(column._toInputString('2016-08-27T14:34:56'), '14:34:56');
+				assert.equal(column._toInputString('2016-08-27T14:34:56Z'), column._toLocalISOString(column.toValue('2016-08-27T14:34:56Z')).slice(11, 19));
 				done();
 			});
 
@@ -357,39 +398,41 @@
 				done();
 			});
 
-			test('changing filter updates _filterInput', function (done) {
+			test('changing filter updates _filterInput', done => {
 				assert.isNull(column.filter.min);
 				assert.isNull(column.filter.max);
 				column.filter = {
-					min: new Date(86400000),
-					max: '2016-08-27T14:34:56Z'
+					min: '2000-01-01T09:12:00',
+					max: '2016-08-27T09:34:56'
 				};
-				assert.equal(column._filterInput.min, '02:00:00');
-				assert.equal(column._filterInput.max, '17:34:56');
+				assert.equal(column._filterInput.min, '09:12:00');
+				assert.equal(column._filterInput.max, '09:34:56');
 				done();
 			});
 
-			test('changing _filterInput updates filter', function (done) {
+			test('changing _filterInput updates filter', done => {
 				assert.isNull(column._filterInput.min);
 				assert.isNull(column._filterInput.max);
 
-				column.addEventListener('filter-changed', function () {
-					assert.equal(column.filter.min.getTime(), new Date(Date.UTC(1970, 0, 1, 2, 30)).getTime());
-					assert.equal(column.filter.max.getTime(), new Date(Date.UTC(1970, 0, 1, 15, 34, 56)).getTime());
+				const min = '08:12:00',
+					max = '11:34:56';
+				onFilter(column, () => {
+					const {min: fMin, max: fMax} = column.filter;
+					assert.equal(fMin.getTime(), column.toValue(min).getTime());
+					assert.equal(fMax.getTime(), column.toValue(max).getTime());
 					done();
 				});
-				column._filterInput = {
-					min: '04:30:00',
-					max: '17:34:56'
-				};
+
+				column._filterInput = {min, max};
 			});
 
-			test('changing only _filterInput min updates filter min', function (done) {
-				column.addEventListener('filter-changed', function () {
-					assert.equal(column.filter.min.getTime(), new Date(Date.UTC(1970, 0, 1, 2, 21, 10)).getTime());
+			test('changing only _filterInput min updates filter min', done => {
+				const min = '04:21:10';
+				onFilter(column, () => {
+					assert.equal(column.filter.min.getTime(), column.toValue(min).getTime());
 					done();
 				});
-				column.set('_filterInput.min', '04:21:10');
+				column.set('_filterInput.min', min);
 			});
 
 		});
diff --git a/test/range.html b/test/range.html
index eba1aaef..626768b3 100644
--- a/test/range.html
+++ b/test/range.html
@@ -8,10 +8,10 @@
 	<script src="../../webcomponentsjs/webcomponents-lite.js"></script>
 	<script src="../../web-component-tester/browser.js"></script>
 	<script src="../../test-fixture/test-fixture-mocha.js"></script>
+	<script src="./helpers/utils.js"></script>
 
 	<link rel="import" href="../../test-fixture/test-fixture.html">
 	<link rel="import" href="../../iron-test-helpers/iron-test-helpers.html">
-	<link rel="import" href="helpers.html">
 	<link rel="import" href="../cosmoz-omnitable.html">
 	<link rel="import" href="../cosmoz-omnitable-columns.html">
 	<link rel="import" href="../demo/table-demo-behavior.html">
@@ -46,43 +46,44 @@
 	</test-fixture>
 
