FORENSICS DETECTORS FD-91 Gas Detectors User Manual

If using fresh air:
- Ensure area is free from target gas contamination.
- Stabilize detector for at least 2 minutes.
If using nitrogen:
- Connect nitrogen cylinder to the gas detector.

7.3 Span Calibration Procedure

Ensure zero calibration is successful.

Connect reference gas cylinder using a calibration cap.
Set flow rate to 0.5 LPM.

Expose gas analyzer to reference gas for 1 minute.
Verify stabilized gas value display.
Save span calibration point per detector instructions.

அடிக்கடி கேட்கப்படும் கேள்விகள் (FAQ)

Q: How often should I calibrate the gas detector?

A: Calibration frequency depends on usage, but it is generally
recommended to calibrate at least every 6 months or as per
உற்பத்தியாளர் வழிகாட்டுதல்கள்.

Q: Can I use gases other than the ones listed for
அளவுத்திருத்தம்?

A: It is recommended to use only the specified gases for
calibration to ensure accurate measurements and compliance with
தரநிலைகள்.

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முறை
Calibration of Gas Detectors
Document ID: SOP-CAL-001 Revision: 1.0 Effective Date: May 14, 2025
1. நோக்கம் மற்றும் நோக்கம்
1.1 நோக்கம்
This Standard Operating Procedure (SOP) describes the method for calibrating gas detectors to ensure accurate measurement of specific gas concentrations in accordance with ISO/IEC 17025:2017 requirements.
1.2 நோக்கம்
This procedure applies to the calibration of portable gas detectors used for the detection and measurement of gases in the below table. The calibration process involves both zero calibration using fresh air or nitrogen, and span calibration using NIST-traceable reference gases as listed in the below table.

Target Gas Name Acetylene
Oxygen Ethylene Chlorine Carbon Monoxide Carbon Dioxide Ethylene Oxide Methane Hydrogen Hydrogen Sulfide Formaldehyde Hydrogen Chloride Hydrogen Cyanide Nitrogen Ammonia Nitrous Oxide Nitrogen Dioxide Phosphine Sulfur Dioxide Isobutylene Argon Helium Nitric Oxide Ethanol

Chemical Symbol C2H2
O2 C2H4 Cl2 CO2 CO2 ETO CH4
H2 H2S CH2O HCl HCN N2 NH3 N2O NO2 PH3 SO2 C4H8 Ar He NO C2H6O

Gas Range 0 – 50 ppm 0% – 21% 0 – 80 ppm 0 – 10 ppm 0 – 5000 ppm 0 – 100 %vol 0 – 10 ppm 0 – 50 %LEL 0 – 5,000 ppm 0 – 100 ppm 0 – 10 ppm 0 – 10 ppm 0 – 20 ppm 0 – 100 %vol 0 – 50 ppm 0 – 200 ppm 0 – 200 ppm 0-10 ppm 0 – 10 ppm 0 – 50 ppm 0-100 %vol 0-100 %vol 0-1000 ppm 0-500 ppm

2 குறிப்புகள்

· ISO/IEC 17025:2017 – General requirements for the competence of testing and calibration laboratories
· Manufacturer’s operation manual for the specific gas detector model being calibrated · NIST – Certificates of Analysis for reference gases used in calibration

3. வரையறைகள்

· Zero Calibration: The process of setting the gas detector to read zero in an environment free of the target gas.
· Span Calibration: The process of calibrating the gas detector to a known concentration of the target gas.
· Reference Gas: A gas with a known concentration that is NIST-traceable and used as a standard for calibration.

