The Sweat Resistance SPF Laboratory Test In Vivo is a clinical study designed to measure the Sun Protection Factor (SPF) and verify the durability of a sunscreen formulation after perspiration exposure. This test simulates real-life conditions such as exercise or high temperatures to confirm that the product maintains its UV protection during sweating.

Purpose of the Test

The purpose of this test is to evaluate whether a sunscreen retains its UV-blocking performance when exposed to perspiration. It supports product claims such as “sweat-resistant,” “long-lasting SPF protection,” and “ideal for sports or outdoor activities,” while ensuring compliance with ISO 24444:2019 and ISO 18861 standards.

How the Test Works

This In Vivo Apparatus Test is conducted on human volunteers in a controlled laboratory environment. Sunscreen is applied to specific skin areas, which are then exposed to a standardized UV source to determine the minimal erythema dose (MED). To simulate perspiration, test areas undergo controlled humidity and temperature conditions that induce sweating before the second UV exposure. The SPF value is calculated by comparing UV resistance before and after sweat exposure.

Testing Standards

• ISO 24444:2019 — In Vivo determination of Sun Protection Factor (SPF)
• ISO 18861 — In Vivo evaluation of resistance properties of sunscreen products

Applications in Cosmetic Testing

• Verification of “Sweat Resistant” labeling claims
• SPF validation for sunscreens intended for active or outdoor use
• Performance testing of sport and endurance skincare products
• Regulatory compliance with EU and international sunscreen standards
• Support for claims such as “durable under heat,” “ideal for athletes,” and “long-lasting SPF protection”

Test Procedure

1. The study is performed under controlled laboratory conditions following ISO 24444:2019 and ISO 18861 methodologies.
2. The sunscreen product is applied to defined skin areas on each volunteer.
3. Baseline SPF is determined by measuring UV-induced erythema on protected and unprotected skin.
4. Volunteers are exposed to controlled heat and humidity to simulate sweating conditions (using climatic chambers or physical activity models).
5. UV exposure is repeated post-perspiration to assess SPF retention and sweat resistance.

Results & Reporting

The final report includes:

• Study protocol and environmental simulation parameters
• SPF measurements before and after induced sweating
• Volunteer data and statistical analysis
• Interpretation of sweat resistance performance and SPF stability
• Compliance confirmation with ISO 24444:2019 and ISO 18861

Why This Test Matters

During sports, outdoor work, or hot weather, sweat can reduce sunscreen effectiveness. The Sweat Resistance SPF Laboratory Test In Vivo confirms that the product continues to provide reliable protection under such conditions. This validation enhances consumer confidence and ensures compliance with global labeling and safety requirements.

Sample Requirements

• Sample size: 300 mL of finished product
• Number of volunteers: typically 10–20, following ISO guidelines
• Product type: sunscreens, sport creams, daily SPF products, or body lotions with UV protection
• Storage: room temperature, away from direct sunlight unless otherwise specified

Test Parameters

• Protocol: ISO 24444:2019 + ISO 18861
• Duration: 40 days (including preparation, testing, and analysis)
• Measurement: SPF value before and after sweat exposure
• Simulation: induced perspiration under controlled temperature and humidity
• Sample quantity: 300 mL

Turnaround Time

Typical turnaround time is approximately 40 days, depending on scheduling, volunteer availability, and environmental simulation conditions.

Deliverables

• Comprehensive laboratory report in PDF format
• SPF and sweat resistance evaluation data
• Statistical summary of SPF retention after perspiration
• Certificate confirming “Sweat Resistant” claim validity

Compliance & Standards

The Sweat Resistance SPF Laboratory Test In Vivo is performed under Good Clinical Practice (GCP) and in accordance with ISO 24444:2019 and ISO 18861. All experiments are conducted by trained professionals using controlled environmental chambers to ensure scientific precision and reproducibility.

Related Tests

• Water Resistance SPF Laboratory Test In Vivo – Sun Protection Factor
• Very Water Resistance SPF Laboratory Test In Vivo – Sun Protection Factor
• In Vitro UVA Protection Test (ISO 24443:2021)
• Photostability & UV Filter Efficacy Test