#log-reduction-calculator {
max-width: 500px;
margin: 20px auto;
padding: 15px;
background: #fff;
border-radius: 5px;
box-shadow: 0 1px 3px rgba(0,0,0,0.1);
font-family: -apple-system, BlinkMacSystemFont, ‘Arial’, sans-serif;
color: #333;
box-sizing: border-box;
}
h2 {
text-align: center;
margin: 0 0 15px;
font-size: 1.4rem;
line-height: 1.2;
color: #333;
}
p {
text-align: center;
color: #666;
font-size: 14px;
margin-bottom: 15px;
}
.form-group {
margin-bottom: 15px;
position: relative;
}
label {
display: block;
margin-bottom: 5px;
font-size: 0.9rem;
font-weight: 600;
}
input[type=”number”] {
width: 100%;
padding: 8px;
border: 1px solid #ddd;
border-radius: 3px;
font-size: 0.9rem;
box-sizing: border-box;
}
input:focus {
border-color: #0073aa;
outline: none;
}
.tooltip {
position: relative;
display: inline-block;
margin-left: 5px;
}
.tooltip .tooltip-text {
visibility: hidden;
width: 160px;
background: #333;
color: #fff;
text-align: center;
border-radius: 3px;
padding: 5px;
position: absolute;
z-index: 10;
bottom: 125%;
left: 50%;
transform: translateX(-50%);
opacity: 0;
transition: opacity 0.3s;
font-size: 0.75rem;
}
.tooltip:hover .tooltip-text {
visibility: visible;
opacity: 1;
}
.button-group {
display: flex;
gap: 10px;
justify-content: center;
margin-top: 15px;
}
button {
padding: 8px 16px;
border: none;
border-radius: 3px;
cursor: pointer;
font-size: 0.9rem;
background: #0073aa;
color: #fff;
}
button:hover {
background: #005177;
}
#reset-btn {
background: #6c757d;
}
#reset-btn:hover {
background: #5a6268;
}
#result {
margin-top: 15px;
padding: 10px;
border-radius: 3px;
font-size: 0.9rem;
line-height: 1.4;
min-height: 20px;
}
#result.success {
background: #e6f4ea;
border: 1px solid #28a745;
}
#result.error {
background: #f8d7da;
border: 1px solid #dc3545;
}
noscript {
display: block;
color: #dc3545;
text-align: center;
margin-top: 10px;
font-size: 0.9rem;
}
@media (max-width: 500px) {
#log-reduction-calculator {
margin: 10px;
padding: 10px;
}
h2 {
font-size: 1.2rem;
}
.button-group {
flex-direction: column;
}
button {
width: 100%;
}
}
Log Reduction: ${logReduction}
Percentage Reduction: ${percentReduction}% `; resultDiv.className = ‘success’; } catch (error) { resultDiv.innerHTML = `Error: ${error.message}`; resultDiv.className = ‘error’; } } function reset() { form.reset(); resultDiv.className = ”; resultDiv.innerHTML = ‘Enter initial and final CFU values, then click “Calculate”.’; initialCfuInput.focus(); } document.getElementById(‘calculate-btn’).addEventListener(‘click’, calculate); document.getElementById(‘reset-btn’).addEventListener(‘click’, reset); form.addEventListener(‘keypress’, function(e) { if (e.key === ‘Enter’ && e.target.tagName !== ‘BUTTON’) { e.preventDefault(); calculate(); } }); })();
Log Reduction Calculator
Calculate the log reduction and percentage reduction of microorganisms after treatment.
Enter initial and final CFU values, then click “Calculate”.
JavaScript is disabled. Please enable it to use the calculator.
(function() {
if (!document.getElementById(‘log-reduction-calculator’)) return;
const form = document.getElementById(‘calc-form’);
const initialCfuInput = document.getElementById(‘initial-cfu’);
const finalCfuInput = document.getElementById(‘final-cfu’);
const resultDiv = document.getElementById(‘result’);
function calculate() {
resultDiv.className = ”;
resultDiv.innerHTML = ”;
try {
const initialCfu = parseFloat(initialCfuInput.value);
const finalCfu = parseFloat(finalCfuInput.value);
if (isNaN(initialCfu) || initialCfu <= 0) throw new Error('Initial CFU must be a positive number.');
if (isNaN(finalCfu) || finalCfu initialCfu) throw new Error(‘Final CFU cannot be greater than initial CFU.’);
let logReduction, percentReduction;
if (finalCfu === 0) {
logReduction = ‘Infinite’;
percentReduction = 100;
} else {
logReduction = Math.log10(initialCfu / finalCfu).toFixed(2);
percentReduction = ((initialCfu – finalCfu) / initialCfu * 100).toFixed(2);
}
resultDiv.innerHTML = `
Results:Log Reduction: ${logReduction}
Percentage Reduction: ${percentReduction}% `; resultDiv.className = ‘success’; } catch (error) { resultDiv.innerHTML = `Error: ${error.message}`; resultDiv.className = ‘error’; } } function reset() { form.reset(); resultDiv.className = ”; resultDiv.innerHTML = ‘Enter initial and final CFU values, then click “Calculate”.’; initialCfuInput.focus(); } document.getElementById(‘calculate-btn’).addEventListener(‘click’, calculate); document.getElementById(‘reset-btn’).addEventListener(‘click’, reset); form.addEventListener(‘keypress’, function(e) { if (e.key === ‘Enter’ && e.target.tagName !== ‘BUTTON’) { e.preventDefault(); calculate(); } }); })();