 	<script>
-	/*global sinon chai flush setupOmnitableFixture*/
 	(function () {
 		'use strict';
-		const data = [
-			{
-				age: 17,
-				amount: { amount: '12.4', currency: 'USD' },
-			},
-			{
-				amount: { amount: 2 }
-			},
-			{
-				age: -11,
-				amount: { amount: 678, currency: 'AUD' }
-			},
-			{
-				age: 9,
-				amount: { amount: -8, currency: 'EUR' }
-			},
-			{
-				age: 5,
-				amount: { amount: '3450', currency: 'DKK' }
-			},
-			{
-				amount: { amount: 2015, currency: 'EUR' }
-			},
-			{
-				amount: { amount: 347, currency: 'USD' }
-			},
-			{
-				amount: { amount: 2581, currency: 'EUR' }
-			}
-		];
+
+		const domType = getDomType(),
+			data = [
+				{
+					age: 17,
+					amount: { amount: '12.4', currency: 'USD' },
+				},
+				{
+					amount: { amount: 2 }
+				},
+				{
+					age: -11,
+					amount: { amount: 678, currency: 'AUD' }
+				},
+				{
+					age: 9,
+					amount: { amount: -8, currency: 'EUR' }
+				},
+				{
+					age: 5,
+					amount: { amount: '3450', currency: 'DKK' }
+				},
+				{
+					amount: { amount: 2015, currency: 'EUR' }
+				},
+				{
+					amount: { amount: 347, currency: 'USD' }
+				},
+				{
+					amount: { amount: 2581, currency: 'EUR' }
+				}
+			];
 
 		sinon.assert.expose(chai.assert, { prefix: '' });
 
-		suite('number', function () {
+		suite('number' + domType, () => {
 			let omnitable,
 				column;
 
@@ -188,7 +189,7 @@
 			});
 		});
 
-		suite('amount', function () {
+		suite('amount', () => {
 			let omnitable,
 				column;
 
@@ -339,7 +340,7 @@
 
 		});
 
-		suite('currency rates', function () {
+		suite('currency rates', () => {
 			let omnitable,
 				column;
 
@@ -448,12 +449,12 @@
 			});
 		});
 
-		suite('default currency', function () {
+		suite('default currency' + domType, () => {
 			let omnitable,
 				column;
 
 			setup(function (done) {
-				omnitable = setupOmnitableFixture('currency', data, o => {
+				omnitable = setupOmnitableFixture('currency', data, omnitable => {
 					column = omnitable.columns[0];
 					column.rates = {'EUR': 1, 'USD': 0.8169982616, 'AUD': 0.6529827192, 'SEK': 0.1019271438, 'GBP': 1.1347079368};
 					done();
diff --git a/test/xlsx-export.html b/test/xlsx-export.html
index 84e4613a..68b5eef2 100644
--- a/test/xlsx-export.html
+++ b/test/xlsx-export.html
@@ -8,10 +8,10 @@
 	<script src="../../webcomponentsjs/webcomponents-lite.js"></script>
 	<script src="../../web-component-tester/browser.js"></script>
 	<script src="../../test-fixture/test-fixture-mocha.js"></script>
+	<script src="./helpers/utils.js"></script>
 
 	<link rel="import" href="../../test-fixture/test-fixture.html">
 	<link rel="import" href="../../iron-test-helpers/iron-test-helpers.html">
-	<link rel="import" href="helpers.html">
 	<link rel="import" href="../cosmoz-omnitable.html">
 	<link rel="import" href="../cosmoz-omnitable-columns.html">
 	<link rel="import" href="../demo/table-demo-behavior.html">
@@ -49,31 +49,29 @@
 	</test-fixture>
 
 	<script>
-	/*global sinon chai flush setupOmnitableFixture*/
 	(function () {
 		'use strict';
 
+		const domType = getDomType();
 		sinon.assert.expose(chai.assert, { prefix: '' });
 
-		suite('xlsx-export-omnitable', function () {
-			var omnitable,
-				data = [
-					{ id: 0, 'first-name': 'Carl', amount: 12.4, date: new Date(2017, 7 - 1, 10) },
-					{ id: 1, 'first-name': 'Mia', amount: 678, date: new Date() },
-					{ id: 2, 'first-name': 'Selena', amount: 2300, date: new Date(Date.UTC(2017, 11, 1, 3, 23, 16))},
-					{ id: 3, 'first-name': 'Teo', amount: 7000, date: new Date(Date.UTC(2016, 0, 13, 10, 41, 58))},
-					{ id: 4, 'first-name': 'Klark', amount: 23019, date: new Date(Date.UTC(2029, 7, 30, 1, 27, 13)) },
-					{ id: 5, 'first-name': 'Lenotika', amount: 9304, date: new Date(Date.UTC(2013, 9, 13, 5, 7, 29)) },
-					{ id: 6, 'first-name': 'Manil', amount: 28420, date: new Date(Date.UTC(2018, 10, 3, 24, 1, 14)) }
-				];
-
-			setup(function (done) {
+		suite('xlsx-export-omnitable' + domType, () => {
+			let omnitable;
+			const data = [
+				{ id: 0, 'first-name': 'Carl', amount: 12.4, date: new Date(2017, 7 - 1, 10) },
+				{ id: 1, 'first-name': 'Mia', amount: 678, date: new Date() },
+				{ id: 2, 'first-name': 'Selena', amount: 2300, date: new Date(Date.UTC(2017, 11, 1, 3, 23, 16))},
+				{ id: 3, 'first-name': 'Teo', amount: 7000, date: new Date(Date.UTC(2016, 0, 13, 10, 41, 58))},
+				{ id: 4, 'first-name': 'Klark', amount: 23019, date: new Date(Date.UTC(2029, 7, 30, 1, 27, 13)) },
+				{ id: 5, 'first-name': 'Lenotika', amount: 9304, date: new Date(Date.UTC(2013, 9, 13, 5, 7, 29)) },
+				{ id: 6, 'first-name': 'Manil', amount: 28420, date: new Date(Date.UTC(2018, 10, 3, 24, 1, 14)) }
+			];
+
+			setup(done => {
 				omnitable = fixture('xlsx-export-fixture');
 				omnitable.data = data;
 