· LPM: Liters Per Minute, a unit of flow rate. · ppm: Parts Per Million, a unit of concentration. · %vol: percentage of volume, a unit of concentration.
4. பொறுப்புகள்
4.1 Calibration Technician
· Perform calibrations according to this SOP · Document all calibration activities · Verify that all equipment is functioning properly · Report any anomalies or issues encountered during calibration
4.2 Quality Manager
· Ensure that this SOP is implemented correctly · Review calibration records · Approve any deviations from this SOP · Ensure traceability of reference standards
5. Equipment and Materials
5.1 உபகரணங்கள்
· Gas detector to be calibrated · Calibration cap (as required per gas detector model) · Flow regulator capable of delivering 0.5 LPM · Timer or stopwatch · Thermometer and humidity for recording environmental conditions
5.2 பொருட்கள்
· NIST-traceable reference gas cylinders with appropriate concentrations for the target gas · Zero air or nitrogen cylinder (if fresh air is not suitable for zero calibration) · Connecting tubing compatible with the calibration gas
6 சுற்றுச்சூழல் நிலைமைகள்
6.1 Required Conditions
· Temperature: 20°C ± 5°C (68°F ± 9°F) · Relative Humidity: 40% to 60%
6.2 ஆவணம்

Record the environmental conditions at the beginning and end of each calibration procedure. If conditions fall outside the specified ranges, document this as a deviation and assess the impact on calibration results.
7. Calibration Procedure
7.1 Pre-Calibration Checks
1. Verify that the gas detector is in good working condition with no physical damage. 2. Check battery level to ensure adequate power for calibration. 3. Inspect all calibration equipment, including tubing and all connections. 4. Verify that reference gas cylinders are within their validity period. 5. Record the serial number of the gas detector and the certificate numbers of reference
gases. 6. Record environmental conditions.
7.2 பூஜ்ஜிய அளவுத்திருத்த செயல்முறை
1. Power on the gas detector and allow 2 minutes for stabilization in fresh air. 2. If using fresh air for zero calibration: a. Ensure the calibration area is free from target gas
contamination. b. Allow the detector to stabilize in fresh air for at least 2 minutes. 3. If using nitrogen for zero calibration: a. Connect the nitrogen cylinder to the gas detector
using the appropriate calibration cap. b. Set the flow rate to 0.5 LPM. c. Allow nitrogen to flow for at least 2 minutes. 4. The gas detector reading may not read precisely 0 ppm. Depending on the model, it may display 0.0 or 0.00 ppm. Depending on the scale it may also read in %vol. 5. Save the zero calibration point to the detector per the gas detector model instructions. 6. Verify that the real-time display reading shows 0 ppm (or 0.0/0.00 ppm according to the detector’s display precision or scale %vol). 7. Record the pre- and post-calibration zero readings.
7.3 Span Calibration Procedure
1. Ensure that zero calibration has been completed successfully before proceeding. 2. Connect the reference gas cylinder to the gas detector using a calibration cap or
equivalent. 3. Set the flow rate to 0.5 LPM. 4. Expose the gas analyzer to the reference gas for 1 minute or until the reading has
stabilized. Document any deviation from the standard exposure time. 5. Verify that the displayed gas value has stabilized. 6. Save this span calibration point to the gas detector per instructions of the gas detector
model. 7. Record the following:
o Pre-calibration reading (before adjusting) o Span gas concentration from the Certificate of Analysis

o Post-calibration reading 8. Allow the detector to return to fresh air and verify that the reading returns to zero.
7.4 Multi-Sensor Gas Calibration
For gas detectors with more than one gas sensor that require calibration to more than one target gas:
1. Repeat the zero and span calibration procedure (Section 7.2 and 7.3) for each target gas. 2. A mixed reference gas can be used to expose a multi-sensor gas detector. Undertake zero
and span calibration simultaneously for each gas sensor within the multi-gas detector. 3. If a mixed reference gas is not available, treat each gas sensor separately and following
Section 7.2 and 7.3. 4. Document the calibration results for each sensor separately (but on the same gas detector
calibration certificate).
7.5 அளவுத்திருத்த சரிபார்ப்பு
1. After completing all calibration steps, verify the calibration by exposing the detector to the reference gas again.
2. Record the verification reading. 3. The reading should be within ±4% of the reference gas concentration. 4. If verification fails, repeat the calibration procedure.
8. Documentation and Records
8.1 தேவையான ஆவணங்கள்
For each calibration performed, record the following information:
1. Date and time of calibration 2. Calibration technician name 3. Gas detector information:
o Manufacturer and model o Serial number 4. Reference gas information: o Gas type and concentration o Cylinder number o Certificate number o Expiration date 5. Environmental conditions: o Temperature o Relative humidity 6. Calibration results: o Pre-calibration zero reading

