TEMP-AIR®

TL;DR / Quick Answer: 

Temporary climate control on industrial and healthcare jobsites must strictly adhere to three core pillars of compliance to prevent catastrophic equipment failure and legal liability:

• Electrical Safety: All units must meet the new UL 60335-2-40 standard, which replaces the obsolete UL 1995.
• Worker Protection: Systems must satisfy OSHA’s General Duty Clause to proactively mitigate worker heat stress.
• Environmental Integrity: Healthcare and triage applications must comply with ASHRAE 170 for infection control and proper air exchange.

What You Should Know About New Electrical Safety Standards for Portable HVAC

The new electrical safety standard for portable HVAC equipment is UL 60335-2-40, which went into effect on January 1, 2025, to replace the outdated UL 1995 standard. All temporary climate control units must carry a recognized testing laboratory mark, such as UL or ETL, to ensure compliance with stricter requirements for flammable refrigerants and mechanical hazards.

When deploying temporary climate control solutions, adhering to the National Electrical Code (NFPA 70) is absolutely non-negotiable. All temporary wiring and electrical connections must be properly grounded and bonded to prevent catastrophic arc flashes and electrical shocks. By ensuring your fleet or rental equipment is actively certified under the UL 60335-2-40 standard, you future-proof your compliance with the latest refrigerant safety protocols and minimize severe operational liabilities.

How to Prevent Worker Heat Stress (Without Violating OSHA Guidelines)

To prevent worker heat stress under OSHA’s General Duty Clause (Section 5(a)(1)), employers must provide a workplace free from recognized heat hazards by utilizing engineering controls like portable air conditioning. OSHA officially recommends maintaining indoor work environments between 68°F and 76°F, with relative humidity controlled between 20% and 60%.

Relying solely on administrative controls, such as extra water breaks, is no longer sufficient for rigorous industrial environments. Facilities must prioritize mechanical cooling to physically alter the climate. Additionally, the CDC and NIOSH mandate that cool, potable water (under 59°F) be readily accessible near the work area, and that new workers undergo a gradual 7 to 14-day acclimatization plan to safely adapt to high-heat conditions.

What You Should Know About ASHRAE 170 and Healthcare Climate Control

ASHRAE 170 is the strict ventilation standard for health care facilities that mandates specific Air Changes per Hour (ACH) and relative humidity levels to maintain vital infection control. Temporary healthcare structures, such as surge tents and triage units, must follow this standard to protect patients and ensure the reliability of sensitive medical equipment.

To effectively meet ASHRAE 170 requirements, temporary HVAC systems must be equipped with high-efficiency HEPA filtration to capture and safely manage airborne pathogens. Furthermore, these systems must precisely manage room pressurization—sustaining negative pressure for infectious isolation rooms, or positive pressure for protective clinical environments. Facilities must also verify that their temporary systems meet the rigorous minimum required ACH (often between 6 to 12+ depending on the space type) as defined by ASHRAE/ASHE Guideline 43-2025.

We Analyzed Industrial Spot Coolers vs. Consumer HVAC (And This Is What We Learned)

Industrial-grade spot coolers feature heavy-duty steel chassis, advanced UL 60335-2-40 certification, and high ambient operating limits of 110°F to 120°F+. In contrast, consumer HVAC units use plastic or light metal chassis, rely on obsolete UL 1995 standards, and typically max out at 90°F to 95°F.

If you are evaluating equipment for your facility, use this hardened industrial suitability checklist to ensure mission-critical safety:

• Certification: Consumer units rely on UL 1995 (Obsolete), while Industrial Units use UL 60335-2-40 (Current).
• Chassis Build: Consumer units use Plastic/Light Metal, while Industrial Units utilize Heavy-Duty Steel.
• High Ambient Limit: Consumer units max out at 90°F – 95°F, while Industrial Units can withstand 110°F – 120°F+.
• Filtration: Consumer units provide Standard Mesh, while Industrial Units deliver HEPA / Multi-Stage filtration.
• Static Pressure: Consumer units offer Low pressure (Internal only), while Industrial Units offer High pressure (Supports long ducting).

Secure Your Mission-Critical Infrastructure with TEMP-AIR® Equipment Sales

Don’t leave your facility’s safety and climate control to chance. Whether you need an immediate fail-safe for an emergency or a long-term solution to future-proof your operations, our experts are on standby to help you evaluate the best strategy for your specific needs.

Visit the TEMP-AIR® website today to explore our full range of portable cooling and heating solutions, or call 1-888-535-8841 to speak directly with a climate control specialist!

Frequently Asked Questions (FAQ)

Question: Why do temporary job sites require specialized HVAC safety standards? 

Answer: The primary safety concern for temporary jobsite climate control is the mandatory transition to the UL 60335-2-40 standard, which fully replaces the legacy UL 1995. This standard ensures that HVAC equipment is safe for use with new-generation refrigerants. For industrial and healthcare applications, strict compliance with OSHA’s General Duty Clause and ASHRAE 170 is mandatory to ensure both worker safety and clinical infection control.

Question: What is the deadline for the new UL 60335-2-40 electrical safety standard? 

Answer: The transition became effective on January 1, 2025. All portable HVAC equipment manufactured or deployed after this date should carry a recognized testing laboratory mark (like UL or ETL) certifying it under this new standard to ensure compliance with updated refrigerant safety and mechanical hazard protocols.

Question: How does portable cooling assist with OSHA compliance? 

Answer: Under OSHA’s General Duty Clause, employers are legally required to provide a workplace free from recognized hazards, including extreme heat. Mechanical cooling is a recognized “engineering control” that physically reduces the risk of heat stress, which OSHA prefers over “administrative controls” like simply increasing water breaks.

Question: What are the specific requirements for temporary healthcare HVAC units? 

Answer: According to ASHRAE 170, systems must provide specific Air Changes per Hour (ACH)—typically between 6 to 12+—and maintain precise room pressurization. Additionally, these units must be equipped with HEPA filtration to manage airborne pathogens and protect sensitive medical equipment.

Question: Why can’t I use a high-end consumer AC unit for my jobsite? 

Answer: Consumer units are typically built with plastic chassis and designed for ambient temperatures only up to 90°F. Industrial-grade spot coolers use heavy-duty steel and are rated for high-ambient environments (110°F–120°F+). Furthermore, consumer units rarely support the high static pressure needed for long ducting runs or the specialized filtration required by industrial safety codes.