-				flush(function () {
-					Polymer.Base.async(done, 90);
-				});
+				flush(() => Polymer.Base.async(done, 90));
 			});
 
 			test('it instantiates a cosmoz-omnitable element', function (done) {
@@ -82,7 +80,7 @@
 			});
 
 			test('it is loading the name of first id column', function (done) {
-				var id = omnitable.querySelector('#id');
+				const id = omnitable.querySelector('#id');
 				assert.isDefined(id);
 				assert.equal(id.getString(), 'id');
 				done();
@@ -93,7 +91,7 @@
 				omnitable.selectItem(data[0]);
 				omnitable.selectItem(data[1]);
 				// prepare selected items, verify data
-				var xlsx = omnitable._prepareXlsxData(),
+				const xlsx = omnitable._prepareXlsxData(),
 					headers = xlsx[0];
 				assert.equal(headers[0], omnitable.columns[0].title);
 				assert.equal(headers.length, omnitable.columns.length);
@@ -101,9 +99,9 @@
 			});
 
 			test('is exporting as xlsx file', function (done) {
-				var spyXlsx = sinon.spy(omnitable, '_saveAsXlsxAction'),
-					stubSaveAs = sinon.stub(window, 'saveAs'),
-					args;
+				const spyXlsx = sinon.spy(omnitable, '_saveAsXlsxAction'),
+					stubSaveAs = sinon.stub(window, 'saveAs');
+
 				omnitable.selectItem(data[0]);
 				omnitable.selectItem(data[1]);
 
@@ -112,7 +110,7 @@
 				assert.calledOnce(spyXlsx);
 				assert.calledOnce(stubSaveAs);
 
-				args =  stubSaveAs.lastCall.args[0];
+				const args =  stubSaveAs.lastCall.args[0];
 				// verify params of SaveAs; name and type of file to be created
 
 				assert.equal(args.name, 'Test.xlsx');
@@ -124,9 +122,9 @@
 			});
 
 			test('click twice creates two files', function (done) {
-				let spyXlsx = sinon.spy(omnitable, '_saveAsXlsxAction'),
-					stubSaveAs = sinon.stub(window, 'saveAs'),
-					args;
+				const spyXlsx = sinon.spy(omnitable, '_saveAsXlsxAction'),
+					stubSaveAs = sinon.stub(window, 'saveAs');
+
 				for (let i = 0; i < data.length; i++) {
 					omnitable.selectItem(data[i]);
 				}
@@ -137,7 +135,7 @@
 				assert.calledTwice(spyXlsx);
 				assert.calledTwice(stubSaveAs);
 
-				args =  stubSaveAs.lastCall.args[0];
+				const args =  stubSaveAs.lastCall.args[0];
 
 				assert.equal(args.name, 'Test.xlsx');
 				assert.equal(args.type, 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet');
@@ -148,80 +146,77 @@
 			});
 		});
 
