I linked a site that has a catalogue of attacks going back to 1890................Page after page after page of reports.
I will share one of my favorites (favorite because it demonstrates my point. I saw interviews with her on TV, pictures of her surgery/stitches, and photo's of the deceased mountain lion ):
13 December, 1994. A 25-year-old water quality specialist, Susanne Groves, was attacked and mauled by a cougar on the Ute Mountain Ute Indian Reservation (near Cortez, Colorado). Standing in the shallows down river from the Grass River Bridge, she was taking water samples from the Mancos River. At about 10:30 a.m., (the RMN reported it was 1:30 p.m.) she heard something moving on the bank above. It was awhile before she looked up and saw a lion standing on top of the river's north bank. When they made eye contact, it came down the embankment toward her. Groves stayed in the water thinking the cat was just curious and would leave. As a precaution, perhaps, she began moving from her position nearer to the north bank back toward the south bank where her vehicle was parked.
Instead of leaving, the cat entered the foot deep water without hesitation. Groves now angled across the river toward the north bank, keeping her eyes fixed on the lions as it stared intently back. She yelled and threw water and ice chunks at it. Nothing seemed to deter the cougar which continued to parallel her path, always easing closer. The lion never showed its teeth, nor did it assume any threatening pose such as crouching. The pair went back and forth across the river several times. Then Groves slipped on some rocks and lost her balance. When she fell, the cougar reared up to attack. Groves stated she thought the animal was going for her neck but since she was falling, its jaws instead closed on the back of her head. She was (held) under water for perhaps 10 seconds. Then she must have broken free, as she jumped up from the water and began to run for the south bank.
Once at the bank, she may have slipped, as the next thing she remembered was being on her back and shoving her arm in front of her face in a defensive move. The lion bit down on her arm, but somehow Groves managed to get on top of the lion, her arm still in the animal's mouth. She no longer cared. She shoved her arm as far back in the cat's throat as she could, effectively pinning the animal down. She reached for the forceps (hemostats) dangling in reach from her fishing jacket and stabbed the lion in the eye. She reported her intent was to kill it by reaching the brain.
The lion only responded by growling and biting her arm even harder and by continuing its struggle to get out from under her. This battle continued about 5 minutes until the lion finally released her arm as Groves continued stabbing it. Groves continued to keep the animal pinned beneath her for another 5 minutes or so, as she did not want to give it the strength from gaining firm footing. The lion finally squirmed free, and Groves sprang to her feet to face her attacker. The lion just stood, still staring, so Groves lunged at it to test what the lion would do. It remained standing still, so Groves began backing downstream toward her truck again. About 20 yards away, the bank was less steep and she climbed it and then followed a cow path toward her truck.
Groves managed to get back to her truck and drive for help. Her injuries included five puncture wounds in her head and cuts and scratches on her arms and legs. She was treated at Southwest Memorial Hospital in Cortez and released the same day. Federal Animal Damage Control officers got permission from Ute tribal officals and then used dogs to quickly track and kill the lion. It appeared to be an old female, weighing only 63 pounds - about half the weight for a healthy adult female. Its teeth were worn, so it may have been unable to catch enough food.
Source: (Gary Gerhardt; Rocky Mountain News; 12/15/94) (Cougar Attacks - Encounters of the Worst Kind by Kathy Etling; The Lyons Press; Copyright 2001, Pages 135-136)
http://www.cougarinfo.org/attacks2.htm
People survive cougar attacks all the time. You will note, that many of the fatalities are children, and solo women. Many people have successfully fought off cougars in full attack with nothing but feet and fist, and rock.
I would recommend a fixed blade on the belt, if he is in the mountains, he can get away with a longer knife. I would pick a fighting bowie, if I had the option. Something long enough and heavy enough to chop and stab. 9 inch plus blade. (of course I have a few knives that would work). He might not be willing to carry something that big.
If he is willing to carry a larger fixed blade something like a Cold Steel Khukri would be sweet. They are on sale for $100 off. Basically $200 for a 12 inch knife with 01 steel. Large finger guard on the Plus model. Will stab clear through a large cat, enough oomph to remove entire limbs, or cleave the head.
http://www.ltspecpro.com/Product/39LGKI/GURKHA_KUKRI_PLUS.aspx (I believe Cold Steel is a supporting member here, so if not, I can remove the link).
(their warranty is limited, but I have owned a lot of their products, including a Trailmaster in laminated steel that held up well for a decade before I sold it).
Depending on your budget, Also look at a ESSE Jungelas (less expensive than some large choppers. Nice knife, super warranty and a 9 inch blade), Stuff from Swamp Rat and Scrap Yard and Busse will all be different in price, but all are excellent. (Busse are higher end, Swamp Rat middle and Scrap Yard the cost effective line all from the same Family company Busse plant. They all feature a super warranty, basically forever to any owner, original or not).
If he does not want a fixed blade, I would suggest a large folder like a Cold Steel Talwar XL with opening thumb plate. It will open as you are drawing from pocket. The Espada XL is basically a pocket sword, but it really would be comforting in the hand if you were thinking a cougar had it's eyes on you.
My first choice would be a gun in an appropriate caliber, but I see you don't have that option.
For people saying your husband won't survive, See the above link (or below) I will link about 10 years worth of attacks: You will note, most survive, and even those attacked from behind in the photo's have better odds of surviving than not. One photo of a dead cougar shows the knife the old man used to kill lit. A two hand opening buck lock back with a piddly 3 inch blade.
http://www.cougarinfo.org/attacks3.htm
It is great that you are thinking about it, and hey, knives are cool, even if there is no threat of cougars. Any knife would be better than his hands and harsh language. Bear spray has been mentioned too, and that would be a great idea. A full sized back pack would help.
