Why Does USP <800> Require An N95 Mask?

USP <800> provides guidelines that “describes requirements including responsibilities of personnel handling hazardous drugs; facility and engineering controls; procedures for deactivating, decontaminating and cleaning; spill control; and documentation.” These standards are applicable to anyone in healthcare who is responsible for receiving, preparing, administering, or transporting hazardous drugs.

This guideline follows the National Institute for Occupational Safety and Health’s (NIOSH) definition of hazardous drugs. NIOSH defines a hazardous drug as one that exhibits carcinogenicity, teratogenicity, reproductive toxicity, organ toxicity (at low doses), genotoxicity, or new drugs that mimic existing hazardous drugs. If any of these are present in either humans or animals, the drug can be found hazardous. 

Why Does USP <800> Require An N95 Face Mask?

The simple reason behind why USP <800> requires an N95 face mask is relatively simple: to protect you. Some of the drugs that fall into the hazardous category can be dangerous if inhaled and an N95 protects you from that.

How Does An N95 Face Mask Work?

An N95 face mask actually contains a respirator, but the mask portion is designed to fit snugly on your face. This respirator combined with the tight fit make it especially effective at filtering airborne particles. 

So let’s break down what “N95” actually means. The “N” is a Respirator Rating Letter Class, which stands for “Non-Oil”. This means that you can use the mask if no oil-based contaminants are present. You might have also seen R95 or P95 masks available. This means they are oil resistant for 8 hours or oil proof, respectively.

The “95” portion of N95 is a reference to the efficacy of the mask. This means the mask is 95% efficient at removing particles .3 microns and larger. This is a Centers for Disease Control and Prevention (CDC) requirement for N95s. If a mask is 100% effective, it is actually 99.97% effective, because there is always a margin of error.

What Should You Look For In An N95?

N95s are important for your protection: they prevent you from breathing in the smallest of particles. But like all things in this world, not all N95s are created equally. When considering which one is right for you, there are a number of factors to think about.


How an N95 fits is a critical component of its effectiveness. When you’re choosing an N95, you want to make sure you choose one designed to fit well. A good fit does not just mean stuck to your face, though. It means comfortable. You might be wearing this mask for hours at a time and you need to be comfortable. If you’re used to wearing N95s, you’ll be familiar with the bruises they can leave if the fit is uncomfortable. That’s a tight fit, but not a good one.


With the fit, the filter, the material, and the general fact that something is covering your mouth and nose, your breathing can be impacted. You want to choose an N95 face mask that is comfortable to breathe in.


N95 face masks are not meant to be worn forever. After several hours, the filter will wear out and it needs to be replaced. This is typical of all N95 masks. However, N95s that wear out earlier than expected are a nuisance. Moreover, though, N95s that tear or whose straps break are downright dangerous. If you are handling hazardous drugs or if you’re in the presence of dangerous particles, the last thing you want is to suddenly be exposed to breathing it in. This is amplified by the fact that your hands might be full in the moment, or handling the dangerous material, so you can’t immediately fix your mask. You want an N95 mask that is durable and reliable, not just for your comfort but for your safety.

Filter Quality

What is an N95 face mask without an effective filter? If the respirator (or filter) part of the mask is not high quality, you might as well be wearing a surgical mask. While those masks have their time and place, they do not offer the same protection and benefits of an N95, because of its filter. So when you’re considering N95s, make sure you closely look into the filter’s effectiveness.

Choosing The Ideal N95

So what does the ideal N95 face mask look like? We think it looks like the SHIELD-95-MEDI Surgical N95 Respirator. This revolutionary new face mask has earned the title of “Fit Test Champion” as it has consistently proven to effortlessly fit a wide variety of facial features. Not only does it effectively fit many faces, it fits comfortably. The innovative 3-panel design, soft nose foam, and patent-pending clear view bar come together to provide a both comfortable and effective fit. Meanwhile, the clear view bar increases your field of vision, so you can see what you’re looking at without craning your neck. 

Moreover, SHIELD-95 offers unparalleled breathability. The 3-panel design maximizes the filtration surface while making breathing effortless. You might even forget you are wearing it, but it won’t fall off. SHIELD-95 uses a patent-pending weld technology so the mask is usable for more than one duty cycle, including reinforced straps. They are 3 times stronger than any other N95 respirator currently available. 

Lastly, the SHIELD-95 has a 98.27% filtration rate for particles 0.3 microns and larger. This sets the standard for widely available N95 respirators.

So why does this face mask have so much to offer?

It was designed by LWS: the world’s clean air experts for 40 years. LWS took their years of experience in cleanrooms, both as clean air experts and professionals who have to wear N95s constantly, and developed this innovative design. And now, LWS’s work is available to you.

Learn more about the SHIELD-95-MEDI Surgical N95 Respirator. 

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