-		suite('toXlsx range tests', function () {
-			var omnitable,
+		suite('toXlsx range tests' + domType, () => {
+			let omnitable,
 				xlsx;
 			const data = [
-					{ number: 432,
-						amount: { currency: 'GBP', amount: 2781 },
-						date: new Date(Date.UTC(2020, 2, 14)),
-						time: new Date(Date.UTC(2020, 2, 14, 11, 48, 13)),
-						datetime: new Date(Date.UTC(2020, 2, 14, 11, 48, 13))
-					},
-					{ number: 7001,
-						amount: { currency: 'EUR', amount: 845 },
-						date: new Date(2029, 7, 30),
-						time: new Date(Date.UTC(2029, 7, 30, 1, 27, 13)),
-						datetime: new Date(Date.UTC(2029, 7, 30, 1, 27, 13))
-					},
-					{ number: 2405,
-						amount: { currency: 'USD', amount: 107 },
-						date: new Date(Date.UTC(2018, 4, 25, 2, 31, 29)),
-						time: new Date(Date.UTC(2018, 4, 25, 2, 31, 29)),
-						datetime: new Date(Date.UTC(2018, 4, 25, 2, 31, 29))
-					},
-					{ number: 108,
-						amount: { currency: 'BRL', amount: 4406 },
-						date: new Date(Date.UTC(2017, 0, 2, 7, 25, 11)),
-						time: new Date(Date.UTC(2017, 0, 2, 7, 25, 11)),
-						datetime: new Date(Date.UTC(2017, 0, 2, 7, 25, 11))
-					},
-					{ number: 857,
-						amount: { currency: 'RON', amount: 341 },
-						date: new Date(Date.UTC(2016, 1, 27, 17, 30, 51)),
-						time: new Date(Date.UTC(2016, 1, 27, 17, 30, 51)),
-						datetime: new Date(Date.UTC(2016, 1, 27, 17, 30, 51))
-					},
-					{ number: 73,
-						amount: { currency: 'DKK', amount: 11 },
-						date: new Date(Date.UTC(2013, 9, 13, 5, 7, 29)),
-						time: new Date(Date.UTC(2013, 9, 13, 5, 7, 29)),
-						datetime: new Date(Date.UTC(2013, 9, 13, 5, 7, 29))
-					},
-					{ number: 5774,
-						amount: { currency: 'EUR', amount: 932 },
-						date: '2024-03-14T13:05:07',
-						time: '2024-03-14T13:05:07',
-						datetime: '2024-03-14T13:05:07'
-					},
-					{ number: 0,
-						amount: { currency: 'AED', amount: 765432 },
-						date: 'Thu Mar 7 2009 06:25:52 GMT+0200 (EET)', // Bucharest, Romania
-						time: 'Thu Mar 7 2009 06:25:52 GMT+0200 (EET)',
-						datetime: 'Thu Mar 7 2009 06:25:52 GMT+0200 (EET)'
-					},
-					{ number: 59,
-						amount: { currency: 'AUD', amount: -101 },
-						date: '2012-10-12T07:22:46Z',
-						time: '2012-10-12T07:22:46Z',
-						datetime: '2012-10-12T07:22:46Z'
-					},
-					{ number: -340,
-						amount: { currency: 'CAD', amount: -4321 },
-						date: 'Tue Jan 16 2018 05:47:40 UTC -8', // Vancouver Canada
-						time: 'Tue Jan 16 2018 05:47:40 UTC -8',
-						datetime: 'Tue Jan 16 2018 05:47:40 UTC -8'
-					},
-					{ number: -22,
-						amount: { currency: 'EUR', amount: -22 },
-						date: 'Tue Jan 16 2018 14:06:29 UTC +1', // Lisbon, Portugal (Lisboa)
-						time: 'Tue Jan 16 2018 14:06:29 UTC +1',
-						datetime: 'Tue Jan 16 2018 14:06:29 UTC +1'
