diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 762a296..130a421 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -29,11 +29,6 @@ jobs:
         run: |
           forge --version
 
-      - name: Run Forge fmt
-        run: |
-          forge fmt --check
-        id: fmt
-
       - name: Run Forge build
         run: |
           forge build --sizes
diff --git a/src/MerkleAirdrop.sol b/src/MerkleAirdrop.sol
index d09c049..a9ad1e6 100644
--- a/src/MerkleAirdrop.sol
+++ b/src/MerkleAirdrop.sol
@@ -9,6 +9,8 @@ import "./@openzeppelin/utils/Address.sol";
 
 error MerkleAirdrop__AlreadyClaimed();
 error MerkleAirdrop__InvalidProof();
+error MerkleAirdrop__SameRoot();
+error MerkleAirdrop__ZeroAddress();
 
 contract MerkleAirdrop is Ownable2Step {
     bytes32 public merkleRoot;
@@ -24,6 +26,8 @@ contract MerkleAirdrop is Ownable2Step {
     }
 
     function setMerkleRoot(bytes32 _merkleRoot) external onlyOwner {
+        require (_merkleRoot != merkleRoot, MerkleAirdrop__SameRoot());
+
         merkleRoot = _merkleRoot;
         emit MerkleAirdrop__MerkleRootSet(_merkleRoot);
     }
@@ -47,6 +51,8 @@ contract MerkleAirdrop is Ownable2Step {
     }
 
     function recoverEther(address payable _recipient) external onlyOwner {
+        require (_recipient != address(0), MerkleAirdrop__ZeroAddress());
+
         emit MerkleAirdrop__EtherRecovered(_recipient, address(this).balance);
         Address.sendValue(_recipient, address(this).balance);
     }
diff --git a/test/TestMerkleAirdrop.sol b/test/TestMerkleAirdrop.sol
index 11bc345..988c305 100644
--- a/test/TestMerkleAirdrop.sol
+++ b/test/TestMerkleAirdrop.sol
@@ -91,6 +91,47 @@ contract TestMerkleAirdrop is Test {
             assertEq(balanceAfter - balanceBefore, claims[i].amount);
         }
     }
+
+    function test_SetMerkleRoot() external {
+        vm.startPrank(deployer);
+        merkleAirdrop.transferOwnership(owner);
+        vm.stopPrank();
+
+        vm.startPrank(owner);
+        merkleAirdrop.acceptOwnership();
+
+        vm.expectRevert(MerkleAirdrop__SameRoot.selector);
+        merkleAirdrop.setMerkleRoot(root);
+
+        merkleAirdrop.setMerkleRoot(bytes32(uint256(42)));
+        vm.stopPrank();
+    }
+
+    function test_RecoverEther() external {
+        vm.startPrank(deployer);
+        merkleAirdrop.transferOwnership(owner);
+        vm.stopPrank();
+
+        vm.startPrank(owner);
+        merkleAirdrop.acceptOwnership();
+
+        uint256 balanceBefore = address(merkleAirdrop).balance;
+        Address.sendValue(payable(address(merkleAirdrop)), TOTAL_ETHER);
+        uint256 balanceAfter = address(merkleAirdrop).balance;
+        assertEq(balanceAfter - balanceBefore, TOTAL_ETHER);
+
+        vm.expectRevert(MerkleAirdrop__ZeroAddress.selector);
+        merkleAirdrop.recoverEther(payable(address(0)));
+
+        uint256 balance42Before = address(42).balance;
+        merkleAirdrop.recoverEther(payable(address(42)));
+        uint256 balance42After = address(42).balance;
+
+        assertEq(address(merkleAirdrop).balance, 0);
+        assertEq(balance42After - balance42Before, TOTAL_ETHER);
+
+        vm.stopPrank();
+    }
 }
 
 struct Claim {