Despite significant advances in welding helmets, face masks for sanding/grinding etc. Harness designs currently in use have remained ostensibly the same for decades.

These time honoured designs whilst being adequate, present various issues which our Clamshell design addresses.

The adjustable band and side pivots design, which is standard in many products has several problematic features, defined as follows.

1) Attempts to combine a respirator mask with the band and pivots design are hampered by the side pivots which prevent movement necessary to facilitate a facial seal when this type of design is utilised.

In an attempt to remedy this issue, slimline filters mounted on a respirator mask with an independent elastic harness, worn behind a welding helmet had varying degrees of success, but are uncomfortable requiring two independent types of harness to be worn together.

2) The adjustment knob at the rear of the harness creates further problems for a user when working in the supine position. e.g. whilst working on their back on the undercarriage of a vehicle or similar activity.

3) The equipment tends to slide sideways when working horizontally, often impeding vision, creating safety and workmanship issues

The pursuit of a design to remedy these shortcomings required a departure from both the adjustable band and pivots, and elastic stretch designs, which would be completely different.

We instead, created a design which focuses on anterior and dorsal movement capability, thus eliminating the pivots restriction.

By use of a sliding mechanism connecting a mask to a rear moulding which cradels the rear of the users head, we have created a novel, new design which revolutionises the head harness market, improving function and safety with the added features of comfort and ease of fitting.

The clamshell harness may be used in various PPE purposed mask designs, ranging from designs which require a respirator included, to designs which do not.

When a respirator is present, the design creates an interactive pressure configuration which is particularly effective, creating a snug fit to the user's head.

The resulting balance creates a more effective and comfortable fit for the user, lessening neck strain and enabling the user to work with added comfort in the supine position.

When working horizontally, sideways slippage is reduced significantly and ease of movement is improved, resulting in greater safety and improved operational utility.