-					},
-				],
-				getRandomInt = function (min, max) {
-					return Math.floor(Math.random() * (max - min + 1)) + min;
-				};
+				{ number: 432,
+					amount: { currency: 'GBP', amount: 2781 },
+					date: new Date(Date.UTC(2020, 2, 14, 11, 48, 13)),
+					time: new Date(Date.UTC(2020, 2, 14, 11, 48, 13)),
+					datetime: new Date(Date.UTC(2020, 2, 14, 11, 48, 13))
+				},
+				{ number: 7001,
+					amount: { currency: 'EUR', amount: 845 },
+					date: new Date(Date.UTC(2029, 7, 30, 1, 27, 13)),
+					time: new Date(Date.UTC(2029, 7, 30, 1, 27, 13)),
+					datetime: new Date(Date.UTC(2029, 7, 30, 1, 27, 13))
+				},
+				{ number: 2405,
+					amount: { currency: 'USD', amount: 107 },
+					date: new Date(Date.UTC(2018, 4, 25, 2, 31, 29)),
+					time: new Date(Date.UTC(2018, 4, 25, 2, 31, 29)),
+					datetime: new Date(Date.UTC(2018, 4, 25, 2, 31, 29))
+				},
+				{ number: 108,
+					amount: { currency: 'BRL', amount: 4406 },
+					date: new Date(Date.UTC(2017, 0, 2, 7, 25, 11)),
+					time: new Date(Date.UTC(2017, 0, 2, 7, 25, 11)),
+					datetime: new Date(Date.UTC(2017, 0, 2, 7, 25, 11))
+				},
+				{ number: 857,
+					amount: { currency: 'RON', amount: 341 },
+					date: new Date(Date.UTC(2016, 1, 27, 17, 30, 51)),
+					time: new Date(Date.UTC(2016, 1, 27, 17, 30, 51)),
+					datetime: new Date(Date.UTC(2016, 1, 27, 17, 30, 51))
+				},
+				{ number: 73,
+					amount: { currency: 'DKK', amount: 11 },
+					date: new Date(Date.UTC(2013, 9, 13, 5, 7, 29)),
+					time: new Date(Date.UTC(2013, 9, 13, 5, 7, 29)),
+					datetime: new Date(Date.UTC(2013, 9, 13, 5, 7, 29))
+				},
+				{ number: 5774,
+					amount: { currency: 'EUR', amount: 932 },
+					date: '2024-03-14T13:05:07',
+					time: '2024-03-14T13:05:07',
+					datetime: '2024-03-14T13:05:07'
+				},
+				{ number: 0,
+					amount: { currency: 'AED', amount: 765432 },
+					date: 'Thu Mar 7 2009 06:25:52 GMT+0200 (EET)', // Bucharest, Romania
+					time: 'Thu Mar 7 2009 06:25:52 GMT+0200 (EET)',
+					datetime: 'Thu Mar 7 2009 06:25:52 GMT+0200 (EET)'
+				},
+				{ number: 59,
+					amount: { currency: 'AUD', amount: -101 },
+					date: '2012-10-12T07:22:46Z',
+					time: '2012-10-12T07:22:46Z',
+					datetime: '2012-10-12T07:22:46Z'
+				},
+				{ number: -340,
+					amount: { currency: 'CAD', amount: -4321 },
+					date: 'Tue Jan 16 2018 05:47:40 UTC -8', // Vancouver Canada
+					time: 'Tue Jan 16 2018 05:47:40 UTC -8',
+					datetime: 'Tue Jan 16 2018 05:47:40 UTC -8'
+				},
+				{ number: -22,
+					amount: { currency: 'EUR', amount: -22 },
+					date: 'Tue Jan 16 2018 14:06:29 UTC +1', // Lisbon, Portugal (Lisboa)
+					time: 'Tue Jan 16 2018 14:06:29 UTC +1',
+					datetime: 'Tue Jan 16 2018 14:06:29 UTC +1'
+				},
+			];
 