o Post-calibration zero reading o Pre-calibration span reading o Reference gas concentration used o Post-calibration span reading 7. Any deviations from this SOP 8. Any observations or comments
8.2 Calibration Certificate
Upon successful completion of calibration, issue a calibration certificate that includes:
1. Title: “Certificate of Calibration” 2. Laboratory name and address 3. Unique identification of the certificate 4. Identification of the calibration method used 5. Description and identification of the gas detector 6. Date of calibration 7. Calibration results 8. Environmental conditions 9. Signature of the person authorizing the certificate 10. Statement that results relate only to the items calibrated 11. Statement on measurement uncertainty 12. Reference to the traceability of measurements to NIST standards
9. Uncertainty Analysis
Calculate and report the measurement uncertainty for each calibration according to the laboratory’s uncertainty estimation procedure. The uncertainty is calculated as 95% confidence of the final calibration reading with a K factor equaling to 2. Items considered includes:
1. Reference gas uncertainty (from Certificate of Analysis) 2. Environmental conditions 3. Equipment resolution 4. Repeatability 5. Detector Drift during Calibration 6. Effect of gas flow rate
10. தரக் கட்டுப்பாடு
10.1 வழக்கமான சோதனைகள்
1. Perform regular checks of reference gases using secondary standards. 2. Perform regular quality control checks on calibration equipment (as required).
10.2 Non-conforming Work

If any part of the calibration process does not conform to this SOP:

1. Document the non-conformance. 2. Evaluate the impact on calibration results. 3. Take corrective action as necessary. 4. Notify the customer if results are affected.

11. திருத்த வரலாறு

திருத்தம்

தேதி

1.0

மே 16, 2025

Description of Changes Initial Release

Approved By Quality Manager

12 ஒப்புதல்கள்
Role Author Technical Reviewer Quality Manager

Name Dr. Koz Galatsis Dr. Koz Galatsis Dr. Koz Galatsis

Signature Dr. Koz Galatsis Dr. Koz Galatsis Dr. Koz Galatsis

தேதி
08/25/2025 08/25/2025 08/25/2025

பின் இணைப்பு 1
Example Certificate of Calibration – for a Single Gas Detector.

Certificate of Calibration USA NIST Traceability Calibration

Test Conditions: Calibration Method ID:
Manufacturer: Reference Gas(s): Cylinder Lot Number:

Calibration Location:

777 Silver Spur Road, Suite #130

Rolling Hills Estates, CA, 90274, USA

Temperature: 70F ±1%, Humidity: 52% RH ±1%

SOP-CAL-001

சான்றிதழ் எண்:

4567

Forensics Detectors

Detector Model Number:

FD-90A-CO

Detector Serial Number:

245686867

304-403306989-1

Reference Gas Expiration:

04/05/2029

INSPECTION RESULTS

Visual Inspection? Detector Functionality?
Alarm Functionality?