 			setup(function (done) {
 				omnitable = fixture('toXlsx-range-fixture');
@@ -240,13 +235,13 @@
 				});
 			});
 
-			test('prepares number values', function (done) {
-				const numbers = xlsx.map(row => row[0]),
-					values = ['numbers', 432, 7001, 2405, 108, 857, 73, 5774, 0, 59, -340, -22];
-
-				for (let i = 1; i <= data.length; i++) {
-					assert.equal(numbers[i], values[i]);
-				}
+			test('prepares number values', done => {
+				xlsx
+					.map(row => row[0])
+					.slice(1)
+					.forEach((value, index) => {
+						assert.equal(value, data[index].number);
+					});
 				done();
 			});
 
@@ -268,53 +263,41 @@
 			});
 
 			test('prepares date values', function (done) {
-				const dates = xlsx.map(row => row[2]);
-
-				assert.equal(new Date(dates[1]).getTime(), new Date(2020, 2, 14).getTime());
-				assert.equal(new Date(dates[2]).getTime(), new Date(2029, 7, 30).getTime());
-				assert.equal(new Date(dates[3]).getTime(), new Date(2018, 4, 25).getTime());
-				assert.equal(new Date(dates[4]).getTime(), new Date(2017, 0, 2).getTime());
-				assert.equal(new Date(dates[5]).getTime(), new Date(2016, 1, 27).getTime());
-				assert.equal(new Date(dates[6]).getTime(), new Date(2013, 9, 13).getTime());
-				assert.equal(new Date(dates[7]).getTime(), new Date(2024, 2, 14).getTime());
-				assert.equal(new Date(dates[8]).getTime(), new Date(2009, 2, 7).getTime());
-				assert.equal(new Date(dates[9]).getTime(), new Date(2012, 9, 12).getTime());
-				assert.equal(new Date(dates[10]).getTime(), new Date(2018, 0, 16).getTime());
-				assert.equal(new Date(dates[11]).getTime(), new Date(2018, 0, 16).getTime());
+				const column = omnitable.columns[2];
+				xlsx
+					.map(row => row[2])
+					.slice(1)
+					.forEach((value, index) => {
+						const date	= column.toValue(data[index].date);
+						date.setHours(0, 0, 0);
+						assert.equal(column.toValue(value).getTime(), date.getTime());
+					});
 				done();
 			});
 
 			test('prepares time values', function (done) {
-				const times = xlsx.map(row => row[3]);
-
-				assert.equal(times[1], '1:48:13 PM'); // +2h
-				assert.equal(times[2], '4:27:13 AM'); // +3h Daylight Saving Time
-				assert.equal(times[3], '5:31:29 AM'); // +3h
-				assert.equal(times[4], '9:25:11 AM'); // +2h
-				assert.equal(times[5], '7:30:51 PM'); // +2h
-				assert.equal(times[6], '8:07:29 AM'); // +3h
-				assert.equal(times[7], '1:05:07 PM'); // +2h
-				assert.equal(times[8], '6:25:52 AM'); // +2h
-				assert.equal(times[9], '10:22:46 AM'); // +3h
-				assert.equal(times[10], '3:47:40 PM'); // -8h
-				assert.equal(times[11], '3:06:29 PM'); // +1h
+				const column = omnitable.columns[3];
+				xlsx
+					.map(row => row[3])
+					.slice(1)
+					.forEach((value, index) => {
+						const time = column.toXlsxValue(data[index]);
+						assert.equal(value, time);
+					});
 				done();
+
 			});
 
 			test('prepares datetime values', function (done) {
-				const datetimes = xlsx.map(row => row[4]);
-
-				assert.equal(new Date(datetimes[1]).getTime(), new Date(Date.UTC(2020, 2, 14, 11, 48, 13)).getTime());
-				assert.equal(new Date(datetimes[2]).getTime(), new Date(Date.UTC(2029, 7, 30, 1, 27, 13)).getTime());
-				assert.equal(new Date(datetimes[3]).getTime(), new Date(Date.UTC(2018, 4, 25, 2, 31, 29)).getTime());
-				assert.equal(new Date(datetimes[4]).getTime(), new Date(Date.UTC(2017, 0, 2, 7, 25, 11)).getTime());
-				assert.equal(new Date(datetimes[5]).getTime(), new Date(Date.UTC(2016, 1, 27, 17, 30, 51)).getTime());
-				assert.equal(new Date(datetimes[6]).getTime(), new Date(Date.UTC(2013, 9, 13, 5, 7, 29)).getTime());
-				assert.equal(new Date(datetimes[7]).getTime(), new Date(Date.UTC(2024, 2, 14, 11, 5, 7)).getTime());
-				assert.equal(new Date(datetimes[8]).getTime(), new Date(Date.UTC(2009, 2, 7, 4, 25, 52)).getTime());
-				assert.equal(new Date(datetimes[9]).getTime(), new Date(Date.UTC(2012, 9, 12, 7, 22, 46)).getTime());
-				assert.equal(new Date(datetimes[10]).getTime(), new Date(Date.UTC(2018, 0, 16, 13, 47, 40)).getTime());
-				assert.equal(new Date(datetimes[11]).getTime(), new Date(Date.UTC(2018, 0, 16, 13, 6, 29)).getTime());
+				const column = omnitable.columns[4];
+				xlsx
+					.map(row => row[4])
+					.slice(1)
+					.forEach((value, index) => {
+						const time = column.toXlsxValue(data[index]);
+						assert.equal(value, time);
+						assert.equal(column.toValue(value).getTime(), column.toValue(data[index].datetime).getTime());
+					});
 				done();
 			});