Normal, no anomalies Normal, no anomalies Normal, no anomalies

பாஸ் பாஸ் பாஸ்

CALIBRATION TEST RESULTS

Gas Name Reference Gas Concentration
Expanded Uncertainty 5%
(k=2, 95% confidence level)
Pre Zero Calibration (As Found) Post Zero Calibration (As Left) Pre Span Calibration (As Found) Post Span Calibration (As Left) Other Comments: N/A

CO 200 ppm ±10 ppm
0 பிபிஎம் 0 பிபிஎம் 189 பிபிஎம் 200 பிபிஎம்

Calibration Technician Name and Signature:
Austin Jun

பாஸ்
பாஸ்
Date of Calibration: 05/23/2025 Certificate Issue Date: 05/23/2025 Next Cal Due Date: 05/23/2026

The calibration results reported in this certificate relate only to the specific instrument / reference gas identified herein and are valid only for the conditions under which the calibration was performed. The reported expanded uncertainty of measurement is stated as the standard uncertainty of measurement multiplied by the coverage factor k=2, which for a normal distribution corresponds to a coverage probability of approximately 95%. All measurements performed during this calibration are traceable to the International System of Units (SI) through the National Institute of Standards and Technology (NIST). This certificate shall not be reproduced except in full, without written approval from Forensics Detectors.

பின் இணைப்பு 2
Example Certificate of Calibration – for a Multi-Gas Detector with 4 gas sensors.

Certificate of Calibration USA NIST Traceability Calibration

Test Conditions: Calibration Method ID:
Manufacturer: Reference Gas(s): Cylinder Lot Number:

Calibration Location: Forensics Detectors,

777 Silver Spur Road, Suite #130

Rolling Hills Estates, CA, 90274, USA

Temperature: 70F ±1%, Humidity: 52% RH ±1%

SOP-CAL-001

சான்றிதழ் எண்:

4567

Forensics Detectors

மாதிரி எண்:

FD-4S

O2, CO, H2S, CH4

வரிசை எண்:

245686867

304-403306989-1

Reference Gas Expiration:

04/05/2029

INSPECTION RESULTS

Visual Inspection? Detector Functionality?
Alarm Functionality?

Normal, no anomalies Normal, no anomalies Normal, no anomalies

பாஸ் பாஸ் பாஸ்

CALIBRATION TEST RESULTS

CH4 50%LEL ±3 %LEL
0% LEL 0% LEL 40% LEL 50% LEL

Calibration Technician Name and Signature:

Mr. Austin Jun
Austin Jun

O2 20.9%vol ±1%vol
0.0% 0.0% 20.9% 20.9%

CO 200 ppm ±10 ppm
0 பிபிஎம் 0 பிபிஎம் 200 பிபிஎம் 200 பிபிஎம்

H2S 25 ppm ±1 ppm
0 பிபிஎம் 0 பிபிஎம் 25 பிபிஎம் 25 பிபிஎம்

பாஸ் பாஸ்

Date of Calibration: 05/23/2025 Certificate Issue Date: 05/23/2025 Next Cal Due Date: 05/23/2026

ஆவணங்கள் / ஆதாரங்கள்

FORENSICS DETECTORS FD-91 Gas Detectors [pdf] பயனர் கையேடு
FD-91 Gas Detectors, FD-91, Gas Detectors, Detectors

குறிப்புகள்

பயனர் கையேடு

FD-91 Gas Detectors

விவரக்குறிப்புகள்

தயாரிப்பு பயன்பாட்டிற்கான வழிமுறைகள்

1. நோக்கம் மற்றும் நோக்கம்

2 குறிப்புகள்

3. வரையறைகள்

4. பொறுப்புகள்

5. Equipment and Materials

6 சுற்றுச்சூழல் நிலைமைகள்

7. Calibration Procedure

7.1 Pre-Calibration Checks

7.2 பூஜ்ஜிய அளவுத்திருத்த செயல்முறை

7.3 Span Calibration Procedure

அடிக்கடி கேட்கப்படும் கேள்விகள் (FAQ)

Q: How often should I calibrate the gas detector?

Q: Can I use gases other than the ones listed for அளவுத்திருத்தம்?

ஆவணங்கள் / ஆதாரங்கள்

குறிப்புகள்

கருத்து தெரிவிக்கவும்

பதிலை ரத்துசெய்

Q: Can I use gases other than the ones listed for
அளவுத்திருத்தம்?